Accessors in Database and RegClass for new models

ForeignTable is simply represented by two accessors added to RegClass.
When foreign-table info is wanted, a little class RegClass holds in
a single slot gets instantiated and constructs both values.

The slot's invalidation still uses the RegClass switch point, rather
than also hooking invalidation for pg_foreign_table.

In passing, catch up with two pg_database attributes that changed
in PG 15 from name to text.

Author: jcflack

pljava-api/src/main/java/org/postgresql/pljava/model/Database.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022 Tada AB and other contributors, as listed below.
+ * Copyright (c) 2022-2025 Tada AB and other contributors, as listed below.
  *
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the The BSD 3-Clause License
@@ -56,5 +56,5 @@ public interface Database
 	// oid lastsysoid
 	// xid frozenxid
 	// xid minmxid
-	// oid tablespace
+	Tablespace tablespace();
 }

pljava-api/src/main/java/org/postgresql/pljava/model/RegClass.java

@@ -83,9 +83,16 @@ enum ReplicaIdentity { DEFAULT, NOTHING, ALL, INDEX }
 	 * associated with this relation.
 	 */
 	RegType ofType();
-	// am
-	// filenode
-	// tablespace
+
+	AccessMethod accessMethod();
+
+	/* Of limited interest ... used in forming pathname of relation on disk,
+	 * but in very fiddly ways and dependent on the access method.
+	 *
+	int filenode();
+	 */
+
+	Tablespace tablespace();
 
 	/* Of limited interest ... estimates used by planner
 	 *
@@ -129,5 +136,16 @@ enum ReplicaIdentity { DEFAULT, NOTHING, ALL, INDEX }
 	Map<Simple,String> options();
 	SQLXML partitionBound();
 
+	/**
+	 * The {@link ForeignServer} if this is a foreign table, otherwise null.
+	 */
+	ForeignServer foreignServer();
+
+	/**
+	 * Table options understood by the {@link #foreignServer foreign server}
+	 * if this is a foreign table, otherwise null.
+	 */
+	Map<Simple,String> foreignOptions();
+
 	TupleDescriptor.Interned tupleDescriptor();
 }

pljava-so/src/main/c/ModelConstants.c

@@ -35,6 +35,7 @@
 #include <catalog/pg_tablespace.h>
 #include <catalog/pg_foreign_data_wrapper.h>
 #include <catalog/pg_foreign_server.h>
+#include <catalog/pg_foreign_table.h>
 
 #include <commands/trigger.h>
 
@@ -279,6 +280,7 @@ static int32 constants[] = {
 	CONSTANT(TABLESPACEOID),
 	CONSTANT(FOREIGNDATAWRAPPEROID),
 	CONSTANT(FOREIGNSERVEROID),
+	CONSTANT(FOREIGNTABLEREL),
 
 
 
@@ -322,6 +324,7 @@ StaticAssertStmt((c) == \
 	CONFIRMCONST(           OperatorRelationId );
 	CONFIRMCONST(            TriggerRelationId );
 	CONFIRMCONST(          ExtensionRelationId );
+	CONFIRMCONST(       ForeignTableRelationId ); /* <-CatalogObjectImpl only */
 	CONFIRMCONST(          CollationRelationId );
 	CONFIRMCONST(          TransformRelationId );
 	CONFIRMCONST(       TSDictionaryRelationId );

pljava/src/main/java/org/postgresql/pljava/pg/CatalogObjectImpl.java

@@ -727,6 +727,12 @@ static Supplier<CatalogObjectImpl> typeConstructorFor(int oid)
 		@Native public static final int ANYCOMPATIBLENONARRAYOID      = 5079;
 		@Native public static final int ANYCOMPATIBLERANGEOID         = 5080;
 
+		/*
+		 * A relation ID that won't be used to construct a full-blown catalog
+		 * object, but used in RegClassImpl.
+		 */
+		@Native public static final int ForeignTableRelationId = 3118;
+
 		/*
 		 * Indices into arrays used for syscache invalidation callbacks.
 		 * One of these is a boolean native array the C callback can check

pljava/src/main/java/org/postgresql/pljava/pg/DatabaseImpl.java

@@ -21,6 +21,8 @@
 
 import java.util.function.Function;
 
+import org.postgresql.pljava.Adapter.As;
+
 import org.postgresql.pljava.internal.SwitchPointCache.Builder;
 import org.postgresql.pljava.internal.SwitchPointCache.SwitchPoint;
 
@@ -34,8 +36,10 @@
 import static org.postgresql.pljava.pg.adt.NameAdapter.SIMPLE_INSTANCE;
 import static org.postgresql.pljava.pg.adt.NameAdapter.AS_STRING_INSTANCE;
 import static org.postgresql.pljava.pg.adt.OidAdapter.REGROLE_INSTANCE;
+import static org.postgresql.pljava.pg.adt.OidAdapter.TABLESPACE_INSTANCE;
 import static org.postgresql.pljava.pg.adt.Primitives.BOOLEAN_INSTANCE;
 import static org.postgresql.pljava.pg.adt.Primitives.INT4_INSTANCE;
+import org.postgresql.pljava.pg.adt.TextAdapter;
 
 import org.postgresql.pljava.sqlgen.Lexicals.Identifier.Simple;
 import org.postgresql.pljava.sqlgen.Lexicals.Identifier.Unqualified;
@@ -49,6 +53,9 @@ class DatabaseImpl extends Addressed<Database>
 {
 	private static final Function<MethodHandle[],MethodHandle[]> s_initializer;
 
+	private static final As<String,?> COLLCTYPEADAPTER =
+		PG_VERSION_NUM >= 150000 ? TextAdapter.INSTANCE : AS_STRING_INSTANCE;
+
 	/* Implementation of Addressed */
 
 	@Override
@@ -101,6 +108,7 @@ private static List<CatalogObject.Grant> grants(DatabaseImpl o)
 	static final int SLOT_TEMPLATE;
 	static final int SLOT_ALLOWCONNECTION;
 	static final int SLOT_CONNECTIONLIMIT;
+	static final int SLOT_TABLESPACE;
 	static final int NSLOTS;
 
 	static
@@ -129,6 +137,7 @@ private static List<CatalogObject.Grant> grants(DatabaseImpl o)
 			.withDependent(       "template", SLOT_TEMPLATE        = i++)
 			.withDependent("allowConnection", SLOT_ALLOWCONNECTION = i++)
 			.withDependent("connectionLimit", SLOT_CONNECTIONLIMIT = i++)
+			.withDependent(     "tablespace", SLOT_TABLESPACE      = i++)
 
 			.build()
 			/*
@@ -149,6 +158,7 @@ static class Att
 		static final Attribute DATISTEMPLATE;
 		static final Attribute DATALLOWCONN;
 		static final Attribute DATCONNLIMIT;
+		static final Attribute DATTABLESPACE;
 
 		static
 		{
@@ -161,7 +171,8 @@ static class Att
 				"datctype",
 				"datistemplate",
 				"datallowconn",
-				"datconnlimit"
+				"datconnlimit",
+				"dattablespace"
 			).iterator();
 
 			DATNAME       = itr.next();
@@ -173,6 +184,7 @@ static class Att
 			DATISTEMPLATE = itr.next();
 			DATALLOWCONN  = itr.next();
 			DATCONNLIMIT  = itr.next();
+			DATTABLESPACE = itr.next();
 
 			assert ! itr.hasNext() : "attribute initialization miscount";
 		}
@@ -189,13 +201,13 @@ private static CharsetEncoding encoding(DatabaseImpl o) throws SQLException
 	private static String collate(DatabaseImpl o) throws SQLException
 	{
 		TupleTableSlot s = o.cacheTuple();
-		return s.get(Att.DATCOLLATE, AS_STRING_INSTANCE);
+		return s.get(Att.DATCOLLATE, COLLCTYPEADAPTER);
 	}
 
 	private static String ctype(DatabaseImpl o) throws SQLException
 	{
 		TupleTableSlot s = o.cacheTuple();
-		return s.get(Att.DATCTYPE, AS_STRING_INSTANCE);
+		return s.get(Att.DATCTYPE, COLLCTYPEADAPTER);
 	}
 
 	private static boolean template(DatabaseImpl o) throws SQLException
@@ -216,6 +228,12 @@ private static int connectionLimit(DatabaseImpl o) throws SQLException
 		return s.get(Att.DATCONNLIMIT, INT4_INSTANCE);
 	}
 
+	private static Tablespace tablespace(DatabaseImpl o) throws SQLException
+	{
+		TupleTableSlot s = o.cacheTuple();
+		return s.get(Att.DATTABLESPACE, TABLESPACE_INSTANCE);
+	}
+
 	/* API methods */
 
 	@Override
@@ -301,4 +319,18 @@ public int connectionLimit()
 			throw unchecked(t);
 		}
 	}
+
+	@Override
+	public Tablespace tablespace()
+	{
+		try
+		{
+			MethodHandle h = m_slots[SLOT_TABLESPACE];
+			return (Tablespace)h.invokeExact(this, h);
+		}
+		catch ( Throwable t )
+		{
+			throw unchecked(t);
+		}
+	}
 }

pljava/src/main/java/org/postgresql/pljava/pg/ModelConstants.java

@@ -376,6 +376,7 @@ public void close()
 
 	@Native private static final int IDX_FOREIGNDATAWRAPPEROID = 519;
 	@Native private static final int IDX_FOREIGNSERVEROID      = 520;
+	@Native private static final int IDX_FOREIGNTABLEREL       = 521;
 
 
 
@@ -573,6 +574,7 @@ public void close()
 
 	public static final int FOREIGNDATAWRAPPEROID; // ForeignDataWrapperImpl
 	public static final int FOREIGNSERVEROID;      // ForeignServerImpl
+	public static final int FOREIGNTABLEREL;       // RegClassImpl
 
 
 
@@ -772,6 +774,7 @@ public void close()
 
 			FOREIGNDATAWRAPPEROID = n.get(IDX_FOREIGNDATAWRAPPEROID);
 			FOREIGNSERVEROID      = n.get(IDX_FOREIGNSERVEROID);
+			FOREIGNTABLEREL       = n.get(IDX_FOREIGNTABLEREL);