Function postgresImportForeignSchema

contrib/postgres_fdw/postgres_fdw.c:5238–5536

* Import a foreign schema */

 * Import a foreign schema
 */
static List *
postgresImportForeignSchema(ImportForeignSchemaStmt *stmt, Oid serverOid)
{
	List	   *commands = NIL;
	bool		import_collate = true;
	bool		import_default = false;
	bool		import_generated = true;
	bool		import_not_null = true;
	ForeignServer *server;
	UserMapping *mapping;
	PGconn	   *conn;
	StringInfoData buf;
	PGresult   *volatile res = NULL;
	int			numrows,
				i;
	ListCell   *lc;

	/* Parse statement options */
	foreach(lc, stmt->options)
	{
		DefElem    *def = (DefElem *) lfirst(lc);

		if (strcmp(def->defname, "import_collate") == 0)
			import_collate = defGetBoolean(def);
		else if (strcmp(def->defname, "import_default") == 0)
			import_default = defGetBoolean(def);
		else if (strcmp(def->defname, "import_generated") == 0)
			import_generated = defGetBoolean(def);
		else if (strcmp(def->defname, "import_not_null") == 0)
			import_not_null = defGetBoolean(def);
		else
			ereport(ERROR,
					(errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
					 errmsg("invalid option \"%s\"", def->defname)));
	}

	/*
	 * Get connection to the foreign server.  Connection manager will
	 * establish new connection if necessary.
	 */
	server = GetForeignServer(serverOid);
	mapping = GetUserMapping(GetUserId(), server->serverid);
	conn = GetConnection(mapping, false, NULL);

	/* Don't attempt to import collation if remote server hasn't got it */
	if (PQserverVersion(conn) < 90100)
		import_collate = false;

	/* Create workspace for strings */
	initStringInfo(&buf);

	/* In what follows, do not risk leaking any PGresults. */
	PG_TRY();
	{
		/* Check that the schema really exists */
		appendStringInfoString(&buf, "SELECT 1 FROM pg_catalog.pg_namespace WHERE nspname = ");
		deparseStringLiteral(&buf, stmt->remote_schema);