utility db function for statement sql table

nomenklatura/statement/__init__.py

@@ -1,15 +1,18 @@
 from nomenklatura.statement.statement import Statement, StatementDict
-from nomenklatura.statement.serialize import CSV, JSON, FORMATS
+from nomenklatura.statement.serialize import CSV, JSON, PACK, FORMATS
 from nomenklatura.statement.serialize import write_statements
 from nomenklatura.statement.serialize import read_statements, read_path_statements
+from nomenklatura.statement.db import make_statement_table
 
 __all__ = [
     "Statement",
     "StatementDict",
     "CSV",
     "JSON",
+    "PACK",
     "FORMATS",
     "write_statements",
     "read_statements",
+    "make_statement_table",
     "read_path_statements",
 ]

nomenklatura/statement/db.py

@@ -0,0 +1,25 @@
+from sqlalchemy import MetaData, Table, Column, DateTime, Unicode, Boolean
+
+KEY_LEN = 255
+VALUE_LEN = 65535
+
+
+def make_statement_table(metadata: MetaData, name: str = "statement") -> Table:
+    return Table(
+        name,
+        metadata,
+        Column("id", Unicode(KEY_LEN), primary_key=True, unique=True),
+        Column("entity_id", Unicode(KEY_LEN), index=True, nullable=False),
+        Column("canonical_id", Unicode(KEY_LEN), index=True, nullable=True),
+        Column("prop", Unicode(KEY_LEN), nullable=False),
+        Column("prop_type", Unicode(KEY_LEN), nullable=False),
+        Column("schema", Unicode(KEY_LEN), nullable=False),
+        Column("value", Unicode(VALUE_LEN), nullable=False),
+        Column("original_value", Unicode(VALUE_LEN), nullable=True),
+        Column("dataset", Unicode(KEY_LEN), index=True),
+        Column("lang", Unicode(KEY_LEN), nullable=True),
+        Column("target", Boolean, default=False, nullable=False),
+        Column("external", Boolean, default=False, nullable=False),
+        Column("first_seen", DateTime, nullable=False),
+        Column("last_seen", DateTime, index=True),
+    )