From d8580157c50056a280dedee3e8bc931901bf8f5b Mon Sep 17 00:00:00 2001 From: Dylan Van Assche Date: Wed, 12 Feb 2025 08:52:06 +0100 Subject: [PATCH] spec: rerender HTML --- spec/dev.html | 2 +- spec/docs/20250212/index.html | 3591 +++++++++++++++++++++++++++++++++ spec/docs/index.html | 506 +++-- 3 files changed, 3823 insertions(+), 276 deletions(-) create mode 100644 spec/docs/20250212/index.html diff --git a/spec/dev.html b/spec/dev.html index a829533..9ff2c93 100644 --- a/spec/dev.html +++ b/spec/dev.html @@ -232,7 +232,7 @@ // formal title, define it here // subtitle : "White Paper", // if you wish the publication date to be other than the last modification, set this - publishDate: "2025-02-11", + publishDate: "2025-02-12", // if the specification's copyright date is a range of years, specify // the start date here: copyrightStart: "2021", diff --git a/spec/docs/20250212/index.html b/spec/docs/20250212/index.html new file mode 100644 index 0000000..e991efd --- /dev/null +++ b/spec/docs/20250212/index.html @@ -0,0 +1,3591 @@ + + + + + + +RML-IO + + + + + + + + + + + + + + + +
+ +

RML-IO

+

+ Draft Community Group Report + +

+
+ +
Latest published version:
+ https://www.w3.org/rml-io/ +
+
Latest editor's draft:
https://w3id.org/rml/io/spec
+ + + + +
Editor:
+ Dylan Van Assche + + + + (IDLab – Ghent University – imec) +
+
+ Former editor: +
+ Anastasia Dimou + + + + (KU Leuven) +
+ + +
This Version
+ https://w3id.org/rml/io/spec/%thisDate%/ +
Previous Version
+ https://w3id.org/rml/io/spec/%prevDate%/ +
Website
+ https://www.w3.org/community/kg-construct/ +
+
+ +

+ Copyright + © + 2021-2025 + + the Contributors to the RML-IO + Specification, published by the + Knowledge Graph Construction Community Group under the + W3C Community Contributor License Agreement (CLA). A human-readable + summary + is available. + +

+
+
+

Abstract

This document describes Logical Source and Logical Target +to access data sources and targets.

+

A Logical Source is a formal model and common representation +for describing access to data sources. +A Logical Target is +a formal model and a common representation +for specifying how a Knowledge Graph should be exported to a given target.

+

Logical Source and Logical Target reuses existing data access descriptions +and is therefore not limited to a specific set of targets or data sources. +The current document describes the Logical Source and Logical Target concepts +through definitions and examples.

+

The version of this document is DRAFT.

+
+ +

Status of This Document

+ This specification was published by the + Knowledge Graph Construction Community Group. It is not a W3C Standard nor is it + on the W3C Standards Track. + + Please note that under the + W3C Community Contributor License Agreement (CLA) + there is a limited opt-out and other conditions apply. + + Learn more about + W3C Community and Business Groups. +

+ +

1. Conformance

As well as sections marked as non-normative, all authoring guidelines, diagrams, examples, and notes in this specification are non-normative. Everything else in this specification is normative.

+ The key words MAY and MUST in this document + are to be interpreted as described in + BCP 14 + [RFC2119] [RFC8174] + when, and only when, they appear in all capitals, as shown here. +

+ +

2. Overview

This section is non-normative.

+

This document specifies Logical Source and Logical Target, +Logical Source is a description +for specifying how a data source should be accessed. +A Logical Source description is not limited to a specific Source +which allows to access any type of Source and provides a reference formulation +to refer to data inside the Source.

+

Logical Target is +a description for defining how a generated +RDF [RDF-Concepts] +knowledge graph must be exported. +A Logical Target description is not tailored towards a specific Target +which allows to export the generated RDF triples to any type of Target +and provides fine-grained control over where each RDF triple is exported to.

+

Logical Source and Logical Target leverage +the access descriptions of data access +such as DCAT [DCAT], SD [SD], etc.

+

In this document, examples assume +the following namespace prefix bindings unless otherwise stated:

+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
PrefixNamespace
rmlhttp://w3id.org/rml/
formatshttp://www.w3.org/ns/formats/
sdhttp://www.w3.org/ns/sparql-service-description#
dcathttp://www.w3.org/ns/dcat#
tdhttps://www.w3.org/2019/wot/td#
hctlhttps://www.w3.org/2019/wot/hypermedia#
htvhttp://www.w3.org/2011/http#
d2rqhttp://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#
wotsechttps://www.w3.org/2019/wot/security#
idsahttps://w3id.org/idsa/core/
+

The examples are contained in pink colored boxes:

+
# This box contains the example's Logical Source description.
+ +
# This box contains the example's Logical Target description.
+ + +

3. Logical Source vocabulary

The Logical Source vocabulary namespace is http://w3id.org/rml/ +and its prefix is rml.

+

The Logical Source vocabulary consists of 2 classes:

+
    +
  1. rml:LogicalSource describes how data of a source can be referenced.
    2. +
  2. rml:Source describes how a source can be accessed, it referenced from a rml:LogicalSource.
    3. +
+

3.1 Defining Logical Sources

A Logical Source is an abstract logical source +which specifies the access to a data source to be used as +input for a Triples Map.

+

An Logical Source (rml:LogicalSource) MUST adhere to the properties defined for the +abstract logical source.

+

Furthermore, an Logical Source MUST have:

+
    +
  • exactly one source (rml:source) property which specifies how a +data source is using a Source (rml:Source).
    • +
+

The reference formulation MUST be specified in +the case that the data source is a relational database, +CSV, TSV, XML, or JSON data sources.

+

By default rml:SQL2008Query for databases, +rml:CSV for CSV and TSV data sources. +XPath for XML and JSONPath for JSON and JSONL data sources.

+

By default, the iterator is considered a row, +if not specified:

+
    +
  • In the case of CSV or TSV data sources, the value of + rml:iterator is considered a "row" and must not be specified.
    • +
  • In the case of XML and JSON data sources, it is a valid reference + to an element or an object respectively considering the + reference formulation specified.
    • +
  • In the case of relational databases, the value of rml:iterator is either + a SQL query (rml:referenceFormulation rml:SQL2008Query) or the SQL table + name (rml:referenceFormulation rml:SQL2008Table). For SQL table names, + they can be converted to a SQL query using the following SQL query template: + SELECT * FROM {table} where {table} is the table name.
    • +
+

The Logical Source definition requires only the source (rml:source) +to be specified, all other properties are optional. +If a property is specified, it MUST only occur once.

+ + + + + + + + + + + + + +
PropertyDomainRange
rml:sourcerml:LogicalSourceIRI
+
+ Logical Source structure +
Figure 1 The structure of Logical Source
+
+ +

3.1.1 Reference formulations

+

Each Logical Source has a +reference formulation to define how +to express a reference to elements of the data of the input +data source. +Several reference formulation +(rml:ReferenceFormulation) are defined in this specification:

+
    +
  • rml:CSV: CSV or TSV data sources
    • +
  • rml:JSONPath: JSON documents
    • +
  • rml:XPath: XML documents with optionally +the definition of XML namespaces used in references. +By default, no namespaces are defined.
    • +
  • rml:SQL2008Query: SQL query for a relational database.
    • +
  • rml:SQL2008Table: Shortcut to select all columns from a SQL table.
    • +
+

rml:XPath may specify zero or more +rml:namespace properties with a rml:Namespace. +A rml:Namespace contains the following required properties:

+
    +
  • rml:namespacePrefix: A Literal with the prefix used for the XML namespace.
    • +
  • rml:namespaceURL: A Literal with the URL identifying the XML namespace.
    • +
+

These reference formulations are defined in the [RML-IO-Registry].

+
<#XMLNamespace> a rml:LogicalSource;
+     rml:source [ a rml:Source, rml:FilePath;
+         rml:path "/path/to/file/data.xml";
+     ];
+     rml:referenceFormulation [ a rml:XPathReferenceFormulation;
+       rml:namespace [ a rml:Namespace;
+         rml:namespacePrefix "ex";
+         rml:namespaceURL "http://example.org";
+       ];
+     ];
+     rml:iterator "/xpath/ex:namespace/expression";
+.
+ +

Since rml:source is open to any IRI, you can implement your own source access +description for data source that are not +covered by existing vocabularies such as paginated Web APIs which implement pagination +in a Web API specific way.

+

3.2 Source

+

A Source (rml:Source) defines how a +data source should be accessed. +It complements other source descriptions +such as SD Service, CSVW Table, DCAT Distribution, etc. +to support encoding, null values, compression, and other access properties. +The properties of a Source take precedence over the properties of other source +descriptions, for example: rml:encoding takes precedence over csvw:encoding +if both are specified.

+

A Source MUST have the following properties:

+
    +
  • zero or one rml:encoding property, which specifies the encoding +of the data inside the source. Defaults to rml:UTF-8 if not specified.
    • +
  • zero or more rml:null describes which data values inside the source +should be considered as NULL.
    +The value for this predicate defaults to the default NULL token +of the underlying data model (e.g., NULL in relational databases +and null in JSON) and are always processed as such. +Some data models have no such default NULL token, such as CSV. +When that is the case, then nothing is considered NULL unless specified by +rml:null.
    +Example: CSV does not have a default NULL character, +so no value is considered NULL. +However, JSON has a NULL character specified: null, +this one is used together with the ones specified through rml:null. +For a relational database, rml:null "foo" results into the following values +considered as NULL: {NULL, "foo"} where NULL comes from the relational +database model as NULL value.
    • +
  • zero or one rml:compression specifies if the source is compressed +and the used compression algorithm. Defaults to no compression.
    • +
+
<#JSON> a rml:LogicalSource;
+     rml:source [ a rml:Source, rml:FilePath;
+       rml:path "/path/to/data.json.gz";
+       rml:null ""; # empty string as NULL besides default null character
+       rml:compression rml:gzip; # GZip compression
+       rml:encoding rml:UTF-16; # UTF-16 encoding
+     ];
+     rml:referenceFormulation rml:JSONPath;
+     rml:iterator "$.jsonpath.expression";
+.
+ + + + + + + + + + + + + + + + + + + + + + + + +
PropertyDomainRange
rml:encodingrml:Sourcerml:Encoding
rml:nullrml:SourceLiteral
rml:compressionrml:Sourcerml:Compression
+

3.2.1 NULL values

+

Each Source MAY describe the values that should be considered as NULL +with rml:null, similar to NULL in relational databases. +By default, standardized NULL values are always considered, +but additional ones can be specified. Multiple NULL values are allowed. +For example, in relational databases NULL is always considered as a NULL +value while also an empty column can be considered as a NULL value by +specifying it through rml:null in a Source.

+

3.2.2 Compression formats

+

Each Source MAY specify the compression with rml:compression +to apply when exporting RDF triples to a Source for saving storage space. +Several compression formats are defined:

+
    +
  • rml:none: No compression is applied
    • +
  • rml:gzip: GZip compression
    • +
  • rml:zip: Zip archive with Zip compression
    • +
  • rml:tarxz: Tar archive with Xz compression
    • +
  • rml:targz: Tar archive with GZip compression
    • +
+

If unspecified, the default value is no compression. +This namespace is NOT limited to the listed compression formats +and MAY be extended in the future.

+

3.2.3 Encoding formats

+

Each Source MAY describe the encoding format to use when exporting +RDF triples to a Source. Several encoding formats are defined:

+
    +
  • rml:UTF-8: UTF-8 encoding
    • +
  • rml:UTF-16: UTF-16 encoding
    • +
+

If unspecified, the default value is rml:UTF-8. +This namespace is NOT limited to the listed compression formats +and may be extended in the future.

+

3.3 Examples

The following example shows a Source of a CSV file. +RML-IO-Registry provides also support for CSVW which allows more fine-grained control +over CSV files such as delimeters, encoding, etc. but it is not required for +Processors to implement CSVW, only CSV is the minimum to be compliant with +the RML IO module.

+
<#CSV> a rml:LogicalSource;
+     rml:source [ a rml:Source, rml:FilePath;
+        rml:path "/path/to/data.csv";
+        rml:null "NULL";
+        rml:null "";
+     ];
+     rml:referenceFormulation rml:CSV;
+.
+ +

Note that there is no rml:iterator present because its default is row. +This particular CSV file has two different ways to specify a NULL value: NULL +or an empty value. Implementations need to check if a value is equal to one of +the values defined by rml:null to check for NULL values in the data.

+

The following example shows a Source specified for a MySQL database querying +the student table. The database username and password are provided as well.

+
<#RDB> a rml:LogicalSource;
+    rml:source [ a rml:Source, d2rq:Database;
+        d2rq:jdbcDSN "jdbc:mysrml://localhost/example";
+        d2rq:jdbcDriver "com.mysql.jdbc.Driver";
+        d2rq:username "user";
+        d2rq:password "password";
+    ];
+    rml:iterator "SELECT * FROM student;";
+    rml:referenceFormulation rml:SQL2008Query;
+.
+ +

A shortcut is available to select all columns from a table, +such as in the example above, by using the rml:SQL2008Table +as rml:referenceFormulation.

+

Relative paths to files are covered by a source access description included +in this specification which subclasses rml:Source as rml:FilePath. +This access description allows accessing files relative from:

+
    +
  • rml:CurrentWorkingDirectory: relative to the current working directory of the RML processor.
    • +
  • rml:MappingDirectory: relative to the location of the RML mapping.
    • +
  • A string Literal: a string describing an absolute path against which relative paths are resolved, similar to the Base URI in RFC3986.
    • +
+

If rml:root is not specified, it defaults to rml:CurrentWorkingDirectory.

+ + + + + + + + + + + + + + + + + + +
PropertyDomainRange
rml:rootrml:FilePathrml:CurrentWorkingDirectory, rml:MappingDirectory or Literal
rml:pathrml:FilePathLiteral
+

Example of accessing a CSV file relative to the current working directory. +The file's absolute path is $CURRENT_WORKING_DIR/file.csv where $CURRENT_WORKING_DIR is +the location of the RML mapping.

+
<#RelativePathCWD> a rml:LogicalSource;
+  rml:source [ a rml:FilePath, rml:Source;
+    rml:root rml:CurrentWorkingDirectory;
+    rml:path "./file.csv";
+  ];
+.
+ +

Example of accessing a JSON file relative to the path of the mapping. +The file's absolute path is $MAPPING_DIR/file.json where $MAPPING_DIR is +the location of the RML mapping.

+
<#RelativePathMapping> a rml:LogicalSource;
+  rml:source [ a rml:FilePath, rml:Source;
+    rml:root rml:MappingDirectory;
+    rml:path "./file.json";
+  ];
+  rml:referenceFormulation rml:JSONPath;
+  rml:iterator "$";
+.
+ +

Example of accessing an XML file relative to an absolute root path +specified by a string Literal. The file's absolute path is /root/file.xml.

+
<#RelativePathLiteral> a rml:LogicalSource;
+  rml:source [ a rml:FilePath, rml:Source;
+    rml:root "/root";
+    rml:path "file.xml";
+  ];
+  rml:referenceFormulation rml:JSONPath;
+  rml:iterator "$";
+.
+ +

4. Logical Target vocabulary

The LogicalTarget vocabulary namespace is http://w3id.org/rml/ +and it's prefix is rml.

+

The LogicalTarget vocabulary consists of rml:LogicalTarget and rml:Target +classes to describe how a knowledge graph must be exported after generation.

+

4.1 Defining Logical Targets

A Logical Target is any target to where RDF triples are exported to.

+ + + + + + + + + + + + + +
PropertyDomainRange
rml:targetrml:LogicalTargetTarget
+
    +
  • The target access description (rml:target) MUST specify how to access +the target through an rml:Target. +The Target definition requires only the target (rml:target) to be specified, +all other properties are optional.
    • +
+

4.2 Target

+

A Target describes how a target must be accessed when exporting RDF triples. +An external vocabulary such as DCAT, SD, etc. is allowed here. +If a target cannot be accessed with existing vocabulary, a custom vocabulary +can be used, for example: handling an authentication flow may be specific +for that specific target. A custom ontology can be used here to describe +this authentication flow such as W3C Web of Things Security.

+

A Target (rml:Target) MAY contain the following properties:

+
    +
  • The serialization format (rml:serialization) MAY specify +the serialization format for exporting a knowledge graph. +The serialization format is described using the W3C +formats namespace. +By default, the serialization format is N-Quads [N-Quads].
    • +
  • The compression algorithm (rml:compression) MAY describe +the compression algorithm to apply when exporting a knowledge graph. +By default, no compression is applied.
    • +
  • The encoding (rml:encoding) MAY specify which encoding must be used +when exporting a knowledge graph. +By default, UTF-8 is used.
    • +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + +
PropertyDomainRange
rml:serializationrml:LogicalTargetformats:Format
rml:moderml:Targetrml:Mode
rml:compressionrml:Targetrml:Compression
rml:encodingrml:Targetrml:Encoding
+
+ Logical Target structure +
Figure 2 The structure of Logical Target
+
+ +

4.2.1 Serialization formats

+

Each Target MAY describe the serialization format +with rml:serialization to use when exporting RDF triples to a Target. +The possible formats are defined in the W3C +formats namespace +such as N-Quads, N-Triples, JSON-LD, Turtle, etc. +If unspecified, the default format is N-Quads [N-Quads].

+

4.2.2 Mode

+

Each Target MAY describe the operation mode when accessing a Target +with rml:mode to specify if the Target must be appended, overwritten, etc. +If not specified, defaults to rml:Write. +This property accepts the range of rml:Mode:

+
    +
  • rml:Read: read-only mode (r). Start beginning of file. Not useful for targets. File must exist.
    • +
  • rml:ReadWrite: read-write mode (r+). Start beginning of file, no truncation. Only write part is useful for targets. File must exist.
    • +
  • rml:Write: write mode (w). Truncate/create file and start at the beginning to add new data.
    • +
  • rml:WriteRead: write-read mode (w). Truncate/create file and start at the beginning to add new data. Only write part is useful for targets
    • +
  • rml:Append: append-only mode. Existing file is kept and new data is appended at the end. File is created if not exist.
    • +
  • rml:AppendRead: append-read mode. Existing file is kept and new data is appended at the end. File is created if not exist.
    • +
+

4.2.3 Compression formats

+

Each Target MAY specify the compression with rml:compression +to apply when exporting RDF triples to a Target for saving storage space. +Several compression formats are specified by the comp namespace:

+
    +
  • rml:none: No compression is applied
    • +
  • rml:gzip: GZip compression
    • +
  • rml:zip: Zip archive with Zip compression
    • +
  • rml:tarxz: Tar archive with Xz compression
    • +
  • rml:targz: Tar archive with GZip compression
    • +
+

If unspecified, the default value is no compression. +This namespace is NOT limited to the listed compression formats +and MAY be extended in the future.

+

4.2.4 Encoding formats

+

Each Target MAY describe the encoding format to use when exporting +RDF triples to a Target. Several encoding formats are defined:

+
    +
  • rml:UTF-8: UTF-8 encoding
    • +
  • rml:UTF-16: UTF-16 encoding
    • +
+

If unspecified, the default value is UTF-8. +This namespace is NOT limited to the listed compression formats +and MAY be extended in the future.

+

4.2.5 Relative paths

+

Relative paths to files are covered by a target access description included +in this specification which subclasses rml:Target as rml:FilePath re-used from the Logical Source.

+

4.3 Examples

The following example show a Target of an RDF dump in Turtle [Turtle] +format with GZip compression and UTF-8 encoding:

+
<#FileDump> a rml:LogicalTarget;
+    rml:target [ a rml:Target, rml:FilePath;
+        rml:path "/data/dump.ttl";
+        rml:compression rml:gzip;
+        rml:encoding rml:UTF-8;
+    ];
+    rml:serialization formats:Turtle;
+.
+ + +

5. Logical Source in RML

[RML-Core] introduces an abstract logical source +as an abstract construct to describe how a data source + can be accessed to be used in a Triples Map.

+

In this specification we introduce the Logical Source to describe how an input +data source can be accessed.

+

In the example below, a CSV file is transformed into a knowledge graph. +The CSV file is accessed using the [CSVW] vocabulary, +transformed into a knowledge graph using [RML] mappings,

+
id;name;nickname
+0;Nathan Ford;Mastermind
+1;Sophie Devereaux;Grifter
+2;Eliot Spender;Hitter
+3;Parker;Thief
+4;Alec Hardison;Hacker
+ +
<#CSVSourceAccess> a rml:Source, rml:FilePath;
+  rml:root rml:CurrentWorkingDirectory;
+  rml:path "./Leverage.csv";
+.
+ +
@base <http://example.com/ns#> .
+
+<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#CSVSourceAccess>;
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.com/{id}";
+    rml:class foaf:Person;
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname";
+    ];
+  ];
+.
+ +
<http://example.org/0> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://xmlns.com/foaf/0.1/Person> _b0 .
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Nathan Ford" _b0 .
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Mastermind" _b0 .
+<http://example.org/1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://xmlns.com/foaf/0.1/Person> _b0 .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Sophie Devereaux" _b0 .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Grifter" _b0 .
+<http://example.org/2> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://xmlns.com/foaf/0.1/Person> _b0 .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "Eliot Spencer" _b0 .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Hitter" _b0 .
+<http://example.org/3> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://xmlns.com/foaf/0.1/Person> _b0 .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Parker" _b0 .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Thief" _b0 .
+<http://example.org/4> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://xmlns.com/foaf/0.1/Person> _b0 .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/name> "Alec Hardison" _b0 .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/nickname> "Hacker" _b0 .
+ +

6. Logical Target in RML

RML is aligned with the Logical Target vocabulary +by extending rml:TermMap with the rml:logicalTarget property +to describe on Term Map [RML] level where each triple must be directed to. +A Term Map is a function that generates an RDF term +from a logical reference [RML]. +The result of that function is known as the term map's generated +RDF term [RDF-Concepts] +such as subjects, predicates, objects, named graphs and language tags.

+

Each RML processor has a default target where generated triples are exported. +Logical Targets provide a mechanism to override this default target for some +of the triples to be exported.

+

Logical Targets are defined in Term Maps. A Term Map MAY contain +one or more rml:logicalTarget properties to export all triples containing +the generated term to different targets. Specifically, when generating a +triple t, if any of the term maps involved in the generation of t +contains a Logical Target LT, then triple t exported to target LT. +If none of those Term Maps contains a Logical Target, +then the triple t is sent to the default target of the RML processor.

+

Multiple Logical Targets MAY be combined by specifying multiple Logical Targets +in the same Term Map or multiple Term Maps of the same RDF triple +(Section 8. Combining multiple Targets). +Logical Targets MAY be overriden by using a separate Triples Map +or conditions [FnO] (Section 9. Overriding Targets).

+

If the mapping document contains no Targets, +the processor falls back to the default target, +as it is specified through the processor's +specific configuration file or command line parameters. +If a mapping document contains at least one Target, +the processor will export the triples to these Targets, +triples which do not have one or more Target(s) assigned, +are exported to the default target of the processor.

+ + + + + + + + + + + + + +
PropertyDomainRange
rml:logicalTargetrml:TermMaprml:LogicalTarget
+

In the example below, a CSV file is transformed into a knowledge graph. +The CSV file is accessed using the [CSVW] vocabulary, +transformed into a knowledge graph using [RML] mappings, +and exported to two Logical Targets, which are accessed through the [DCAT] +vocabulary. +The knowledge graph is exported as N-Quads to the first Target, +and as Turtle to the second Target. +The Turtle file of the second Target is also compressed using the Zip +compression algorithm.

+
id;name;nickname
+0;Nathan Ford;Mastermind
+1;Sophie Devereaux;Grifter
+2;Eliot Spender;Hitter
+3;Parker;Thief
+4;Alec Hardison;Hacker
+ +
<#CSVSourceAccess> a rml:Source, rml:FilePath;
+  rml:root rml:CurrentWorkingDirectory;
+  rml:path "./Leverage.csv";
+.
+ +
@base <http://example.com/ns#> .
+
+<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#CSVSourceAccess>;
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.com/{id}";
+    rml:logicalTarget <#TargetDump1>;
+    rml:class foaf:Person;
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+      rml:logicalTarget <#TargetDump2>;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump2>;
+  rml:serialization formats:Turtle;
+.
+ +
<#Dump1> a rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+
+<#Dump2> a rml:FilePath;
+  rml:path "/data/dump2.ttl.zip";
+  rml:compression rml:zip;
+.
+ +
# file:///data/dump1.nq
+<http://example.org/0> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://xmlns.com/foaf/0.1/Person> _b0 .
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Nathan Ford" _b0 .
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Mastermind" _b0 .
+<http://example.org/1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://xmlns.com/foaf/0.1/Person> _b0 .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Sophie Devereaux" _b0 .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Grifter" _b0 .
+<http://example.org/2> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://xmlns.com/foaf/0.1/Person> _b0 .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "Eliot Spencer" _b0 .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Hitter" _b0 .
+<http://example.org/3> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://xmlns.com/foaf/0.1/Person> _b0 .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Parker" _b0 .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Thief" _b0 .
+<http://example.org/4> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://xmlns.com/foaf/0.1/Person> _b0 .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/name> "Alec Hardison" _b0 .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/nickname> "Hacker" _b0 .
+
+# file:///data/dump2.ttl.zip
+@prefix foaf: <http://xmlns.com/foaf/0.1/> .
+
+<http://example.org/0>
+  foaf:name "Nathan Ford";
+.
+<http://example.org/1>
+  foaf:name "Sophie Devereaux";
+.
+<http://example.org/2>
+  foaf:name "Eliot Spencer";
+.
+<http://example.org/3>
+  foaf:name "Parker";
+.
+<http://example.org/4>
+  foaf:name "Alec Hardison";
+.
+ + +

7. Single targets

In the following examples, the RDF triples are exported to a single Target. +In some examples, not all RDF triples have a dedicated Target assigned, +therefore, they will be exported to the default Target of the processor.

+

7.1 Subject Map

All triples containing the generated subject are exported +to the specified targets in the Subject Map [RML].

+

The following example exports all triples containing +the generated subject http://example.org/{id} +to an RDF dump with N-Quads as serialization format and GZip compression:

+
[
+  {
+    "id": 0,
+    "name": "Monica Geller",
+    "age": 33
+  },
+  {
+    "id": 1,
+    "name": "Rachel Green",
+    "age": 34
+  },
+  {
+    "id": 2,
+    "name": "Joey Tribbiani",
+    "age": 35
+  },
+  {
+    "id": 3,
+    "name": "Chandler Bing",
+    "age": 36
+  },
+  {
+    "id": 4,
+    "name": "Ross Geller",
+    "age": 37
+  }
+]
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Friends.json";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:JSONPath;
+    rml:iterator "$.[*]";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{id}";
+    rml:logicalTarget <#TargetDump1>;
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.name";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:age;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.age";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Quads;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nq.gz";
+  rml:compression rml:gzip;
+.
+ +
<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Monica Geller" .
+<http://example.org/0> <http://xmlns.com/foaf/0.1/age> "33" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Rachel Green" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/age> "34" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "Joey Tribbiani" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/age> "35" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Chandler Bing" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/age> "36" .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/name> "Ross Geller" .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/age> "37" .
+ +

7.2 Predicate Map

All triples containing the generated predicate are exported +to the specified targets in the Predicate Map [RML].

+

The following example exports all triples containing +the generated predicate foaf:name to an RDF dump +with Turtle as serialization format and Zip compression:

+
[
+  {
+    "id": 0,
+    "name": "Monica Geller",
+    "age": 33
+  },
+  {
+    "id": 1,
+    "name": "Rachel Green",
+    "age": 34
+  },
+  {
+    "id": 2,
+    "name": "Joey Tribbiani",
+    "age": 35
+  },
+  {
+    "id": 3,
+    "name": "Chandler Bing",
+    "age": 36
+  },
+  {
+    "id": 4,
+    "name": "Ross Geller",
+    "age": 37
+  }
+]
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Friends.json";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:JSONPath;
+    rml:iterator "$.[*]";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{id}";
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+      rml:logicalTarget <#TargetDump1>;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.name";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:age;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.age";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:Turtle;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.ttl.gz";
+  rml:compression rml:gzip;
+.
+ +
# file:///data/dump1.ttl.zip
+@prefix foaf: <http://xmlns.com/foaf/0.1/> .
+@base <http://example.com/ns#> .
+
+<http://example.org/0>
+  foaf:name "Monica Geller";
+.
+<http://example.org/1>
+  foaf:name "Rachel Green";
+.
+<http://example.org/2>
+  foaf:name "Joey Tribbiani";
+.
+<http://example.org/3>
+  foaf:name "Chandler Bing";
+.
+<http://example.org/4>
+  foaf:name "Ross Geller";
+.
+
+# default target of the processor
+<http://example.org/0> <http://xmlns.com/foaf/0.1/age> "33" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/age> "34" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/age> "35" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/age> "36" .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/age> "37" .
+ +

7.3 Object Map

All triples containing the generated object are exported +to the specified targets in the Object Map [RML].

+

The following example exports all triples containing +the generated object from the reference name to an RDF dump +with N-Triples as serialization format:

+
[
+  {
+    "id": 0,
+    "name": "Monica Geller",
+    "age": 33
+  },
+  {
+    "id": 1,
+    "name": "Rachel Green",
+    "age": 34
+  },
+  {
+    "id": 2,
+    "name": "Joey Tribbiani",
+    "age": 35
+  },
+  {
+    "id": 3,
+    "name": "Chandler Bing",
+    "age": 36
+  },
+  {
+    "id": 4,
+    "name": "Ross Geller",
+    "age": 37
+  }
+]
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Friends.json";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:JSONPath;
+    rml:iterator "$.[*]";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{id}";
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.name";
+      rml:logicalTarget <#TargetDump1>;
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:age;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.age";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+ +
# file:///data/dump1.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Monica Geller" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Rachel Green" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "Joey Tribbiani" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Chandler Bing" .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/name> "Ross Geller" .
+
+# default target of the processor
+<http://example.org/0> <http://xmlns.com/foaf/0.1/age> "33" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/age> "34" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/age> "35" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/age> "36" .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/age> "37" .
+ +

7.4 Graph Map

All triples within a named graph are exported to the specified targets +in the Graph Map [RML]. +The named graph influences to where the named graph's triples +may be exported to as the Target's serialization format must +support named graphs such as N-Quads, JSON-LD or TriG. +When a Target contains a serialization format +which does not support named graphs and a Graph Map is used, +the mapping is considered invalid. +If a named graph is spread over multiple targets, +all targets must be combined to access the complete named graph. +In case RDF triples are not within a specific named graph, +they are added to the default graph as specified +by the [R2RML] specification.

+

The following example exports all triples in the named graph ex:Friends +to an RDF dump with N-Quads as serialization format:

+
[
+  {
+    "id": 0,
+    "name": "Monica Geller",
+    "age": 33
+  },
+  {
+    "id": 1,
+    "name": "Rachel Green",
+    "age": 34
+  },
+  {
+    "id": 2,
+    "name": "Joey Tribbiani",
+    "age": 35
+  },
+  {
+    "id": 3,
+    "name": "Chandler Bing",
+    "age": 36
+  },
+  {
+    "id": 4,
+    "name": "Ross Geller",
+    "age": 37
+  }
+]
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Friends.json";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:JSONPath;
+    rml:iterator "$.[*]";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{id}";
+    rml:graphMap [
+      rml:logicalTarget <#TargetDump1>;
+      rml:constant ex:Friends;
+    ];
+   ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.name";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:age;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.age";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nq";
+.
+ +
# file:///data/dump1.nq
+<http://example.org/0> <http://xmlns.com/foaf/0.1/age> "33" <http://example.org/Friends> .
+<http://example.org/0> <http://xmlns.com/foaf/0.1/age> "33" <http://example.org/Friends> .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/age> "34" <http://example.org/Friends> .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/age> "34" <http://example.org/Friends> .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/age> "35" <http://example.org/Friends> .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/age> "35" <http://example.org/Friends> .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/age> "36" <http://example.org/Friends> .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/age> "36" <http://example.org/Friends> .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/age> "37" <http://example.org/Friends> .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/age> "37" <http://example.org/Friends> .
+ +

7.5 Language Map

All triples with a language tag are exported to the specified targets +in the Language Map [RML].

+

The following examples export all triples with a language tag +to a RDF dump with N-Triples as serialization format:

+
[
+  {
+    "id": 0,
+    "name": "Monica Geller",
+    "age": 33
+  },
+  {
+    "id": 1,
+    "name": "Rachel Green",
+    "age": 34
+  },
+  {
+    "id": 2,
+    "name": "Joey Tribbiani",
+    "age": 35
+  },
+  {
+    "id": 3,
+    "name": "Chandler Bing",
+    "age": 36
+  },
+  {
+    "id": 4,
+    "name": "Ross Geller",
+    "age": 37
+  }
+]
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Friends.json";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:JSONPath;
+    rml:iterator "$.[*]";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{id}";
+   ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.name";
+      rml:languageMap [
+        rml:logicalTarget <#TargetDump1>;
+        rml:constant "en";
+      ];
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:age;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.age";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+ +
# file:///data/dump1.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Monica Geller"@en .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Rachel Green"@en .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "Joey Tribbiani"@en .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Chandler Bing"@en .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/name> "Ross Geller"@en .
+
+# default target of the processor
+<http://example.org/0> <http://xmlns.com/foaf/0.1/age> "33" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/age> "34" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/age> "35" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/age> "36" .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/age> "37" .
+ +

7.6 Datatype Map

All triples with a datatype are exported to the specified targets +in the Datatype Map [RML].

+

The following examples export all triples with a datatype xsd:integer +to a RDF dump with N-Triples as serialization format:

+
[
+  {
+    "id": 0,
+    "name": "Monica Geller",
+    "age": 33
+  },
+  {
+    "id": 1,
+    "name": "Rachel Green",
+    "age": 34
+  },
+  {
+    "id": 2,
+    "name": "Joey Tribbiani",
+    "age": 35
+  },
+  {
+    "id": 3,
+    "name": "Chandler Bing",
+    "age": 36
+  },
+  {
+    "id": 4,
+    "name": "Ross Geller",
+    "age": 37
+  }
+]
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Friends.json";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:JSONPath;
+    rml:iterator "$.[*]";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{id}";
+   ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.name";
+      rml:languageMap [
+        rml:constant "en";
+      ];
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:age;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.age";
+      rml:datatypeMap [ a rml:DatatypeMap;
+        rml:constant xsd:integer;
+        rml:logicalTarget <#TargetDump1>;
+      ]
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+ +
# file:///data/dump1.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/age> "33"^^xsd:integer .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/age> "34"^^xsd:integer .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/age> "35"^^xsd:integer .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/age> "36"^^xsd:integer .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/age> "37"^^xsd:integer .
+
+# default target of the processor
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Monica Geller"@en .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Rachel Green"@en .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "Joey Tribbiani"@en .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Chandler Bing"@en .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/name> "Ross Geller"@en .
+ +

7.7 Function Map

[
+  {
+    "id": 0,
+    "name": "Monica Geller",
+    "age": 33
+  },
+  {
+    "id": 1,
+    "name": "Rachel Green",
+    "age": 34
+  },
+  {
+    "id": 2,
+    "name": "Joey Tribbiani",
+    "age": 35
+  },
+  {
+    "id": 3,
+    "name": "Chandler Bing",
+    "age": 36
+  },
+  {
+    "id": 4,
+    "name": "Ross Geller",
+    "age": 37
+  }
+]
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Friends.json";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:JSONPath;
+    rml:iterator "$.[*]";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{id}";
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:functionExecution <#Execution>;
+      rml:return grel:stringOut;
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:age;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "$.age";
+    ];
+  ];
+.
+
+<#Execution> a rml:FunctionExecution;
+  rml:logicalTarget <#TargetDump1>;
+  rml:function grel:toUppercase;
+  rml:input [ a rml:Input;
+    rml:parameter grel:valueParam;
+      rml:inputValueMap [
+        rml:reference "$.name"
+      ]
+  ]
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Quads;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nq.gz";
+  rml:compression rml:gzip;
+.
+ +
# dump1.nq.gz
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "MONICA GELLER" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "RACHEL GREEN" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "JOEY TRIBBIANI" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "CHANDLER BING" .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/name> "ROSS GELLER" .
+
+# default target of the processor
+<http://example.org/0> <http://xmlns.com/foaf/0.1/age> "33" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/age> "34" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/age> "35" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/age> "36" .
+<http://example.org/4> <http://xmlns.com/foaf/0.1/age> "37" .
+ +

8. Combining multiple Targets

Multiple Targets MAY be specified for the same triple +in the same or multiple Term Maps. +If multiple Targets are defined in the same Term Map, +all triples containing the generated Term are exported +to all the specified Targets. +In case multiple Term Maps of the same RDF triple contain more than one Target, +the generated triples are exported to all the specified Targets. +If multiple Term Maps of an RDF triple refer multiple times to the same Target, +the RDF triple is written only once to the target to avoid duplicates.

+

8.1 Multiple Targets in the same Term Map

All triples are exported to all Targets, if the Term Map contains multiple +Targets. In the example a Subject Map has three specified Targets, +all triples with the subject http://example.org/{@id} are exported +to the three specified Targets:

+
    +
  • Target 1: /data/dump.nt.zip, N-Triples serialization, Zip compression
    • +
  • Target 2: /data/dump.jsonld.tar.xz, JSON-LD serialization, TarXz compression
    • +
  • Target 3: /data/dump.rdf.tar.gzip, RDF/XML serialization, TarGZip compression
    • +
+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+    rml:logicalTarget <#TargetDump1>;
+    rml:logicalTarget <#TargetDump2>;
+    rml:logicalTarget <#TargetDump3>;
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump2>;
+  rml:serialization formats:JSON-LD;
+.
+<#TargetDump3> a rml:LogicalTarget;
+  rml:target <#Dump3>;
+  rml:serialization formats:RDF_XML;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt.zip";
+  rml:compression rml:zip;
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.jsonld.tar.xz";
+  rml:compression rml:tarxz;
+.
+<#Dump3> a rml:Target, rml:FilePath;
+  rml:path "/data/dump3.rdf.tar.gz";
+  rml:compression rml:targz;
+.
+ +
# file:///data/dump1.nt.zip
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" .
+
+# file:///data/dump2.jsonld.tar.xz
+[
+  {
+    "@id": "http://example.org/0",
+    "http://xmlns.com/foaf/0.1/name": [
+      {
+        "@value": "Kara Danvers"
+      }
+    ]
+  },
+  {
+    "@id": "http://example.org/1",
+    "http://xmlns.com/foaf/0.1/name": [
+      {
+        "@value": "Alex Danvers"
+      }
+    ]
+  },
+  {
+    "@id": "http://example.org/2",
+    "http://xmlns.com/foaf/0.1/name": [
+      {
+        "@value": "J'onn J'onzz"
+      }
+    ]
+  },
+  {
+    "@id": "http://example.org/3",
+    "http://xmlns.com/foaf/0.1/name": [
+      {
+        "@value": "Nia Nal"
+      }
+    ]
+  }
+]
+
+# file:///data/dump3.rdf.tar.gz
+<?xml version="1.0" encoding="utf-8" ?>
+<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+    xmlns:foaf="http://xmlns.com/foaf/0.1/">
+  <rdf:Description rdf:about="http://example.org/0">
+    <foaf:name>Kara Danvers</foaf:name>
+  </rdf:Description>
+  <rdf:Description rdf:about="http://example.org/1">
+    <foaf:name>Alex Danvers</foaf:name>
+  </rdf:Description>
+  <rdf:Description rdf:about="http://example.org/2">
+    <foaf:name>J'onn J'onzz</foaf:name>
+  </rdf:Description>
+  <rdf:Description rdf:about="http://example.org/3">
+    <foaf:name>Nia Nal</foaf:name>
+  </rdf:Description>
+</rdf:RDF>
+ +

8.2 Subject Map and Predicate Map

All triples containing the subject http://example.org/{id} +are exported to TargetDump1 +and all triples containing the predicate foaf:name +are exported to TargetDump2.

+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+    rml:logicalTarget <#TargetDump1>;
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+      rml:logicalTarget <#TargetDump2>;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname/text()";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" .
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Supergirl" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Sentinel" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Martian Manhunter" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Dreamer" .
+
+# file:///data/dump2.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" .
+ +

8.3 Subject Map and Object Map

All triples containing the subject http://example.org/{id} +are exported to TargetDump1 +and all triples containing the object reference name/text() +are exported to TargetDump2.

+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+    rml:logicalTarget <#TargetDump1>;
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+      rml:logicalTarget <#TargetDump2>;
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname/text()";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" .
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Supergirl" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Sentinel" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Martian Manhunter" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Dreamer" .
+
+# file:///data/dump2.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" .
+ +

8.4 Predicate Map and Object Map

All triples containing the predicate foaf:name +are exported to TargetDump1 +and all triples containing the object reference nickname/text() +are exported to TargetDump2.

+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+      rml:logicalTarget <#TargetDump1>;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname/text()";
+      rml:logicalTarget <#TargetDump2>;
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" .
+
+# file:///data/dump2.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Supergirl" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Sentinel" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "Martian Manhunter" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Dreamer" .
+ +

8.5 Subject Map, Predicate Map and Object Map

All triples containing the subject http://example.org/{@id} +are exported to TargetDump1 +and all triples containing the object reference nickname/text() or +predicate foaf:nickname are exported to TargetDump2.

+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+    rml:logicalTarget <#TargetDump1>;
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+      rml:logicalTarget <#TargetDump2>;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname/text()";
+      rml:logicalTarget <#TargetDump2>;
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" .
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Supergirl" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Sentinel" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Martian Manhunter" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Dreamer" .
+
+# file:///data/dump2.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" .
+ +

8.6 Subject Map and Graph Map

All triples containing the subject http://example.org/{@id} +are exported to TargetDump1 +and all triples within the named graph ex:Characters +are exported to TargetDump2.

+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+    rml:logicalTarget <#TargetDump1>;
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:graphMap [ a rml:GraphMap;
+      rml:logicalTarget <#TargetDump2>;
+      rml:constant ex:Characters;
+    ];
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname/text()";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nq
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" <http://example.org/Characters> .
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Supergirl" _b0 .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" <http://example.org/Characters> .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Sentinel" _b0 .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" <http://example.org/Characters> .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Martian Manhunter" _b0 .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" <http://example.org/Characters> .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Dreamer" _b0 .
+
+# file:///data/dump2.nq
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" <http://example.org/Characters> .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" <http://example.org/Characters> .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" <http://example.org/Characters> .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" <http://example.org/Characters> .
+ +

8.7 Predicate Map and Graph Map

All triples containing the predicate foaf:nickname +are exported to TargetDump1 +and all triples within the named graph ex:Characters +are exported to TargetDump2.

+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:graphMap [ a rml:GraphMap;
+      rml:logicalTarget <#TargetDump2>;
+      rml:constant ex:Characters;
+    ];
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+      rml:logicalTarget <#TargetDump1>;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname/text()";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nq
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Supergirl" _b0 .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Sentinel" _b0 .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Martian Manhunter" _b0 .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Dreamer" _b0 .
+
+# file:///data/dump2.nq
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" <http://example.org/Characters> .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" <http://example.org/Characters> .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" <http://example.org/Characters> .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" <http://example.org/Characters> .
+ +

8.8 Object Map and Graph Map

All triples containing the object reference nickname/text() +are exported to TargetDump1 +and all triples within the named graph ex:Characters +are exported to TargetDump2.

+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:graphMap [ a rml:GraphMap;
+      rml:logicalTarget <#TargetDump2>;
+      rml:constant ex:Characters;
+    ];
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname/text()";
+      rml:logicalTarget <#TargetDump1>;
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nq
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Supergirl" _b0 .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Sentinel" _b0 .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Martian Manhunter" _b0 .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Dreamer" _b0 .
+
+# file:///data/dump2.nq
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" <http://example.org/Characters> .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" <http://example.org/Characters> .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" <http://example.org/Characters> .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" <http://example.org/Characters> .
+ + +

8.9 Language Map and Graph Map

All triples containing the language tag en +are exported to TargetDump1 +and all triples within the named graph ex:Characters +are exported to TargetDump2. +The other triples are exported to the default target of the processor +as there is no dedicated Target assigned to triples containing +foaf:nickname as predicate.

+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:graphMap [ a rml:GraphMap;
+      rml:logicalTarget <#TargetDump2>;
+      rml:constant ex:Characters;
+    ];
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+      rml:languageMap [
+        rml:logicalTarget <#TargetDump1>;
+        rml:constant "en";
+      ];
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname/text()";
+      rml:logicalTarget <#TargetDump2>;
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers"@en <http://example.org/Characters> .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers"@en <http://example.org/Characters> .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz"@en <http://example.org/Characters> .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal"@en <http://example.org/Characters> .
+
+# file:///data/dump2.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers"@en <http://example.org/Characters> .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers"@en <http://example.org/Characters> .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz"@en <http://example.org/Characters> .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal"@en <http://example.org/Characters> .
+
+# default target of processor
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Supergirl" _b0 .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Sentinel" _b0 .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Martian Manhunter" _b0 .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Dreamer" _b0 .
+ +

8.10 Language Map and Object Map

All triples containing the language tag en +are exported to TargetDump1 +and all triples containing the object reference nickname/text() +are exported to TargetDump2.

+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+      rml:languageMap [
+        rml:logicalTarget <#TargetDump1>;
+        rml:constant "en";
+      ];
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname/text()";
+      rml:logicalTarget <#TargetDump2>;
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers"@en .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers"@en .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz"@en .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal"@en .
+
+# file:///data/dump2.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Supergirl" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Sentinel" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Martian Manhunter" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Dreamer" .
+ +

8.11 Multiple Predicate Maps

All triples containing the predicate foaf:name +are exported to TargetDump1 +and all triples containing the predicate foaf:nickname +are exported to TargetDump2.

+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+      rml:logicalTarget <#TargetDump1>;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+      rml:logicalTarget <#TargetDump2>;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname/text()";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" .
+
+# file:///data/dump2.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Supergirl" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Sentinel" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Martian Manhunter" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Dreamer" .
+ +

8.12 Multiple Object Maps

All triples containing the object reference name/text() +are exported to TargetDump1 +and all triples containing the object reference nickname/text() +are exported to TargetDump2.

+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+      rml:logicalTarget <#TargetDump1>;
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname/text()";
+      rml:logicalTarget <#TargetDump2>;
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" .
+
+# file:///data/dump2.nt
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Supergirl" .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Sentinel" .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Martian Manhunter" .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Dreamer" .
+ +

8.13 Multiple Graph Maps

All triples within the named graph ex:Characters +are exported to TargetDump1 +and all triples within the named graph ex:NickNames +are exported to TargetDump2.

+
<Supergirl>
+  <Character id="0">
+    <name>Kara Danvers</name>
+    <nickname>Supergirl</nickname>
+  </Character>
+  <Character id="1">
+    <name>Alex Danvers</name>
+    <nickname>Sentinel</nickname>
+  </Character>
+  <Character id="2">
+    <name>J'onn J'onzz</name>
+    <nickname>Martian Manhunter</nickname>
+  </Character>
+  <Character id="3">
+    <name>Nia Nal</name>
+    <nickname>Dreamer</nickname>
+  </Character>
+</Supergirl>
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "Supergirl.xml";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:XPath;
+    rml:iterator "//Supergirl/Character/";
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:template "http://example.org/{@id}";
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:graphMap [ a rml:GraphMap;
+      rml:logicalTarget <#TargetDump1>;
+      rml:constant ex:Characters;
+    ];
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name/text()";
+    ];
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:graphMap [ a rml:GraphMap;
+      rml:logicalTarget <#TargetDump2>;
+      rml:constant ex:NickNames;
+    ];
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:nickname;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "nickname/text()";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nq
+<http://example.org/0> <http://xmlns.com/foaf/0.1/name> "Kara Danvers" <http://example.org/Characters> .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/name> "Alex Danvers" <http://example.org/Characters> .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/name> "J'onn J'onzz" <http://example.org/Characters> .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Nia Nal" <http://example.org/Characters> .
+
+# file:///data/dump2.nq
+<http://example.org/0> <http://xmlns.com/foaf/0.1/nickname> "Supergirl" <http://example.org/Nicknames> .
+<http://example.org/1> <http://xmlns.com/foaf/0.1/nickname> "Sentinel" <http://example.org/Nicknames> .
+<http://example.org/2> <http://xmlns.com/foaf/0.1/nickname> "Martian Manhunter" <http://example.org/Nicknames> .
+<http://example.org/3> <http://xmlns.com/foaf/0.1/nickname> "Dreamer" <http://example.org/Nicknames> .
+ +

9. Overriding Targets

In some cases exporting all triples to a target is not desired, +therefore Targets can be overridden when needed +by either using a separate Triples Map which isolates certain triples or +by using FnO functions [FnO] as conditions.

+

9.1 Separate Triples Map

Triples can be exported to a specific Target while not to other Targets +by isolating these triples in a separate Triples Map.

+

In this example, the same subject and object are used in both Triples Maps, +but with a diffent predicate. The triples with the first predicate foaf:name +are exported to the first Target and the triples with the second predicate +schema:name to the second Target.

+
# DBPedia Friends actors as CSV
+actor,name,nickname
+http://dbpedia.org/resource/Kevin_Sussman,Kevin Sussman
+http://dbpedia.org/resource/Jim_Parsons,Jim Parsons
+http://dbpedia.org/resource/Kaley_Cuoco,Kaley Cuoco
+http://dbpedia.org/resource/Sara_Gilbert,Sara Gilbert
+http://dbpedia.org/resource/Kunal_Nayyar,Kunal Nayyar
+http://dbpedia.org/resource/Laura_Spencer_(actress),Laura Spencer
+http://dbpedia.org/resource/Simon_Helberg,Simon Helberg
+http://dbpedia.org/resource/Johnny_Galecki,Johnny Galecki
+http://dbpedia.org/resource/Mayim_Bialik,Mayim Bialik
+http://dbpedia.org/resource/Melissa_Rauch,Melissa Rauch
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "FriendsDBPedia.csv";
+.
+ +
<#TriplesMap1> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:CSV;
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:reference "actor";
+    rml:termType rml:IRI;
+    rml:logicalTarget <TargetDump1>;
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name";
+    ];
+  ];
+
+<#TriplesMap2> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <#SourceAccess>;
+    rml:referenceFormulation rml:CSV;
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:reference "actor";
+    rml:termType rml:IRI;
+    rml:logicalTarget <TargetDump2>;
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant schema:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name";
+    ];
+  ];
+.
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump2>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nt
+<http://dbpedia.org/resource/Kevin_Sussman> <http://xmlns.com/foaf/0.1/name> "Kevin Sussman" .
+<http://dbpedia.org/resource/Jim_Parsons> <http://xmlns.com/foaf/0.1/name> "Jim Parsons" .
+<http://dbpedia.org/resource/Kaley_Cuoco> <http://xmlns.com/foaf/0.1/name> "Kaley Cuoco" .
+<http://dbpedia.org/resource/Sara_Gilbert> <http://xmlns.com/foaf/0.1/name> "Sara Gilbert" .
+<http://dbpedia.org/resource/Kunal_Nayyar> <http://xmlns.com/foaf/0.1/name> "Kunal Nayyar" .
+<http://dbpedia.org/resource/Laura_Spencer> <http://xmlns.com/foaf/0.1/name> "Laura Spencer" .
+<http://dbpedia.org/resource/Simon_Helberg> <http://xmlns.com/foaf/0.1/name> "Simon Helberg" .
+<http://dbpedia.org/resource/Johnny_Galecki> <http://xmlns.com/foaf/0.1/name> "Johnny Galecki" .
+<http://dbpedia.org/resource/Mayim_Bialik> <http://xmlns.com/foaf/0.1/name> "Mayim Bialik" .
+<http://dbpedia.org/resource/Melissa_Rauch> <http://xmlns.com/foaf/0.1/name> "Melissa Rauch" .
+
+# file:///data/dump2.nt
+<http://dbpedia.org/resource/Kevin_Sussman> <http://schema.org/name> "Kevin Sussman" .
+<http://dbpedia.org/resource/Jim_Parsons> <http://schema.org/name> "Jim Parsons" .
+<http://dbpedia.org/resource/Kaley_Cuoco> <http://schema.org/name> "Kaley Cuoco" .
+<http://dbpedia.org/resource/Sara_Gilbert> <http://schema.org/name> "Sara Gilbert" .
+<http://dbpedia.org/resource/Kunal_Nayyar> <http://schema.org/name> "Kunal Nayyar" .
+<http://dbpedia.org/resource/Laura_Spencer> <http://schema.org/name> "Laura Spencer" .
+<http://dbpedia.org/resource/Simon_Helberg> <http://schema.org/name> "Simon Helberg" .
+<http://dbpedia.org/resource/Johnny_Galecki> <http://schema.org/name> "Johnny Galecki" .
+<http://dbpedia.org/resource/Mayim_Bialik> <http://schema.org/name> "Mayim Bialik" .
+<http://dbpedia.org/resource/Melissa_Rauch> <http://schema.org/name> "Melissa Rauch" .
+ +

9.2 Conditions

FnO functions MAY be leveraged to export triples +only under certain conditions. +Conditions are already integrated in RML+FnO processors, +thus conditions apply on Targets as well. +Triples are generated and exported based on the FnO condition's evaluation. +Only if the condition is true, the triples are generated and exported.

+

In the example, the triples with Jim Parsons as object are exported +to the first Target, triples with Kaley Cuoco as object are exported +to the second Target.

+
# DBPedia Friends actors as CSV
+actor,name,nickname
+http://dbpedia.org/resource/Kevin_Sussman,Kevin Sussman
+http://dbpedia.org/resource/Jim_Parsons,Jim Parsons
+http://dbpedia.org/resource/Kaley_Cuoco,Kaley Cuoco
+http://dbpedia.org/resource/Sara_Gilbert,Sara Gilbert
+http://dbpedia.org/resource/Kunal_Nayyar,Kunal Nayyar
+http://dbpedia.org/resource/Laura_Spencer_(actress),Laura Spencer
+http://dbpedia.org/resource/Simon_Helberg,Simon Helberg
+http://dbpedia.org/resource/Johnny_Galecki,Johnny Galecki
+http://dbpedia.org/resource/Mayim_Bialik,Mayim Bialik
+http://dbpedia.org/resource/Melissa_Rauch,Melissa Rauch
+ +
<#SourceAccess> a rml:Source, rml:FilePath;
+  rml:path "FriendsDBPedia.csv";
+.
+ +
<#TriplesMap> a rml:TriplesMap;
+  rml:logicalSource [ a rml:LogicalSource;
+    rml:source <SourceAccess>;
+    rml:referenceFormulation rml:CSV;
+  ];
+  rml:subjectMap [ a rml:SubjectMap;
+    rml:reference "actor";
+    rml:termType rml:IRI;
+    rml:logicalTarget <TargetDump1>;
+  ];
+  rml:predicateObjectMap [ a rml:PredicateObjectMap;
+    rml:predicateMap [ a rml:PredicateMap;
+      rml:constant foaf:name;
+    ];
+    rml:objectMap [ a rml:ObjectMap;
+      rml:reference "name";
+    ];
+  ];
+  rml:predicateObjectMap [
+    rml:predicateMap [ rml:constant foaf:name ];
+    rml:objectMap [
+      fnml:functionValue [
+        rml:predicateObjectMap [
+          rml:predicate fno:executes ;
+          rml:objectMap [ rml:constant idlab-fn:decide ]
+        ];
+        rml:predicateObjectMap [
+          rml:predicate idlab-fn:expectedStr ;
+          rml:objectMap [ rml:constant "Jim Parsons"]
+        ];
+        rml:predicateObjectMap [
+          rml:predicate idlab-fn:str ;
+          rml:objectMap [
+            rml:reference "name";
+            rml:logicalTarget <#TargetDump1>;
+          ];
+        ];
+      ];
+    ];
+  ];
+  rml:predicateObjectMap [
+    rml:predicateMap [ rml:constant foaf:name ];
+    rml:objectMap [
+      fnml:functionValue [
+        rml:predicateObjectMap [
+          rml:predicate fno:executes ;
+          rml:objectMap [ rml:constant idlab-fn:decide ]
+        ];
+        rml:predicateObjectMap [
+          rml:predicate idlab-fn:expectedStr ;
+          rml:objectMap [ rml:constant "Kaley Cuoco"]
+        ];
+        rml:predicateObjectMap [
+          rml:predicate idlab-fn:str ;
+          rml:objectMap [
+            rml:reference "name";
+            rml:logicalTarget <#TargetDump2>;
+          ];
+        ];
+      ];
+    ];
+  ];
+ +
<#TargetDump1> a rml:LogicalTarget;
+  rml:target <#Dump1>;
+  rml:serialization formats:N-Triples;
+.
+<#TargetDump2> a rml:LogicalTarget;
+  rml:target <#Dump2>;
+  rml:serialization formats:N-Triples;
+.
+ +
<#Dump1> a rml:Target, rml:FilePath;
+  rml:path "/data/dump1.nt";
+.
+<#Dump2> a rml:Target, rml:FilePath;
+  rml:path "/data/dump2.nt";
+.
+ +
# file:///data/dump1.nt
+<http://dbpedia.org/resource/Jim_Parsons> <http://xmlns.com/foaf/0.1/name> "Jim Parsons" .
+
+# file:///data/dump2.nt
+<http://dbpedia.org/resource/Kaley_Cuoco> <http://xmlns.com/foaf/0.1/name> "Kaley Cuoco" .
+ + + +

A. References

A.1 Normative references

+ +
[CSVW]
+ CSV on the Web: A Primer. Jeni Tennison. W3C. 25 February 2016. W3C Working Group Note. URL: https://www.w3.org/TR/tabular-data-primer/ +
[DCAT]
+ Data Catalog Vocabulary (DCAT) - Version 2. W3C. 22 February 2020. W3C Recommendation. URL: https://www.w3.org/TR/vocab-dcat/ +
[FnO]
+ Function Ontology (FnO). Ben De Meester; Anastasia Dimou; Florian Kleedorfer. IDLab - Ghent University - imec. 10 November 2021. Unofficial Draft. URL: https://w3id.org/function/spec +
[N-Quads]
+ RDF 1.1 N-Quads. W3C. 25 February 2014. W3C Recommendation. URL: https://www.w3.org/TR/n-quads/ +
[R2RML]
+ R2RML: RDB to RDF Mapping Language. Souripriya Das; Seema Sundara; Richard Cyganiak. W3C. 27 September 2012. W3C Recommendation. URL: https://www.w3.org/TR/r2rml/ +
[RDF-Concepts]
+ Resource Description Framework (RDF): Concepts and Abstract Syntax. Graham Klyne; Jeremy Carroll. W3C. 10 February 2004. W3C Recommendation. URL: https://www.w3.org/TR/rdf-concepts/ +
[RFC2119]
+ Key words for use in RFCs to Indicate Requirement Levels. S. Bradner. IETF. March 1997. Best Current Practice. URL: https://www.rfc-editor.org/rfc/rfc2119 +
[RFC8174]
+ Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words. B. Leiba. IETF. May 2017. Best Current Practice. URL: https://www.rfc-editor.org/rfc/rfc8174 +
[RML]
+ RDF Mapping Language (RML). Anastasia Dimou; Miel Vander Sande; Ben De Meester; Pieter Heyvaert; Thomas Delva. IDLab - Ghent University - imec. 16 November 2022. W3C Unofficial Draft. URL: https://rml.io/specs/rml +
[RML-Core]
+ RML-Core. W3C. 07 August 2024. Draft Community Group Report. URL: https://w3id.org/rml/core/spec +
[RML-IO-Registry]
+ Reference not found. +
[SD]
+ SPARQL 1.1 Service Description. W3C. 21 March 2013. W3C Recommendation. URL: https://www.w3.org/TR/sparql11-service-description/ +
[Turtle]
+ RDF 1.1 Turtle. W3C. 25 February 2014. W3C Recommendation. URL: https://www.w3.org/TR/turtle/ +
+
\ No newline at end of file diff --git a/spec/docs/index.html b/spec/docs/index.html index 9fe2d97..e991efd 100644 --- a/spec/docs/index.html +++ b/spec/docs/index.html @@ -1,5 +1,5 @@ - +