static char qnostr[32];
static const char *current_hint_str = NULL;
+/*
+ * However we usually take a hint stirng in post_parse_analyze_hook, we still
+ * need to do so in planner_hook when client starts query execution from the
+ * bind message on a prepared query. This variable prevent duplicate and
+ * sometimes harmful hint string retrieval.
+ */
+static bool current_hint_retrieved = false;
+
/* common data for all hints. */
struct Hint
{
static void pop_hint(void);
static void pg_hint_plan_post_parse_analyze(ParseState *pstate, Query *query);
+static void pg_hint_plan_ProcessUtility(Node *parsetree,
+ const char *queryString,
+ ProcessUtilityContext context, ParamListInfo params,
+ DestReceiver *dest, char *completionTag);
static PlannedStmt *pg_hint_plan_planner(Query *parse, int cursorOptions,
ParamListInfo boundParams);
static void pg_hint_plan_get_relation_info(PlannerInfo *root,
static planner_hook_type prev_planner = NULL;
static get_relation_info_hook_type prev_get_relation_info = NULL;
static join_search_hook_type prev_join_search = NULL;
+static ProcessUtility_hook_type prev_ProcessUtility_hook = NULL;
/* Hold reference to currently active hint */
static HintState *current_hint = NULL;
get_relation_info_hook = pg_hint_plan_get_relation_info;
prev_join_search = join_search_hook;
join_search_hook = pg_hint_plan_join_search;
+ prev_ProcessUtility_hook = ProcessUtility_hook;
+ ProcessUtility_hook = pg_hint_plan_ProcessUtility;
/* setup PL/pgSQL plugin hook */
var_ptr = (PLpgSQL_plugin **) find_rendezvous_variable("PLpgSQL_plugin");
planner_hook = prev_planner;
get_relation_info_hook = prev_get_relation_info;
join_search_hook = prev_join_search;
+ ProcessUtility_hook = prev_ProcessUtility_hook;
/* uninstall PL/pgSQL plugin hook */
var_ptr = (PLpgSQL_plugin **) find_rendezvous_variable("PLpgSQL_plugin");
/*
* If debug_query_string is set, it is the top level statement. But in some
* cases we reach here with debug_query_string set NULL for example in the
- * case of DESCRIBE message handling. We may still see a candidate
- * top-level query in pstate in the case.
+ * case of DESCRIBE message handling or EXECUTE command. We may still see a
+ * candidate top-level query in pstate in the case.
*/
- if (!p)
- {
- /* We don't see a query string, return NULL */
- if (!pstate->p_sourcetext)
- return NULL;
-
+ if (!p && pstate)
p = pstate->p_sourcetext;
- }
+
+ /* We don't see a query string, return NULL */
+ if (!p)
+ return NULL;
if (jumblequery != NULL)
*jumblequery = query;
if (jumblequery)
*jumblequery = target_query;
}
-
- /* Return NULL if the pstate is not identical to the top-level query */
- else if (strcmp(pstate->p_sourcetext, p) != 0)
+ /*
+ * Return NULL if pstate is not of top-level query. We don't need this
+ * when jumble info is not requested or cannot do this when pstate is NULL.
+ */
+ else if (!jumblequery && pstate && pstate->p_sourcetext != p &&
+ strcmp(pstate->p_sourcetext, p) != 0)
p = NULL;
return p;
}
/*
- * We need only jumbled query for the root query, acquired by
- * get_query_string(). We cannot check that in pg_hint_plan_planner since it
- * cannot see the truely corresponding query string to the given Query.
- * We check that here instead using ParseState.
+ * Retrieve and store hint string from given query or from the hint table.
*/
static void
-pg_hint_plan_post_parse_analyze(ParseState *pstate, Query *query)
+get_current_hint_string(ParseState *pstate, Query *query)
{
const char *query_str;
MemoryContext oldcontext;
- if (prev_post_parse_analyze_hook)
- prev_post_parse_analyze_hook(pstate, query);
-
/* do nothing under hint table search */
if (hint_inhibit_level > 0)
return;
+ /* We alredy have one, don't parse it again. */
+ if (current_hint_retrieved)
+ return;
+
+ /* Don't parse the current query hereafter */
+ current_hint_retrieved = true;
+
if (!pg_hint_plan_enable_hint)
{
if (current_hint_str)
if (jumblequery)
{
/*
- * XXX: normalizing code is copied from pg_stat_statements.c, so be
- * careful to PostgreSQL's version up.
+ * XXX: normalization code is copied from pg_stat_statements.c.
+ * Make sure to keep up-to-date with it.
*/
jstate.jumble = (unsigned char *) palloc(JUMBLE_SIZE);
jstate.jumble_len = 0;
{
/*
* get hints from the comment. However we may have the same query
- * string with the previous call, but just retrieving hints is expected
- * to be faster than checking for identicalness before retrieval.
+ * string with the previous call, but the extra comparison seems no
+ * use..
*/
if (current_hint_str)
pfree((void *)current_hint_str);
}
/*
+ * Retrieve hint string from the current query.
+ */
+static void
+pg_hint_plan_post_parse_analyze(ParseState *pstate, Query *query)
+{
+ if (prev_post_parse_analyze_hook)
+ prev_post_parse_analyze_hook(pstate, query);
+
+ /* always retrieve hint from the top-level query string */
+ if (plpgsql_recurse_level == 0)
+ current_hint_retrieved = false;
+
+ get_current_hint_string(pstate, query);
+}
+
+/*
+ * We need to reset current_hint_retrieved flag always when a command execution
+ * is finished. This is true even for a pure utility command that doesn't
+ * involve planning phase.
+ */
+static void
+pg_hint_plan_ProcessUtility(Node *parsetree, const char *queryString,
+ ProcessUtilityContext context, ParamListInfo params,
+ DestReceiver *dest, char *completionTag)
+{
+ if (prev_ProcessUtility_hook)
+ prev_ProcessUtility_hook(parsetree, queryString, context, params,
+ dest, completionTag);
+
+ if (plpgsql_recurse_level == 0)
+ current_hint_retrieved = false;
+}
+
+/*
* Read and set up hint information
*/
static PlannedStmt *
MemoryContextSwitchTo(oldcontext);
}
+ /*
+ * Query execution in extended protocol can be started without the analyze
+ * phase. In the case retrieve hint string here.
+ */
+ if (!current_hint_str)
+ get_current_hint_string(NULL, parse);
+
+ /* No hint, go the normal way */
if (!current_hint_str)
goto standard_planner_proc;
}
PG_END_TRY();
+
+ /*
+ * current_hint_str is useless after planning of the top-level query.
+ */
+ if (plpgsql_recurse_level < 1 && current_hint_str)
+ {
+ pfree((void *)current_hint_str);
+ current_hint_str = NULL;
+ current_hint_retrieved = false;
+ }
+
/* Print hint in debug mode. */
if (debug_level == 1)
HintStateDump(current_hint);
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