* pg_hint_plan.c
* hinting on how to execute a query for PostgreSQL
*
- * Copyright (c) 2012-2020, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2012-2021, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
*
*-------------------------------------------------------------------------
*/
#define HINT_LEADING "Leading"
#define HINT_SET "Set"
#define HINT_ROWS "Rows"
+#define HINT_MEMOIZE "Memoize"
+#define HINT_NOMEMOIZE "NoMemoize"
#define HINT_ARRAY_DEFAULT_INITSIZE 8
{
ENABLE_NESTLOOP = 0x01,
ENABLE_MERGEJOIN = 0x02,
- ENABLE_HASHJOIN = 0x04
+ ENABLE_HASHJOIN = 0x04,
+ ENABLE_MEMOIZE = 0x08
} JOIN_TYPE_BITS;
#define ENABLE_ALL_SCAN (ENABLE_SEQSCAN | ENABLE_INDEXSCAN | \
HINT_KEYWORD_SET,
HINT_KEYWORD_ROWS,
HINT_KEYWORD_PARALLEL,
+ HINT_KEYWORD_MEMOIZE,
+ HINT_KEYWORD_NOMEMOIZE,
HINT_KEYWORD_UNRECOGNIZED
} HintKeyword;
Query *parse, const char *str);
/* hint types */
-#define NUM_HINT_TYPE 6
typedef enum HintType
{
HINT_TYPE_SCAN_METHOD,
HINT_TYPE_LEADING,
HINT_TYPE_SET,
HINT_TYPE_ROWS,
- HINT_TYPE_PARALLEL
+ HINT_TYPE_PARALLEL,
+ HINT_TYPE_MEMOIZE,
+
+ NUM_HINT_TYPE
} HintType;
typedef enum HintTypeBitmap
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.
+ * We can utilize in-core generated jumble state in post_parse_analyze_hook.
+ * On the other hand there's a case where we're forced to get hints in
+ * planner_hook, where we don't have a jumble state. If we a query had not a
+ * hint, we need to try to retrieve hints twice or more for one query, which is
+ * the quite common case. To avoid such case, this variables is set true when
+ * we *try* hint retrieval.
*/
static bool current_hint_retrieved = false;
JoinMethodHint **join_hints; /* parsed join hints */
int init_join_mask; /* initial value join parameter */
List **join_hint_level;
+ List **memoize_hint_level;
LeadingHint **leading_hint; /* parsed Leading hints */
SetHint **set_hints; /* parsed Set hints */
GucContext context; /* which GUC parameters can we set? */
RowsHint **rows_hints; /* parsed Rows hints */
ParallelHint **parallel_hints; /* parsed Parallel hints */
+ JoinMethodHint **memoize_hints; /* parsed Memoize hints */
};
/*
HintKeyword hint_keyword;
} HintParser;
+static bool enable_hint_table_check(bool *newval, void **extra, GucSource source);
+static void assign_enable_hint_table(bool newval, void *extra);
+
/* Module callbacks */
void _PG_init(void);
void _PG_fini(void);
static void push_hint(HintState *hstate);
static void pop_hint(void);
-static void pg_hint_plan_post_parse_analyze(ParseState *pstate, Query *query);
-static void pg_hint_plan_ProcessUtility(PlannedStmt *pstmt,
- const char *queryString,
- ProcessUtilityContext context,
- ParamListInfo params, QueryEnvironment *queryEnv,
- DestReceiver *dest, QueryCompletion *qc);
+static void pg_hint_plan_post_parse_analyze(ParseState *pstate, Query *query,
+ JumbleState *jstate);
static PlannedStmt *pg_hint_plan_planner(Query *parse, const char *query_string,
int cursorOptions,
ParamListInfo boundParams);
static const char *ParallelHintParse(ParallelHint *hint, HintState *hstate,
Query *parse, const char *str);
+static Hint *MemoizeHintCreate(const char *hint_str, const char *keyword,
+ HintKeyword hint_keyword);
+
static void quote_value(StringInfo buf, const char *value);
static const char *parse_quoted_value(const char *str, char **word,
static bool has_join_restriction(PlannerInfo *root, RelOptInfo *rel);
static void set_plain_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
RangeTblEntry *rte);
-static void set_append_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
- Index rti, RangeTblEntry *rte);
RelOptInfo *pg_hint_plan_make_join_rel(PlannerInfo *root, RelOptInfo *rel1,
RelOptInfo *rel2);
static int pg_hint_plan_debug_message_level = LOG;
/* Default is off, to keep backward compatibility. */
static bool pg_hint_plan_enable_hint_table = false;
+static bool pg_hint_plan_hints_anywhere = false;
static int plpgsql_recurse_level = 0; /* PLpgSQL recursion level */
static int recurse_level = 0; /* recursion level incl. direct SPI calls */
/* (This could not be above 1) */
static int max_hint_nworkers = -1; /* Maximum nworkers of Workers hints */
+static bool hint_table_deactivated = false;
+
static const struct config_enum_entry parse_messages_level_options[] = {
{"debug", DEBUG2, true},
{"debug5", DEBUG5, false},
static planner_hook_type prev_planner = NULL;
static join_search_hook_type prev_join_search = NULL;
static set_rel_pathlist_hook_type prev_set_rel_pathlist = NULL;
-static ProcessUtility_hook_type prev_ProcessUtility_hook = NULL;
/* Hold reference to currently active hint */
static HintState *current_hint_state = NULL;
{HINT_SET, SetHintCreate, HINT_KEYWORD_SET},
{HINT_ROWS, RowsHintCreate, HINT_KEYWORD_ROWS},
{HINT_PARALLEL, ParallelHintCreate, HINT_KEYWORD_PARALLEL},
+ {HINT_MEMOIZE, MemoizeHintCreate, HINT_KEYWORD_MEMOIZE},
+ {HINT_NOMEMOIZE, MemoizeHintCreate, HINT_KEYWORD_NOMEMOIZE},
{NULL, NULL, HINT_KEYWORD_UNRECOGNIZED}
};
false,
PGC_USERSET,
0,
+ enable_hint_table_check,
+ assign_enable_hint_table,
+ NULL);
+
+ DefineCustomBoolVariable("pg_hint_plan.hints_anywhere",
+ "Read hints from anywhere in a query.",
+ "This option lets pg_hint_plan ignore syntax so be cautious for false reads.",
+ &pg_hint_plan_hints_anywhere,
+ false,
+ PGC_USERSET,
+ 0,
NULL,
NULL,
NULL);
+ EmitWarningsOnPlaceholders("pg_hint_plan");
+
/* Install hooks. */
prev_post_parse_analyze_hook = post_parse_analyze_hook;
post_parse_analyze_hook = pg_hint_plan_post_parse_analyze;
join_search_hook = pg_hint_plan_join_search;
prev_set_rel_pathlist = set_rel_pathlist_hook;
set_rel_pathlist_hook = pg_hint_plan_set_rel_pathlist;
- 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");
PLpgSQL_plugin **var_ptr;
/* Uninstall hooks. */
- post_parse_analyze_hook = prev_post_parse_analyze_hook;
planner_hook = prev_planner;
join_search_hook = prev_join_search;
set_rel_pathlist_hook = prev_set_rel_pathlist;
- ProcessUtility_hook = prev_ProcessUtility_hook;
/* uninstall PL/pgSQL plugin hook */
var_ptr = (PLpgSQL_plugin **) find_rendezvous_variable("PLpgSQL_plugin");
*var_ptr = NULL;
}
+static bool
+enable_hint_table_check(bool *newval, void **extra, GucSource source)
+{
+ if (*newval)
+ {
+ EnableQueryId();
+
+ if (!IsQueryIdEnabled())
+ {
+ GUC_check_errmsg("table hint is not activated because queryid is not available");
+ GUC_check_errhint("Set compute_query_id to on or auto to use hint table.");
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static void
+assign_enable_hint_table(bool newval, void *extra)
+{
+ if (!newval)
+ hint_table_deactivated = false;
+}
+
/*
* create and delete functions the hint object
*/
}
+static Hint *
+MemoizeHintCreate(const char *hint_str, const char *keyword,
+ HintKeyword hint_keyword)
+{
+ /*
+ * MemoizeHintCreate shares the same struct with JoinMethodHint and the
+ * only difference is the hint type.
+ */
+ JoinMethodHint *hint =
+ (JoinMethodHint *)JoinMethodHintCreate(hint_str, keyword, hint_keyword);
+
+ hint->base.type = HINT_TYPE_MEMOIZE;
+
+ return (Hint *) hint;
+}
+
+
static HintState *
HintStateCreate(void)
{
hstate->join_hints = NULL;
hstate->init_join_mask = 0;
hstate->join_hint_level = NULL;
+ hstate->memoize_hint_level = NULL;
hstate->leading_hint = NULL;
hstate->context = superuser() ? PGC_SUSET : PGC_USERSET;
hstate->set_hints = NULL;
}
/*
- * Get client-supplied query string. Addtion to that the jumbled query is
- * supplied if the caller requested. From the restriction of JumbleQuery, some
- * kind of query needs special amendments. Reutrns NULL if this query doesn't
- * change the current hint. This function returns NULL also when something
- * wrong has happend and let the caller continue using the current hints.
- */
-static const char *
-get_query_string(ParseState *pstate, Query *query, Query **jumblequery)
-{
- const char *p = debug_query_string;
-
- /*
- * 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 or EXECUTE command. We may still see a
- * candidate top-level query in pstate in the case.
- */
- if (pstate && pstate->p_sourcetext)
- p = pstate->p_sourcetext;
-
- /* We don't see a query string, return NULL */
- if (!p)
- return NULL;
-
- if (jumblequery != NULL)
- *jumblequery = query;
-
- if (query->commandType == CMD_UTILITY)
- {
- Query *target_query = (Query *)query->utilityStmt;
-
- /*
- * Some CMD_UTILITY statements have a subquery that we can hint on.
- * Since EXPLAIN can be placed before other kind of utility statements
- * and EXECUTE can be contained other kind of utility statements, these
- * conditions are not mutually exclusive and should be considered in
- * this order.
- */
- if (IsA(target_query, ExplainStmt))
- {
- ExplainStmt *stmt = (ExplainStmt *)target_query;
-
- Assert(IsA(stmt->query, Query));
- target_query = (Query *)stmt->query;
-
- /* strip out the top-level query for further processing */
- if (target_query->commandType == CMD_UTILITY &&
- target_query->utilityStmt != NULL)
- target_query = (Query *)target_query->utilityStmt;
- }
-
- if (IsA(target_query, DeclareCursorStmt))
- {
- DeclareCursorStmt *stmt = (DeclareCursorStmt *)target_query;
- Query *query = (Query *)stmt->query;
-
- /* the target must be CMD_SELECT in this case */
- Assert(IsA(query, Query) && query->commandType == CMD_SELECT);
- target_query = query;
- }
-
- if (IsA(target_query, CreateTableAsStmt))
- {
- CreateTableAsStmt *stmt = (CreateTableAsStmt *) target_query;
-
- Assert(IsA(stmt->query, Query));
- target_query = (Query *) stmt->query;
-
- /* strip out the top-level query for further processing */
- if (target_query->commandType == CMD_UTILITY &&
- target_query->utilityStmt != NULL)
- target_query = (Query *)target_query->utilityStmt;
- }
-
- if (IsA(target_query, ExecuteStmt))
- {
- /*
- * Use the prepared query for EXECUTE. The Query for jumble
- * also replaced with the corresponding one.
- */
- ExecuteStmt *stmt = (ExecuteStmt *)target_query;
- PreparedStatement *entry;
-
- entry = FetchPreparedStatement(stmt->name, true);
-
- if (entry->plansource->is_valid)
- {
- p = entry->plansource->query_string;
- target_query = (Query *) linitial (entry->plansource->query_list);
- }
- else
- {
- /* igonre the hint for EXECUTE if invalidated */
- p = NULL;
- target_query = NULL;
- }
- }
-
- /* JumbleQuery accespts only a non-utility Query */
- if (target_query &&
- (!IsA(target_query, Query) ||
- target_query->utilityStmt != NULL))
- target_query = NULL;
-
- if (jumblequery)
- *jumblequery = target_query;
- }
- /*
- * 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;
-}
-
-/*
* Get hints from the head block comment in client-supplied query string.
*/
static const char *
hint_head = strstr(p, HINT_START);
if (hint_head == NULL)
return NULL;
- for (;p < hint_head; p++)
+ if (!pg_hint_plan_hints_anywhere)
{
- /*
- * Allow these characters precedes hint comment:
- * - digits
- * - alphabets which are in ASCII range
- * - space, tabs and new-lines
- * - underscores, for identifier
- * - commas, for SELECT clause, EXPLAIN and PREPARE
- * - parentheses, for EXPLAIN and PREPARE
- *
- * Note that we don't use isalpha() nor isalnum() in ctype.h here to
- * avoid behavior which depends on locale setting.
- */
- if (!(*p >= '0' && *p <= '9') &&
- !(*p >= 'A' && *p <= 'Z') &&
- !(*p >= 'a' && *p <= 'z') &&
- !isspace(*p) &&
- *p != '_' &&
- *p != ',' &&
- *p != '(' && *p != ')')
- return NULL;
+ for (;p < hint_head; p++)
+ {
+ /*
+ * Allow these characters precedes hint comment:
+ * - digits
+ * - alphabets which are in ASCII range
+ * - space, tabs and new-lines
+ * - underscores, for identifier
+ * - commas, for SELECT clause, EXPLAIN and PREPARE
+ * - parentheses, for EXPLAIN and PREPARE
+ *
+ * Note that we don't use isalpha() nor isalnum() in ctype.h here to
+ * avoid behavior which depends on locale setting.
+ */
+ if (!(*p >= '0' && *p <= '9') &&
+ !(*p >= 'A' && *p <= 'Z') &&
+ !(*p >= 'a' && *p <= 'z') &&
+ !isspace(*p) &&
+ *p != '_' &&
+ *p != ',' &&
+ *p != '(' && *p != ')')
+ return NULL;
+ }
}
- len = strlen(HINT_START);
- head = (char *) p;
- p += len;
+ head = (char *)hint_head;
+ p = head + strlen(HINT_START);
skip_space(p);
/* find hint end keyword. */
hstate->num_hints[HINT_TYPE_SET]);
hstate->parallel_hints = (ParallelHint **) (hstate->rows_hints +
hstate->num_hints[HINT_TYPE_ROWS]);
+ hstate->memoize_hints = (JoinMethodHint **) (hstate->parallel_hints +
+ hstate->num_hints[HINT_TYPE_PARALLEL]);
return hstate;
}
case HINT_KEYWORD_NOHASHJOIN:
hint->enforce_mask = ENABLE_ALL_JOIN ^ ENABLE_HASHJOIN;
break;
+ case HINT_KEYWORD_MEMOIZE:
+ case HINT_KEYWORD_NOMEMOIZE:
+ /* nothing to do here */
+ break;
default:
hint_ereport(str, ("Unrecognized hint keyword \"%s\".", keyword));
return NULL;
hint->base.keyword));
else if (nworkers < 0)
hint_ereport(hint->nworkers_str,
- ("number of workers must be positive: %s",
+ ("number of workers must be greater than zero: %s",
hint->base.keyword));
else if (nworkers > max_worker_processes)
hint_ereport(hint->nworkers_str,
mask |= ENABLE_MERGEJOIN;
if (enable_hashjoin)
mask |= ENABLE_HASHJOIN;
+ if (enable_memoize)
+ mask |= ENABLE_MEMOIZE;
return mask;
}
}
static void
-set_join_config_options(unsigned char enforce_mask, GucContext context)
+set_join_config_options(unsigned char enforce_mask, bool set_memoize,
+ GucContext context)
{
unsigned char mask;
SET_CONFIG_OPTION("enable_mergejoin", ENABLE_MERGEJOIN);
SET_CONFIG_OPTION("enable_hashjoin", ENABLE_HASHJOIN);
+ if (set_memoize)
+ SET_CONFIG_OPTION("enable_memoize", ENABLE_MEMOIZE);
+
/*
* Hash join may be rejected for the reason of estimated memory usage. Try
* getting rid of that limitation.
* Retrieve and store hint string from given query or from the hint table.
*/
static void
-get_current_hint_string(ParseState *pstate, Query *query)
+get_current_hint_string(Query *query, const char *query_str,
+ JumbleState *jstate)
{
- const char *query_str;
MemoryContext oldcontext;
- /* do nothing under hint table search */
- if (hint_inhibit_level > 0)
- return;
+ /* We shouldn't get here for internal queries. */
+ Assert (hint_inhibit_level == 0);
+
+ /* We shouldn't get here if hint is disabled. */
+ Assert (pg_hint_plan_enable_hint);
- /* We alredy have one, don't parse it again. */
+ /* Do not anything if we have already tried to get hints for this query. */
if (current_hint_retrieved)
return;
+ /* No way to retrieve hints from empty string. */
+ if (!query_str)
+ return;
+
/* Don't parse the current query hereafter */
current_hint_retrieved = true;
- if (!pg_hint_plan_enable_hint)
+ /* Make sure trashing old hint string */
+ if (current_hint_str)
{
- if (current_hint_str)
- {
- pfree((void *)current_hint_str);
- current_hint_str = NULL;
- }
- return;
+ pfree((void *)current_hint_str);
+ current_hint_str = NULL;
}
/* increment the query number */
/* search the hint table for a hint if requested */
if (pg_hint_plan_enable_hint_table)
{
- int query_len;
- pgssJumbleState jstate;
- Query *jumblequery;
- char *normalized_query = NULL;
-
- query_str = get_query_string(pstate, query, &jumblequery);
+ int query_len;
+ char *normalized_query;
- /* If this query is not for hint, just return */
- if (!query_str)
- return;
-
- /* clear the previous hint string */
- if (current_hint_str)
+ if (!IsQueryIdEnabled())
{
- pfree((void *)current_hint_str);
- current_hint_str = NULL;
- }
-
- if (jumblequery)
- {
- /*
- * 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;
- jstate.clocations_buf_size = 32;
- jstate.clocations = (pgssLocationLen *)
- palloc(jstate.clocations_buf_size * sizeof(pgssLocationLen));
- jstate.clocations_count = 0;
-
- JumbleQuery(&jstate, jumblequery);
-
- /*
- * Normalize the query string by replacing constants with '?'
- */
/*
- * Search hint string which is stored keyed by query string
- * and application name. The query string is normalized to allow
- * fuzzy matching.
- *
- * Adding 1 byte to query_len ensures that the returned string has
- * a terminating NULL.
+ * compute_query_id was turned off while enable_hint_table is
+ * on. Do not go ahead and complain once until it is turned on
+ * again.
*/
- query_len = strlen(query_str) + 1;
- normalized_query =
- generate_normalized_query(&jstate, query_str, 0, &query_len,
- GetDatabaseEncoding());
+ if (!hint_table_deactivated)
+ ereport(WARNING,
+ (errmsg ("hint table feature is deactivated because queryid is not available"),
+ errhint("Set compute_query_id to \"auto\" or \"on\" to use hint table.")));
- /*
- * find a hint for the normalized query. the result should be in
- * TopMemoryContext
- */
- oldcontext = MemoryContextSwitchTo(TopMemoryContext);
- current_hint_str =
- get_hints_from_table(normalized_query, application_name);
- MemoryContextSwitchTo(oldcontext);
+ hint_table_deactivated = true;
+ return;
+ }
- if (debug_level > 1)
- {
- if (current_hint_str)
- ereport(pg_hint_plan_debug_message_level,
- (errmsg("pg_hint_plan[qno=0x%x]: "
- "post_parse_analyze_hook: "
- "hints from table: \"%s\": "
- "normalized_query=\"%s\", "
- "application name =\"%s\"",
- qno, current_hint_str,
- normalized_query, application_name),
- errhidestmt(msgqno != qno),
- errhidecontext(msgqno != qno)));
- else
- ereport(pg_hint_plan_debug_message_level,
- (errmsg("pg_hint_plan[qno=0x%x]: "
- "no match found in table: "
- "application name = \"%s\", "
- "normalized_query=\"%s\"",
- qno, application_name,
- normalized_query),
- errhidestmt(msgqno != qno),
- errhidecontext(msgqno != qno)));
-
- msgqno = qno;
- }
+ if (hint_table_deactivated)
+ {
+ ereport(LOG, (errmsg ("hint table feature is reactivated")));
+ hint_table_deactivated = false;
}
- /* retrun if we have hint here */
- if (current_hint_str)
+ if (!jstate)
+ jstate = JumbleQuery(query, query_str);
+
+ if (!jstate)
return;
- }
- else
- query_str = get_query_string(pstate, query, NULL);
- if (query_str)
- {
/*
- * get hints from the comment. However we may have the same query
- * string with the previous call, but the extra comparison seems no
- * use..
+ * Normalize the query string by replacing constants with '?'
*/
- if (current_hint_str)
- pfree((void *)current_hint_str);
+ /*
+ * Search hint string which is stored keyed by query string
+ * and application name. The query string is normalized to allow
+ * fuzzy matching.
+ *
+ * Adding 1 byte to query_len ensures that the returned string has
+ * a terminating NULL.
+ */
+ query_len = strlen(query_str) + 1;
+ normalized_query =
+ generate_normalized_query(jstate, query_str, 0, &query_len);
- oldcontext = MemoryContextSwitchTo(TopMemoryContext);
- current_hint_str = get_hints_from_comment(query_str);
- MemoryContextSwitchTo(oldcontext);
- }
- else
- {
/*
- * Failed to get query. We would be in fetching invalidated
- * plancache. Try the next chance.
+ * find a hint for the normalized query. the result should be in
+ * TopMemoryContext
*/
- current_hint_retrieved = false;
+ oldcontext = MemoryContextSwitchTo(TopMemoryContext);
+ current_hint_str =
+ get_hints_from_table(normalized_query, application_name);
+ MemoryContextSwitchTo(oldcontext);
+
+ if (debug_level > 1)
+ {
+ if (current_hint_str)
+ ereport(pg_hint_plan_debug_message_level,
+ (errmsg("pg_hint_plan[qno=0x%x]: "
+ "hints from table: \"%s\": "
+ "normalized_query=\"%s\", "
+ "application name =\"%s\"",
+ qno, current_hint_str,
+ normalized_query, application_name),
+ errhidestmt(msgqno != qno),
+ errhidecontext(msgqno != qno)));
+ else
+ ereport(pg_hint_plan_debug_message_level,
+ (errmsg("pg_hint_plan[qno=0x%x]: "
+ "no match found in table: "
+ "application name = \"%s\", "
+ "normalized_query=\"%s\"",
+ qno, application_name,
+ normalized_query),
+ errhidestmt(msgqno != qno),
+ errhidecontext(msgqno != qno)));
+
+ msgqno = qno;
+ }
+
+ /* retrun if we have hint string here */
+ if (current_hint_str)
+ return;
}
+ /* get hints from the comment */
+ oldcontext = MemoryContextSwitchTo(TopMemoryContext);
+ current_hint_str = get_hints_from_comment(query_str);
+ MemoryContextSwitchTo(oldcontext);
+
if (debug_level > 1)
{
- if (debug_level == 1 && query_str && debug_query_string &&
+ if (debug_level == 2 && query_str && debug_query_string &&
strcmp(query_str, debug_query_string))
ereport(pg_hint_plan_debug_message_level,
(errmsg("hints in comment=\"%s\"",
* Retrieve hint string from the current query.
*/
static void
-pg_hint_plan_post_parse_analyze(ParseState *pstate, Query *query)
+pg_hint_plan_post_parse_analyze(ParseState *pstate, Query *query,
+ JumbleState *jstate)
{
if (prev_post_parse_analyze_hook)
- prev_post_parse_analyze_hook(pstate, query);
+ prev_post_parse_analyze_hook(pstate, query, jstate);
+
+ if (!pg_hint_plan_enable_hint || hint_inhibit_level > 0)
+ return;
/* 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(PlannedStmt *pstmt, const char *queryString,
- ProcessUtilityContext context,
- ParamListInfo params, QueryEnvironment *queryEnv,
- DestReceiver *dest, QueryCompletion *qc)
-{
- if (prev_ProcessUtility_hook)
- prev_ProcessUtility_hook(pstmt, queryString, context, params, queryEnv,
- dest, qc);
- else
- standard_ProcessUtility(pstmt, queryString, context, params, queryEnv,
- dest, qc);
-
- if (plpgsql_recurse_level == 0)
- current_hint_retrieved = false;
+ /*
+ * Jumble state is required when hint table is used. This is the only
+ * chance to have one already generated in-core. If it's not the case, no
+ * use to do the work now and pg_hint_plan_planner() will do the all work.
+ */
+ if (jstate)
+ get_current_hint_string(query, pstate->p_sourcetext, jstate);
}
/*
}
/*
- * Support for nested plpgsql functions. This is quite ugly but this is the
- * only point I could find where I can get the query string.
+ * SQL commands invoked in plpgsql functions may also have hints. In that
+ * case override the upper level hint by the new hint.
*/
- if (plpgsql_recurse_level > 0 &&
- error_context_stack && error_context_stack->arg)
+ if (plpgsql_recurse_level > 0)
{
- MemoryContext oldcontext;
+ const char *tmp_hint_str = current_hint_str;
- oldcontext = MemoryContextSwitchTo(TopMemoryContext);
- current_hint_str =
- get_hints_from_comment((char *)error_context_stack->arg);
- MemoryContextSwitchTo(oldcontext);
- }
+ /* don't let get_current_hint_string free this string */
+ current_hint_str = NULL;
- /*
- * 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);
+ current_hint_retrieved = false;
- /* No hint, go the normal way */
+ get_current_hint_string(parse, query_string, NULL);
+
+ if (current_hint_str == NULL)
+ current_hint_str = tmp_hint_str;
+ else if (tmp_hint_str != NULL)
+ pfree((void *)tmp_hint_str);
+ }
+ else
+ get_current_hint_string(parse, query_string, NULL);
+
+ /* No hints, go the normal way */
if (!current_hint_str)
goto standard_planner_proc;
/* parse the hint into hint state struct */
hstate = create_hintstate(parse, pstrdup(current_hint_str));
- /* run standard planner if the statement has not valid hint */
+ /* run standard planner if we're given with no valid hints */
if (!hstate)
+ {
+ /* forget invalid hint string */
+ if (current_hint_str)
+ {
+ pfree((void *)current_hint_str);
+ current_hint_str = NULL;
+ }
+
goto standard_planner_proc;
+ }
/*
* Push new hint struct to the hint stack to disable previous hint context.
{
/*
* Rollback changes of GUC parameters, and pop current hint context
- * from hint stack to rewind the state.
+ * from hint stack to rewind the state. current_hint_str will be freed
+ * by context deletion.
*/
current_hint_str = prev_hint_str;
recurse_level--;
/*
* current_hint_str is useless after planning of the top-level query.
+ * There's a case where the caller has multiple queries. This causes hint
+ * parsing multiple times for the same string but we don't have a simple
+ * and reliable way to distinguish that case from the case where of
+ * separate queries.
*/
- if (recurse_level < 1 && current_hint_str)
- {
- pfree((void *)current_hint_str);
- current_hint_str = NULL;
+ if (recurse_level < 1)
current_hint_retrieved = false;
- }
/* Print hint in debug mode. */
if (debug_level == 1)
pfree(indexname);
}
- if (debug_level == 1)
+ if (debug_level > 0)
{
StringInfoData rel_buf;
char *disprelname = "";
return 0;
}
- /*
- * Forget about the parent of another subquery, but don't forget if the
- * inhTargetkind of the root is not INHKIND_NONE, which signals the root
- * contains only appendrel members. See inheritance_planner for details.
- *
- * (PG12.0) 428b260f87 added one more planning cycle for updates on
- * partitioned tables and hints set up in the cycle are overriden by the
- * second cycle. Since I didn't find no apparent distinction between the
- * PlannerRoot of the cycle and that of ordinary CMD_SELECT, pg_hint_plan
- * accepts both cycles and the later one wins. In the second cycle root
- * doesn't have inheritance information at all so use the parent_relid set
- * in the first cycle.
- */
- if (root->inhTargetKind == INHKIND_NONE)
+ if (bms_num_members(rel->top_parent_relids) == 1)
{
- if (root != current_hint_state->current_root)
- current_hint_state->parent_relid = 0;
-
- /* Find the parent for this relation other than the registered parent */
- foreach (l, root->append_rel_list)
- {
- AppendRelInfo *appinfo = (AppendRelInfo *) lfirst(l);
-
- if (appinfo->child_relid == rel->relid)
- {
- if (current_hint_state->parent_relid != appinfo->parent_relid)
- {
- new_parent_relid = appinfo->parent_relid;
- current_hint_state->current_root = root;
- }
- break;
- }
- }
-
- if (!l)
- {
- /*
- * This relation doesn't have a parent. Cancel
- * current_hint_state.
- */
- current_hint_state->parent_relid = 0;
- current_hint_state->parent_scan_hint = NULL;
- current_hint_state->parent_parallel_hint = NULL;
- }
+ new_parent_relid = bms_next_member(rel->top_parent_relids, -1);
+ current_hint_state->current_root = root;
+ Assert(new_parent_relid > 0);
+ }
+ else
+ {
+ /* This relation doesn't have a parent. Cancel current_hint_state. */
+ current_hint_state->parent_relid = 0;
+ current_hint_state->parent_scan_hint = NULL;
+ current_hint_state->parent_parallel_hint = NULL;
}
if (new_parent_relid > 0)
return NULL;
}
+
+/*
+ * Return memoize hint which matches given joinrelids.
+ */
+static JoinMethodHint *
+find_memoize_hint(Relids joinrelids)
+{
+ List *join_hint;
+ ListCell *l;
+
+ join_hint = current_hint_state->memoize_hint_level[bms_num_members(joinrelids)];
+
+ foreach(l, join_hint)
+ {
+ JoinMethodHint *hint = (JoinMethodHint *) lfirst(l);
+
+ if (bms_equal(joinrelids, hint->joinrelids))
+ return hint;
+ }
+
+ return NULL;
+}
+
+
static Relids
OuterInnerJoinCreate(OuterInnerRels *outer_inner, LeadingHint *leading_hint,
PlannerInfo *root, List *initial_rels, HintState *hstate, int nbaserel)
lappend(hstate->join_hint_level[hint->nrels], hint);
}
+ /* ditto for memoize hints */
+ for (i = 0; i < hstate->num_hints[HINT_TYPE_MEMOIZE]; i++)
+ {
+ JoinMethodHint *hint = hstate->join_hints[i];
+
+ if (!hint_state_enabled(hint) || hint->nrels > nbaserel)
+ continue;
+
+ hint->joinrelids = create_bms_of_relids(&(hint->base), root,
+ initial_rels, hint->nrels, hint->relnames);
+
+ if (hint->joinrelids == NULL || hint->base.state == HINT_STATE_ERROR)
+ continue;
+
+ hstate->memoize_hint_level[hint->nrels] =
+ lappend(hstate->memoize_hint_level[hint->nrels], hint);
+ }
+
/*
* Create bitmap of relids from alias names for each rows hint.
* Bitmaps are more handy than strings in join searching.
if (hint_state_enabled(lhint))
{
- set_join_config_options(DISABLE_ALL_JOIN, current_hint_state->context);
+ set_join_config_options(DISABLE_ALL_JOIN, false,
+ current_hint_state->context);
return true;
}
return false;
make_join_rel_wrapper(PlannerInfo *root, RelOptInfo *rel1, RelOptInfo *rel2)
{
Relids joinrelids;
- JoinMethodHint *hint;
+ JoinMethodHint *join_hint;
+ JoinMethodHint *memoize_hint;
RelOptInfo *rel;
int save_nestlevel;
joinrelids = bms_union(rel1->relids, rel2->relids);
- hint = find_join_hint(joinrelids);
+ join_hint = find_join_hint(joinrelids);
+ memoize_hint = find_memoize_hint(joinrelids);
bms_free(joinrelids);
- if (!hint)
- return pg_hint_plan_make_join_rel(root, rel1, rel2);
+ /* reject non-matching hints */
+ if (join_hint && join_hint->inner_nrels != 0)
+ join_hint = NULL;
+
+ if (memoize_hint && memoize_hint->inner_nrels != 0)
+ memoize_hint = NULL;
- if (hint->inner_nrels == 0)
+ if (join_hint || memoize_hint)
{
save_nestlevel = NewGUCNestLevel();
- set_join_config_options(hint->enforce_mask,
- current_hint_state->context);
+ if (join_hint)
+ set_join_config_options(join_hint->enforce_mask, false,
+ current_hint_state->context);
- rel = pg_hint_plan_make_join_rel(root, rel1, rel2);
- hint->base.state = HINT_STATE_USED;
+ if (memoize_hint)
+ {
+ bool memoize =
+ memoize_hint->base.hint_keyword == HINT_KEYWORD_MEMOIZE;
+ set_config_option_noerror("enable_memoize",
+ memoize ? "true" : "false",
+ current_hint_state->context,
+ PGC_S_SESSION, GUC_ACTION_SAVE,
+ true, ERROR);
+ }
+ }
+
+ /* do the work */
+ rel = pg_hint_plan_make_join_rel(root, rel1, rel2);
+
+ /* Restore the GUC variables we set above. */
+ if (join_hint || memoize_hint)
+ {
+ if (join_hint)
+ join_hint->base.state = HINT_STATE_USED;
+
+ if (memoize_hint)
+ memoize_hint->base.state = HINT_STATE_USED;
- /*
- * Restore the GUC variables we set above.
- */
AtEOXact_GUC(true, save_nestlevel);
}
- else
- rel = pg_hint_plan_make_join_rel(root, rel1, rel2);
return rel;
}
{
Relids joinrelids;
JoinMethodHint *join_hint;
+ JoinMethodHint *memoize_hint;
int save_nestlevel;
joinrelids = bms_union(outerrel->relids, innerrel->relids);
join_hint = find_join_hint(joinrelids);
+ memoize_hint = find_memoize_hint(joinrelids);
bms_free(joinrelids);
- if (join_hint && join_hint->inner_nrels != 0)
+ /* reject the found hints if they don't match this join */
+ if (join_hint && join_hint->inner_nrels == 0)
+ join_hint = NULL;
+
+ if (memoize_hint && memoize_hint->inner_nrels == 0)
+ memoize_hint = NULL;
+
+ /* set up configuration if needed */
+ if (join_hint || memoize_hint)
{
save_nestlevel = NewGUCNestLevel();
- if (bms_equal(join_hint->inner_joinrelids, innerrel->relids))
+ if (join_hint)
{
-
- set_join_config_options(join_hint->enforce_mask,
- current_hint_state->context);
-
- add_paths_to_joinrel(root, joinrel, outerrel, innerrel, jointype,
- sjinfo, restrictlist);
- join_hint->base.state = HINT_STATE_USED;
+ if (bms_equal(join_hint->inner_joinrelids, innerrel->relids))
+ set_join_config_options(join_hint->enforce_mask, false,
+ current_hint_state->context);
+ else
+ set_join_config_options(DISABLE_ALL_JOIN, false,
+ current_hint_state->context);
}
- else
+
+ if (memoize_hint)
{
- set_join_config_options(DISABLE_ALL_JOIN,
- current_hint_state->context);
- add_paths_to_joinrel(root, joinrel, outerrel, innerrel, jointype,
- sjinfo, restrictlist);
+ bool memoize =
+ memoize_hint->base.hint_keyword == HINT_KEYWORD_MEMOIZE;
+ set_config_option_noerror("enable_memoize",
+ memoize ? "true" : "false",
+ current_hint_state->context,
+ PGC_S_SESSION, GUC_ACTION_SAVE,
+ true, ERROR);
}
+ }
+
+ /* generate paths */
+ add_paths_to_joinrel(root, joinrel, outerrel, innerrel, jointype,
+ sjinfo, restrictlist);
+
+ /* restore GUC variables */
+ if (join_hint || memoize_hint)
+ {
+ if (join_hint)
+ join_hint->base.state = HINT_STATE_USED;
+
+ if (memoize_hint)
+ memoize_hint->base.state = HINT_STATE_USED;
- /*
- * Restore the GUC variables we set above.
- */
AtEOXact_GUC(true, save_nestlevel);
}
- else
- add_paths_to_joinrel(root, joinrel, outerrel, innerrel, jointype,
- sjinfo, restrictlist);
}
static int
current_hint_state->join_hint_level =
palloc0(sizeof(List *) * (nbaserel + 1));
join_method_hints = palloc0(sizeof(JoinMethodHint *) * (nbaserel + 1));
+ current_hint_state->memoize_hint_level =
+ palloc0(sizeof(List *) * (nbaserel + 1));
leading_hint_enable = transform_join_hints(current_hint_state,
root, nbaserel,
pfree(join_method_hints);
if (leading_hint_enable)
- set_join_config_options(current_hint_state->init_join_mask,
+ set_join_config_options(current_hint_state->init_join_mask, true,
current_hint_state->context);
return rel;
}
/*
- * set_rel_pathlist
- * Build access paths for a base relation
- *
- * This function was copied and edited from set_rel_pathlist() in
- * src/backend/optimizer/path/allpaths.c in order not to copy other static
- * functions not required here.
- */
-static void
-set_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
- Index rti, RangeTblEntry *rte)
-{
- if (IS_DUMMY_REL(rel))
- {
- /* We already proved the relation empty, so nothing more to do */
- }
- else if (rte->inh)
- {
- /* It's an "append relation", process accordingly */
- set_append_rel_pathlist(root, rel, rti, rte);
- }
- else
- {
- if (rel->rtekind == RTE_RELATION)
- {
- if (rte->relkind == RELKIND_RELATION)
- {
- if(rte->tablesample != NULL)
- elog(ERROR, "sampled relation is not supported");
-
- /* Plain relation */
- set_plain_rel_pathlist(root, rel, rte);
- }
- else
- elog(ERROR, "unexpected relkind: %c", rte->relkind);
- }
- else
- elog(ERROR, "unexpected rtekind: %d", (int) rel->rtekind);
- }
-
- /*
- * Allow a plugin to editorialize on the set of Paths for this base
- * relation. It could add new paths (such as CustomPaths) by calling
- * add_path(), or delete or modify paths added by the core code.
- */
- if (set_rel_pathlist_hook)
- (*set_rel_pathlist_hook) (root, rel, rti, rte);
-
- /* Now find the cheapest of the paths for this rel */
- set_cheapest(rel);
-}
-
-/*
* stmt_beg callback is called when each query in PL/pgSQL function is about
* to be executed. At that timing, we save query string in the global variable
* plpgsql_query_string to use it in planner hook. It's safe to use one global
plpgsql_recurse_level = 0;
}
+
+/* include core static functions */
+static void populate_joinrel_with_paths(PlannerInfo *root, RelOptInfo *rel1,
+ RelOptInfo *rel2, RelOptInfo *joinrel,
+ SpecialJoinInfo *sjinfo, List *restrictlist);
+static void set_append_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
+ Index rti, RangeTblEntry *rte);
+
#define standard_join_search pg_hint_plan_standard_join_search
#define join_search_one_level pg_hint_plan_join_search_one_level
#define make_join_rel make_join_rel_wrapper
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