From: Shigeru Hanada <hanada@metrosystems.co.jp>
Date: Tue, 18 Jan 2011 10:51:34 +0000 (+0900)
Subject: Add catalog lookup function for pg_foreign_table.
X-Git-Url: http://waps.l3s.uni-hannover.de/gitweb/?a=commitdiff_plain;h=830170525e225400e7d6dddf5cb01be9fc1a69e7;p=users%2Fhanada%2Fpostgres.git

Add catalog lookup function for pg_foreign_table.
---

diff --git a/src/backend/foreign/foreign.c b/src/backend/foreign/foreign.c
index 9a0f847f93..6cfddf317a 100644
--- a/src/backend/foreign/foreign.c
+++ b/src/backend/foreign/foreign.c
@@ -16,6 +16,7 @@
 #include "catalog/namespace.h"
 #include "catalog/pg_foreign_data_wrapper.h"
 #include "catalog/pg_foreign_server.h"
+#include "catalog/pg_foreign_table.h"
 #include "catalog/pg_type.h"
 #include "catalog/pg_user_mapping.h"
 #include "foreign/foreign.h"
@@ -249,6 +250,45 @@ GetUserMapping(Oid userid, Oid serverid)
 }
 
 
+/*
+ * GetForeignTable - look up the foreign table definition by relation oid.
+ */
+ForeignTable *
+GetForeignTable(Oid relid)
+{
+	Form_pg_foreign_table tableform;
+	ForeignTable *ft;
+	HeapTuple	tp;
+	Datum		datum;
+	bool		isnull;
+
+	tp = SearchSysCache(FOREIGNTABLEREL,
+						ObjectIdGetDatum(relid),
+						0, 0, 0);
+
+	if (!HeapTupleIsValid(tp))
+		elog(ERROR, "cache lookup failed for foreign table %u", relid);
+
+	tableform = (Form_pg_foreign_table) GETSTRUCT(tp);
+
+	ft = palloc(sizeof(ForeignTable));
+	ft->relid = relid;
+	ft->serverid = tableform->ftserver;
+
+	/* Extract the ftoptions */
+	datum = SysCacheGetAttr(FOREIGNTABLEREL,
+							tp,
+							Anum_pg_foreign_table_ftoptions,
+							&isnull);
+
+	/* untransformRelOptions does exactly what we want - avoid duplication */
+	ft->options = untransformRelOptions(datum);
+	ReleaseSysCache(tp);
+
+	return ft;
+}
+
+
 /*
  * deflist_to_tuplestore - Helper function to convert DefElem list to
  * tuplestore usable in SRF.
diff --git a/src/include/foreign/foreign.h b/src/include/foreign/foreign.h
index 2d1495cfe1..f3037a442a 100644
--- a/src/include/foreign/foreign.h
+++ b/src/include/foreign/foreign.h
@@ -59,6 +59,12 @@ typedef struct UserMapping
 	List	   *options;		/* useoptions as DefElem list */
 } UserMapping;
 
+typedef struct ForeignTable
+{
+	Oid			relid;			/* relation Oid */
+	Oid			serverid;		/* server Oid */
+	List	   *options;		/* ftoptions as DefElem list */
+} ForeignTable;
 
 extern ForeignServer *GetForeignServer(Oid serverid);
 extern ForeignServer *GetForeignServerByName(const char *name, bool missing_ok);
@@ -68,5 +74,6 @@ extern ForeignDataWrapper *GetForeignDataWrapper(Oid fdwid);
 extern ForeignDataWrapper *GetForeignDataWrapperByName(const char *name,
 							bool missing_ok);
 extern Oid	GetForeignDataWrapperOidByName(const char *name, bool missing_ok);
+extern ForeignTable *GetForeignTable(Oid relid);
 
 #endif   /* FOREIGN_H */