From: Shigeru Hanada <hanada@metrosystems.co.jp>
Date: Thu, 18 Nov 2010 09:54:43 +0000 (+0900)
Subject: Separate function to generate SQL statement in postgresql_fdw.
X-Git-Url: http://git.postgresql.org/gitweb/static/gitweb.js?a=commitdiff_plain;h=c58cd58c63f333c0cc51a9b820c93585a4e603d7;p=users%2Fhanada%2Fpostgres.git

Separate function to generate SQL statement in postgresql_fdw.

Conflicts:

	contrib/postgresql_fdw/postgresql_fdw.c
---

diff --git a/contrib/postgresql_fdw/postgresql_fdw.c b/contrib/postgresql_fdw/postgresql_fdw.c
index 49d2868b33..9aa460e29f 100644
--- a/contrib/postgresql_fdw/postgresql_fdw.c
+++ b/contrib/postgresql_fdw/postgresql_fdw.c
@@ -42,20 +42,19 @@ extern Datum postgresql_fdw_handler(PG_FUNCTION_ARGS);
  */
 static FSConnection* pgConnectServer(ForeignServer *server, UserMapping *user);
 static void pgFreeFSConnection(FSConnection *conn);
+static void pgEstimateCosts(ForeignPath *path, PlannerInfo *root, RelOptInfo *baserel);
 static void pgOpen(ForeignScanState *scanstate);
 static void pgBeginScan(ForeignScanState *scanstate);
 static void pgIterate(ForeignScanState *scanstate);
 static void pgClose(ForeignScanState *scanstate);
 static void pgReOpen(ForeignScanState *scanstate);
-static void pgEstimateCosts(ForeignPath *path, PlannerInfo *root, RelOptInfo *baserel);
 
 /* helper for deparsing a request into SQL statement */
 static bool is_immutable_func(Oid funcid);
 static bool is_foreign_qual(Expr *expr);
 static bool foreign_qual_walker(Node *node, void *context);
-static void deparseSelectFrom(StringInfo sql, ForeignTable *table,
-							  TupleDesc tupdesc, const char *aliasname,
-							  bool prefix);
+static void deparseSelectClause(StringInfo sql, ForeignTable *table, TupleDesc tupdesc, const char *aliasname, bool prefix);
+static void deparseFromClause(StringInfo sql, ForeignTable *table, const char *aliasname, bool prefix);
 static char *deparseSql(ForeignScanState *scanstate);
 
 /* helper for handling result tuples */
@@ -240,20 +239,16 @@ foreign_qual_walker(Node *node, void *context)
 }
 
 /*
- * Deparse the passed TupleDesc into SELECT & FROM clauses and append to sql.
+ * Deparse the passed TupleDesc into SELECT clauses and append to the buffer
+ * 'sql'.
  */
 static void
-deparseSelectFrom(StringInfo sql, ForeignTable *table, TupleDesc tupdesc,
-				  const char *aliasname, bool prefix)
+deparseSelectClause(StringInfo sql, ForeignTable *table, TupleDesc tupdesc,
+					const char *aliasname, bool prefix)
 {
 	bool			first;
 	int				i;
-	char		   *nspname = NULL;
-	char		   *relname = NULL;
-	const char	   *nspname_q;
-	const char	   *relname_q;
 	const char	   *aliasname_q;
-	ListCell	   *lc;
 
 	/* The alias of relation is used in both SELECT clause and FROM clause. */
 	aliasname_q = quote_identifier(aliasname);
@@ -309,6 +304,27 @@ deparseSelectFrom(StringInfo sql, ForeignTable *table, TupleDesc tupdesc,
 	if (first)
 		appendStringInfo(sql, "NULL");
 
+	if (aliasname_q != aliasname)
+		pfree((char *) aliasname_q);
+}
+
+/*
+ * Deparse the passed information into FROM clauses and append to the buffer
+ * 'sql'.
+ */
+static void
+deparseFromClause(StringInfo sql, ForeignTable *table, const char *aliasname, bool prefix)
+{
+	char		   *nspname = NULL;
+	char		   *relname = NULL;
+	const char	   *nspname_q;
+	const char	   *relname_q;
+	const char	   *aliasname_q;
+	ListCell	   *lc;
+
+	/* The alias of relation is used in both SELECT clause and FROM clause. */
+	aliasname_q = quote_identifier(aliasname);
+
 	/* deparse FROM clause */
 	appendStringInfo(sql, " FROM ");
 
@@ -378,8 +394,9 @@ deparseSql(ForeignScanState *scanstate)
 	prefix = list_length(estate->es_range_table) > 1;
 
 	/* deparse SELECT and FROM clauses */
-	deparseSelectFrom(&sql, table, scanstate->ss.ss_currentRelation->rd_att,
-					  rte->eref->aliasname, prefix);
+	deparseSelectClause(&sql, table, scanstate->ss.ss_currentRelation->rd_att,
+						rte->eref->aliasname, prefix);
+	deparseFromClause(&sql, table, rte->eref->aliasname, prefix);
 
 	/*
 	 * deparse WHERE cluase