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docs/graphql/index.md

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+# GraphQL over SPARQL
+
+This section describes out approach to generate JSON responses from SPARQL endpoints using GraphQL as a query and mapping language.
+Mutations are not supported.
+The GraphQL queries of our approach are self-contained, i.e. no additional server configuration is needed. The endpoint is avilable when running [`rpt integrate --server`](../integrate), by default [http://localhost:8642/graphql](http://localhost:8642/graphql).
+From each GraphQL query a corresponding SPARQL query and result set post processor is created.
+
+## Examples
+
+Check out the [demonstrators](../demos) for examples.
+
+## Directives
+
+The following is the set of supported directives:
+
+[`@prefix`](prefix) [`@pattern`](pattern) [`@one and `@many`](one-and-many) [`@index`](index-directive) [`@join`](join)