Set query ID for inner queries of CREATE TABLE AS and DECLARE

Some utility statements contain queries that can be planned and
executed: CREATE TABLE AS and DECLARE CURSOR.  This commit adds query ID
computation for the inner queries executed by these two utility
commands, with and without EXPLAIN.  This change leads to four new
callers of JumbleQuery() and post_parse_analyze_hook() so as extensions
can decide what to do with this new data.

Previously, extensions relying on the query ID, like pg_stat_statements,
were not able to track these nested queries as the query_id was 0.

For pg_stat_statements, this commit leads to additions under !toplevel
when pg_stat_statements.track is set to "all", as shown in its
regression tests.  The output of EXPLAIN for these two utilities gains a
"Query Identifier" if compute_query_id is enabled.

Author: Anthonin Bonnefoy
Reviewed-by: Michael Paquier, Jian He
Discussion: https://postgr.es/m/CAO6_XqqM6S9bQ2qd=75W+yKATwoazxSNhv5sjW06fjGAtHbTUA@mail.gmail.com

1 files changed, 9 insertions, 11 deletions

diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 07257d4db94..a93f970a292 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -561,13 +561,12 @@ DropAllPreparedStatements(void)
  * "into" is NULL unless we are doing EXPLAIN CREATE TABLE AS EXECUTE,
  * in which case executing the query should result in creating that table.
  *
- * Note: the passed-in queryString is that of the EXPLAIN EXECUTE,
+ * Note: the passed-in pstate's queryString is that of the EXPLAIN EXECUTE,
  * not the original PREPARE; we get the latter string from the plancache.
  */
 void
 ExplainExecuteQuery(ExecuteStmt *execstmt, IntoClause *into, ExplainState *es,
-					const char *queryString, ParamListInfo params,
-					QueryEnvironment *queryEnv)
+					ParseState *pstate, ParamListInfo params)
 {
 	PreparedStatement *entry;
 	const char *query_string;
@@ -610,10 +609,10 @@ ExplainExecuteQuery(ExecuteStmt *execstmt, IntoClause *into, ExplainState *es,
 	/* Evaluate parameters, if any */
 	if (entry->plansource->num_params)
 	{
-		ParseState *pstate;
+		ParseState *pstate_params;
 
-		pstate = make_parsestate(NULL);
-		pstate->p_sourcetext = queryString;
+		pstate_params = make_parsestate(NULL);
+		pstate_params->p_sourcetext = pstate->p_sourcetext;
 
 		/*
 		 * Need an EState to evaluate parameters; must not delete it till end
@@ -624,12 +623,12 @@ ExplainExecuteQuery(ExecuteStmt *execstmt, IntoClause *into, ExplainState *es,
 		estate = CreateExecutorState();
 		estate->es_param_list_info = params;
 
-		paramLI = EvaluateParams(pstate, entry, execstmt->params, estate);
+		paramLI = EvaluateParams(pstate_params, entry, execstmt->params, estate);
 	}
 
 	/* Replan if needed, and acquire a transient refcount */
 	cplan = GetCachedPlan(entry->plansource, paramLI,
-						  CurrentResourceOwner, queryEnv);
+						  CurrentResourceOwner, pstate->p_queryEnv);
 
 	INSTR_TIME_SET_CURRENT(planduration);
 	INSTR_TIME_SUBTRACT(planduration, planstart);
@@ -655,12 +654,11 @@ ExplainExecuteQuery(ExecuteStmt *execstmt, IntoClause *into, ExplainState *es,
 		PlannedStmt *pstmt = lfirst_node(PlannedStmt, p);
 
 		if (pstmt->commandType != CMD_UTILITY)
-			ExplainOnePlan(pstmt, into, es, query_string, paramLI, queryEnv,
+			ExplainOnePlan(pstmt, into, es, query_string, paramLI, pstate->p_queryEnv,
 						   &planduration, (es->buffers ? &bufusage : NULL),
 						   es->memory ? &mem_counters : NULL);
 		else
-			ExplainOneUtility(pstmt->utilityStmt, into, es, query_string,
-							  paramLI, queryEnv);
+			ExplainOneUtility(pstmt->utilityStmt, into, es, pstate, paramLI);
 
 		/* No need for CommandCounterIncrement, as ExplainOnePlan did it */