/*-------------------------------------------------------------------------
*
* pg_hint_plan.c
- * Track statement execution in current/last transaction.
+ * do instructions or hints to the planner using C-style block comments
+ * of the SQL.
*
- * Copyright (c) 2011, PostgreSQL Global Development Group
- *
- * IDENTIFICATION
- * contrib/pg_hint_plan/pg_hint_plan.c
+ * Copyright (c) 2012, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
-#include "fmgr.h"
-#include "utils/elog.h"
-#include "utils/builtins.h"
-#include "utils/memutils.h"
-#include "optimizer/cost.h"
+#include "miscadmin.h"
+#include "optimizer/geqo.h"
+#include "optimizer/joininfo.h"
+#include "optimizer/pathnode.h"
+#include "optimizer/paths.h"
+#include "optimizer/plancat.h"
+#include "optimizer/planner.h"
+#include "tcop/tcopprot.h"
+#include "utils/lsyscache.h"
#ifdef PG_MODULE_MAGIC
PG_MODULE_MAGIC;
#endif
-#define HASH_ENTRIES 201
+#if PG_VERSION_NUM != 90200
+#error unsupported PostgreSQL version
+#endif
+
+#define HINT_START "/*"
+#define HINT_END "*/"
+
+/* hint keywords */
+#define HINT_SEQSCAN "SeqScan"
+#define HINT_INDEXSCAN "IndexScan"
+#define HINT_BITMAPSCAN "BitmapScan"
+#define HINT_TIDSCAN "TidScan"
+#define HINT_NOSEQSCAN "NoSeqScan"
+#define HINT_NOINDEXSCAN "NoIndexScan"
+#define HINT_NOBITMAPSCAN "NoBitmapScan"
+#define HINT_NOTIDSCAN "NoTidScan"
+#define HINT_NESTLOOP "NestLoop"
+#define HINT_MERGEJOIN "MergeJoin"
+#define HINT_HASHJOIN "HashJoin"
+#define HINT_NONESTLOOP "NoNestLoop"
+#define HINT_NOMERGEJOIN "NoMergeJoin"
+#define HINT_NOHASHJOIN "NoHashJoin"
+#define HINT_LEADING "Leading"
+#define HINT_SET "Set"
+
+#if PG_VERSION_NUM >= 90200
+#define HINT_INDEXONLYSCAN "IndexonlyScan"
+#define HINT_NOINDEXONLYSCAN "NoIndexonlyScan"
+#endif
+
+#define HINT_ARRAY_DEFAULT_INITSIZE 8
+
+#define parse_ereport(str, detail) \
+ ereport(pg_hint_plan_parse_message, \
+ (errmsg("hint syntax error at or near \"%s\"", (str)), \
+ errdetail detail))
+
+#define skip_space(str) \
+ while (isspace(*str)) \
+ str++;
enum
{
ENABLE_HASHJOIN = 0x40
} TYPE_BITS;
-typedef struct tidlist
+#define ENABLE_ALL_SCAN (ENABLE_SEQSCAN | ENABLE_INDEXSCAN | ENABLE_BITMAPSCAN \
+ | ENABLE_TIDSCAN)
+#define ENABLE_ALL_JOIN (ENABLE_NESTLOOP | ENABLE_MERGEJOIN | ENABLE_HASHJOIN)
+
+/* scan method hints */
+typedef struct ScanHint
{
- int nrels;
- Oid *oids;
-} TidList;
+ const char *opt_str; /* must not do pfree */
+ char *relname;
+ List *indexnames;
+ unsigned char enforce_mask;
+} ScanHint;
+
+/* join method hints */
+typedef struct JoinHint
+{
+ const char *opt_str; /* must not do pfree */
+ int nrels;
+ char **relnames;
+ unsigned char enforce_mask;
+ Relids joinrelids;
+} JoinHint;
+
+/* change a run-time parameter hints */
+typedef struct SetHint
+{
+ char *name; /* name of variable */
+ char *value;
+} SetHint;
-typedef struct hash_entry
+typedef struct PlanHint
{
- TidList tidlist;
- unsigned char enforce_mask;
- struct hash_entry *next;
-} HashEntry;
+ char *hint_str;
-static HashEntry *hashent[HASH_ENTRIES];
-#ifdef NOT_USED
-static bool (*org_cost_hook)(CostHookType type, PlannerInfo *root, Path *path1, Path *path2);
-#endif
-static bool print_log = false;
-static bool tweak_enabled = true;
+ int nscan_hints;
+ int max_scan_hints;
+ ScanHint **scan_hints;
+
+ int njoin_hints;
+ int max_join_hints;
+ JoinHint **join_hints;
+
+ int nlevel;
+ List **join_hint_level;
+
+ List *leading;
+
+ GucContext context;
+ List *set_hints;
+} PlanHint;
+
+typedef const char *(*HintParserFunction) (PlanHint *plan, Query *parse, char *keyword, const char *str);
+
+typedef struct HintParser
+{
+ char *keyword;
+ bool have_paren;
+ HintParserFunction hint_parser;
+} HintParser;
/* Module callbacks */
void _PG_init(void);
void _PG_fini(void);
-Datum pg_add_hint(PG_FUNCTION_ARGS);
-Datum pg_clear_hint(PG_FUNCTION_ARGS);
-Datum pg_dump_hint(PG_FUNCTION_ARGS);
-Datum pg_enable_hint(bool arg, bool *isnull);
-Datum pg_enable_log(bool arg, bool *isnull);
+static PlannedStmt *pg_hint_plan_planner(Query *parse, int cursorOptions,
+ ParamListInfo boundParams);
+static void pg_hint_plan_get_relation_info(PlannerInfo *root, Oid relationObjectId,
+ bool inhparent, RelOptInfo *rel);
+static RelOptInfo *pg_hint_plan_join_search(PlannerInfo *root, int levels_needed,
+ List *initial_rels);
+
+static const char *ParseScanMethod(PlanHint *plan, Query *parse, char *keyword, const char *str);
+static const char *ParseIndexScanMethod(PlanHint *plan, Query *parse, char *keyword, const char *str);
+static const char *ParseSet(PlanHint *plan, Query *parse, char *keyword, const char *str);
#ifdef NOT_USED
-static char *rels_str(PlannerInfo *root, Path *path);
-static void dump_rels(char *label, PlannerInfo *root, Path *path, bool found, bool enabled);
-static void dump_joinrels(char *label, PlannerInfo *root, Path *inpath, Path *outpath, bool found, bool enabled);
-static bool my_cost_hook(CostHookType type, PlannerInfo *root, Path *path1, Path *path2);
-#endif
-static void free_hashent(HashEntry *head);
-static unsigned int calc_hash(TidList *tidlist);
-#ifdef NOT_USED
-static HashEntry *search_ent(TidList *tidlist);
+static const char *Ordered(PlanHint *plan, Query *parse, char *keyword, const char *str);
#endif
-PG_FUNCTION_INFO_V1(pg_add_hint);
-PG_FUNCTION_INFO_V1(pg_clear_hint);
+static void my_join_search_one_level(PlannerInfo *root, int level);
+static void make_rels_by_clause_joins(PlannerInfo *root, RelOptInfo *old_rel, ListCell *other_rels);
+static void make_rels_by_clauseless_joins(PlannerInfo *root, RelOptInfo *old_rel, ListCell *other_rels);
+static bool has_join_restriction(PlannerInfo *root, RelOptInfo *rel);
+static void set_plain_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte);
+
+
+/* GUC variables */
+static bool pg_hint_plan_enable = true;
+static bool pg_hint_plan_debug_print = false;
+static int pg_hint_plan_parse_message = INFO;
+
+static const struct config_enum_entry parse_message_level_options[] = {
+ {"debug", DEBUG2, true},
+ {"debug5", DEBUG5, false},
+ {"debug4", DEBUG4, false},
+ {"debug3", DEBUG3, false},
+ {"debug2", DEBUG2, false},
+ {"debug1", DEBUG1, false},
+ {"log", LOG, false},
+ {"info", INFO, false},
+ {"notice", NOTICE, false},
+ {"warning", WARNING, false},
+ {"error", ERROR, false},
+ /*
+ {"fatal", FATAL, true},
+ {"panic", PANIC, true},
+ */
+ {NULL, 0, false}
+};
+
+/* Saved hook values in case of unload */
+static planner_hook_type prev_planner_hook = NULL;
+static get_relation_info_hook_type prev_get_relation_info = NULL;
+static join_search_hook_type prev_join_search = NULL;
+
+/* フック関数をまたがって使用する情報を管理する */
+static PlanHint *global = NULL;
+
+static const HintParser parsers[] = {
+ {HINT_SEQSCAN, true, ParseScanMethod},
+ {HINT_INDEXSCAN, true, ParseIndexScanMethod},
+ {HINT_BITMAPSCAN, true, ParseIndexScanMethod},
+ {HINT_TIDSCAN, true, ParseScanMethod},
+ {HINT_NOSEQSCAN, true, ParseScanMethod},
+ {HINT_NOINDEXSCAN, true, ParseScanMethod},
+ {HINT_NOBITMAPSCAN, true, ParseScanMethod},
+ {HINT_NOTIDSCAN, true, ParseScanMethod},
+#if PG_VERSION_NUM >= 90200
+ {HINT_INDEXONLYSCAN, true, ParseIndexScanMethod},
+ {HINT_NOINDEXONLYSCAN, true, ParseIndexScanMethod},
+#endif
+ {HINT_SET, true, ParseSet},
+ {NULL, false, NULL},
+};
/*
* Module load callbacks
void
_PG_init(void)
{
- int i;
-
-#ifdef NOT_USED
- org_cost_hook = cost_hook;
- cost_hook = my_cost_hook;
-#endif
-
- for (i = 0 ; i < HASH_ENTRIES ; i++)
- hashent[i] = NULL;
+ /* Define custom GUC variables. */
+ DefineCustomBoolVariable("pg_hint_plan.enable",
+ "Instructions or hints to the planner using block comments.",
+ NULL,
+ &pg_hint_plan_enable,
+ true,
+ PGC_USERSET,
+ 0,
+ NULL,
+ NULL,
+ NULL);
+
+ DefineCustomBoolVariable("pg_hint_plan.debug_print",
+ "Logs each query's parse results of the hint.",
+ NULL,
+ &pg_hint_plan_debug_print,
+ false,
+ PGC_USERSET,
+ 0,
+ NULL,
+ NULL,
+ NULL);
+
+ DefineCustomEnumVariable("pg_hint_plan.parse_message",
+ "Messege level of the parse error.",
+ NULL,
+ &pg_hint_plan_parse_message,
+ INFO,
+ parse_message_level_options,
+ PGC_USERSET,
+ 0,
+ NULL,
+ NULL,
+ NULL);
+
+ /* Install hooks. */
+ prev_planner_hook = planner_hook;
+ planner_hook = pg_hint_plan_planner;
+ prev_get_relation_info = get_relation_info_hook;
+ get_relation_info_hook = pg_hint_plan_get_relation_info;
+ prev_join_search = join_search_hook;
+ join_search_hook = pg_hint_plan_join_search;
}
/*
void
_PG_fini(void)
{
- int i;
+ /* Uninstall hooks. */
+ planner_hook = prev_planner_hook;
+ get_relation_info_hook = prev_get_relation_info;
+ join_search_hook = prev_join_search;
+}
-#ifdef NOT_USED
- cost_hook = org_cost_hook;
-#endif
+static ScanHint *
+ScanHintCreate(void)
+{
+ ScanHint *hint;
- for (i = 0 ; i < HASH_ENTRIES ; i++)
- {
- free_hashent(hashent[i]);
- hashent[i] = NULL;
+ hint = palloc(sizeof(ScanHint));
+ hint->opt_str = NULL;
+ hint->relname = NULL;
+ hint->indexnames = NIL;
+ hint->enforce_mask = 0;
- }
+ return hint;
}
-#ifdef NOT_USED
-char *rels_str(PlannerInfo *root, Path *path)
+static void
+ScanHintDelete(ScanHint *hint)
+{
+ if (!hint)
+ return;
+
+ if (hint->relname)
+ pfree(hint->relname);
+ list_free_deep(hint->indexnames);
+ pfree(hint);
+}
+
+static JoinHint *
+JoinHintCreate(void)
{
- char buf[4096];
- int relid;
- int first = 1;
- Bitmapset *tmpbms;
+ JoinHint *hint;
- if (path->pathtype == T_Invalid) return strdup("");
+ hint = palloc(sizeof(JoinHint));
+ hint->opt_str = NULL;
+ hint->nrels = 0;
+ hint->relnames = NULL;
+ hint->enforce_mask = 0;
+ hint->joinrelids = NULL;
- tmpbms = bms_copy(path->parent->relids);
+ return hint;
+}
- buf[0] = 0;
- while ((relid = bms_first_member(tmpbms)) >= 0)
+static void
+JoinHintDelete(JoinHint *hint)
+{
+ if (!hint)
+ return;
+
+ if (hint->relnames)
{
- char idbuf[8];
- snprintf(idbuf, sizeof(idbuf), first ? "%d" : ", %d",
- root->simple_rte_array[relid]->relid);
- if (strlen(buf) + strlen(idbuf) < sizeof(buf))
- strcat(buf, idbuf);
- first = 0;
+ int i;
+
+ for (i = 0; i < hint->nrels; i++)
+ pfree(hint->relnames[i]);
+ pfree(hint->relnames);
}
+ bms_free(hint->joinrelids);
+ pfree(hint);
+}
+
+static SetHint *
+SetHintCreate(void)
+{
+ SetHint *hint;
+
+ hint = palloc(sizeof(SetHint));
+ hint->name = NULL;
+ hint->value = NULL;
- return strdup(buf);
+ return hint;
}
-#endif
-static int oidsortcmp(const void *a, const void *b)
+static void
+SetHintDelete(SetHint *hint)
{
- const Oid oida = *((const Oid *)a);
- const Oid oidb = *((const Oid *)b);
+ if (!hint)
+ return;
+
+ if (hint->name)
+ pfree(hint->name);
+ if (hint->value)
+ pfree(hint->value);
+ pfree(hint);
+}
- return oida - oidb;
+static PlanHint *
+PlanHintCreate(void)
+{
+ PlanHint *hint;
+
+ hint = palloc(sizeof(PlanHint));
+ hint->hint_str = NULL;
+ hint->nscan_hints = 0;
+ hint->max_scan_hints = 0;
+ hint->scan_hints = NULL;
+ hint->njoin_hints = 0;
+ hint->max_join_hints = 0;
+ hint->join_hints = NULL;
+ hint->nlevel = 0;
+ hint->join_hint_level = NULL;
+ hint->leading = NIL;
+ hint->context = superuser() ? PGC_SUSET : PGC_USERSET;
+ hint->set_hints = NIL;
+
+ return hint;
}
-#ifdef NOT_USED
-static TidList *maketidlist(PlannerInfo *root, Path *path1, Path *path2)
+static void
+PlanHintDelete(PlanHint *hint)
+{
+ ListCell *l;
+ int i;
+
+ if (!hint)
+ return;
+
+ if (hint->hint_str)
+ pfree(hint->hint_str);
+
+ for (i = 0; i < hint->nscan_hints; i++)
+ ScanHintDelete(hint->scan_hints[i]);
+ if (hint->scan_hints)
+ pfree(hint->scan_hints);
+
+ for (i = 0; i < hint->njoin_hints; i++)
+ JoinHintDelete(hint->join_hints[i]);
+ if (hint->join_hints)
+ pfree(hint->join_hints);
+
+ for (i = 2; i <= hint->nlevel; i++)
+ list_free(hint->join_hint_level[i]);
+ if (hint->join_hint_level)
+ pfree(hint->join_hint_level);
+
+ list_free_deep(hint->leading);
+
+ foreach(l, hint->set_hints)
+ SetHintDelete((SetHint *) lfirst(l));
+ list_free(hint->set_hints);
+
+ pfree(hint);
+}
+
+static bool
+PlanHintIsempty(PlanHint *hint)
{
- int relid;
- Path *paths[2] = {path1, path2};
- int i;
- int j = 0;
- int nrels = 0;
- TidList *ret = (TidList *)malloc(sizeof(TidList));
+ if (hint->nscan_hints == 0 &&
+ hint->njoin_hints == 0 &&
+ hint->leading == NIL &&
+ hint->set_hints == NIL)
+ return true;
- for (i = 0 ; i < 2 ; i++)
+ return false;
+}
+
+// TODO オブジェクト名のクォート処理を追加
+static void
+PlanHintDump(PlanHint *hint)
+{
+ StringInfoData buf;
+ ListCell *l;
+ int i;
+ bool is_first = true;
+
+ if (!hint)
{
- if (paths[i] != NULL)
- nrels += bms_num_members(paths[i]->parent->relids);
+ elog(INFO, "no hint");
+ return;
}
- ret->nrels = nrels;
- ret->oids = (Oid *)malloc(nrels * sizeof(Oid));
+ initStringInfo(&buf);
+ appendStringInfo(&buf, "/*\n");
+ for (i = 0; i < hint->nscan_hints; i++)
+ {
+ ScanHint *h = hint->scan_hints[i];
+ ListCell *n;
+ switch(h->enforce_mask)
+ {
+ case(ENABLE_SEQSCAN):
+ appendStringInfo(&buf, "%s(", HINT_SEQSCAN);
+ break;
+ case(ENABLE_INDEXSCAN):
+ appendStringInfo(&buf, "%s(", HINT_INDEXSCAN);
+ break;
+ case(ENABLE_BITMAPSCAN):
+ appendStringInfo(&buf, "%s(", HINT_BITMAPSCAN);
+ break;
+ case(ENABLE_TIDSCAN):
+ appendStringInfo(&buf, "%s(", HINT_TIDSCAN);
+ break;
+ case(ENABLE_INDEXSCAN | ENABLE_BITMAPSCAN | ENABLE_TIDSCAN):
+ appendStringInfo(&buf, "%s(", HINT_NOSEQSCAN);
+ break;
+ case(ENABLE_SEQSCAN | ENABLE_BITMAPSCAN | ENABLE_TIDSCAN):
+ appendStringInfo(&buf, "%s(", HINT_NOINDEXSCAN);
+ break;
+ case(ENABLE_SEQSCAN | ENABLE_INDEXSCAN | ENABLE_TIDSCAN):
+ appendStringInfo(&buf, "%s(", HINT_NOBITMAPSCAN);
+ break;
+ case(ENABLE_SEQSCAN | ENABLE_INDEXSCAN | ENABLE_BITMAPSCAN):
+ appendStringInfo(&buf, "%s(", HINT_NOTIDSCAN);
+ break;
+ default:
+ appendStringInfoString(&buf, "\?\?\?(");
+ break;
+ }
+ appendStringInfo(&buf, "%s", h->relname);
+ foreach(n, h->indexnames)
+ appendStringInfo(&buf, " %s", (char *) lfirst(n));
+ appendStringInfoString(&buf, ")\n");
+ }
- for (i = 0 ; i < 2 ; i++)
+ for (i = 0; i < hint->njoin_hints; i++)
{
- Bitmapset *tmpbms;
+ JoinHint *h = hint->join_hints[i];
+ int i;
+ switch(h->enforce_mask)
+ {
+ case(ENABLE_NESTLOOP):
+ appendStringInfo(&buf, "%s(", HINT_NESTLOOP);
+ break;
+ case(ENABLE_MERGEJOIN):
+ appendStringInfo(&buf, "%s(", HINT_MERGEJOIN);
+ break;
+ case(ENABLE_HASHJOIN):
+ appendStringInfo(&buf, "%s(", HINT_HASHJOIN);
+ break;
+ case(ENABLE_ALL_JOIN ^ ENABLE_NESTLOOP):
+ appendStringInfo(&buf, "%s(", HINT_NONESTLOOP);
+ break;
+ case(ENABLE_ALL_JOIN ^ ENABLE_MERGEJOIN):
+ appendStringInfo(&buf, "%s(", HINT_NOMERGEJOIN);
+ break;
+ case(ENABLE_ALL_JOIN ^ ENABLE_HASHJOIN):
+ appendStringInfo(&buf, "%s(", HINT_NOHASHJOIN);
+ break;
+ case(ENABLE_ALL_JOIN):
+ continue;
+ default:
+ appendStringInfoString(&buf, "\?\?\?(");
+ break;
+ }
+ appendStringInfo(&buf, "%s", h->relnames[0]);
+ for (i = 1; i < h->nrels; i++)
+ appendStringInfo(&buf, " %s", h->relnames[i]);
+ appendStringInfoString(&buf, ")\n");
+ }
- if (paths[i] == NULL) continue;
+ foreach(l, hint->set_hints)
+ {
+ SetHint *h = (SetHint *) lfirst(l);
+ appendStringInfo(&buf, "%s(%s %s)\n", HINT_SET, h->name, h->value);
+ }
+
+ foreach(l, hint->leading)
+ {
+ if (is_first)
+ {
+ appendStringInfo(&buf, "%s(%s", HINT_LEADING, (char *)lfirst(l));
+ is_first = false;
+ }
+ else
+ appendStringInfo(&buf, " %s", (char *)lfirst(l));
+ }
+ if (!is_first)
+ appendStringInfoString(&buf, ")\n");
+
+ appendStringInfoString(&buf, "*/");
+
+ elog(INFO, "%s", buf.data);
- tmpbms= bms_copy(paths[i]->parent->relids);
+ pfree(buf.data);
+}
+
+static int
+RelnameCmp(const void *a, const void *b)
+{
+ const char *relnamea = *((const char **) a);
+ const char *relnameb = *((const char **) b);
+
+ return strcmp(relnamea, relnameb);
+}
+
+static int
+ScanHintCmp(const void *a, const void *b, bool order)
+{
+ const ScanHint *hinta = *((const ScanHint **) a);
+ const ScanHint *hintb = *((const ScanHint **) b);
+ int result;
- while ((relid = bms_first_member(tmpbms)) >= 0)
- ret->oids[j++] = root->simple_rte_array[relid]->relid;
+ if ((result = strcmp(hinta->relname, hintb->relname)) != 0)
+ return result;
+
+ /* ヒント句で指定した順を返す */
+ if (order)
+ return hinta->opt_str - hintb->opt_str;
+ else
+ return 0;
+}
+
+static int
+ScanHintCmpIsOrder(const void *a, const void *b)
+{
+ return ScanHintCmp(a, b, true);
+}
+
+static int
+JoinHintCmp(const void *a, const void *b, bool order)
+{
+ const JoinHint *hinta = *((const JoinHint **) a);
+ const JoinHint *hintb = *((const JoinHint **) b);
+
+ if (hinta->nrels == hintb->nrels)
+ {
+ int i;
+ for (i = 0; i < hinta->nrels; i++)
+ {
+ int result;
+ if ((result = strcmp(hinta->relnames[i], hintb->relnames[i])) != 0)
+ return result;
+ }
+
+ /* ヒント句で指定した順を返す */
+ if (order)
+ return hinta->opt_str - hintb->opt_str;
+ else
+ return 0;
}
- if (nrels > 1)
- qsort(ret->oids, nrels, sizeof(Oid), oidsortcmp);
+ return hinta->nrels - hintb->nrels;
+}
- return ret;
+static int
+JoinHintCmpIsOrder(const void *a, const void *b)
+{
+ return JoinHintCmp(a, b, true);
}
-static void free_tidlist(TidList *tidlist)
+static int
+set_config_options(List *options, GucContext context)
{
- if (tidlist)
+ ListCell *l;
+ int save_nestlevel;
+ int result = 1;
+
+ save_nestlevel = NewGUCNestLevel();
+
+ foreach(l, options)
{
- if (tidlist->oids)
- free(tidlist->oids);
- free(tidlist);
+ SetHint *hint = (SetHint *) lfirst(l);
+
+ if (result > 0)
+ result = set_config_option(hint->name, hint->value, context,
+ PGC_S_SESSION, GUC_ACTION_SAVE, true,
+ pg_hint_plan_parse_message);
}
+
+ return save_nestlevel;
}
-int n = 0;
-static void dump_rels(char *label, PlannerInfo *root, Path *path, bool found, bool enabled)
+#define SET_CONFIG_OPTION(name, enforce_mask, type_bits) \
+ set_config_option((name), \
+ ((enforce_mask) & (type_bits)) ? "true" : "false", \
+ context, PGC_S_SESSION, GUC_ACTION_SAVE, true, ERROR)
+
+static void
+set_join_config_options(unsigned char enforce_mask, GucContext context)
+{
+ SET_CONFIG_OPTION("enable_nestloop", enforce_mask, ENABLE_NESTLOOP);
+ SET_CONFIG_OPTION("enable_mergejoin", enforce_mask, ENABLE_MERGEJOIN);
+ SET_CONFIG_OPTION("enable_hashjoin", enforce_mask, ENABLE_HASHJOIN);
+}
+
+static void
+set_scan_config_options(unsigned char enforce_mask, GucContext context)
+{
+ SET_CONFIG_OPTION("enable_seqscan", enforce_mask, ENABLE_SEQSCAN);
+ SET_CONFIG_OPTION("enable_indexscan", enforce_mask, ENABLE_INDEXSCAN);
+ SET_CONFIG_OPTION("enable_bitmapscan", enforce_mask, ENABLE_BITMAPSCAN);
+ SET_CONFIG_OPTION("enable_tidscan", enforce_mask, ENABLE_TIDSCAN);
+#if PG_VERSION_NUM >= 90200
+ SET_CONFIG_OPTION("enable_indexonlyscan", enforce_mask, ENABLE_INDEXSCAN);
+#endif
+}
+
+/*
+ * parse functions
+ */
+
+static const char *
+parse_keyword(const char *str, StringInfo buf)
{
- char *relsstr;
+ skip_space(str);
- if (!print_log) return;
- relsstr = rels_str(root, path);
- ereport(LOG, (errmsg_internal("%04d: %s for relation %s (%s, %s)\n",
- n++, label, relsstr,
- found ? "found" : "not found",
- enabled ? "enabled" : "disabled")));
- free(relsstr);
+ while (!isspace(*str) && *str != '(' && *str != '\0')
+ appendStringInfoChar(buf, *str++);
+
+ return str;
}
-void dump_joinrels(char *label, PlannerInfo *root, Path *inpath, Path *outpath,
- bool found, bool enabled)
+static const char *
+skip_opened_parenthesis(const char *str)
{
- char *irelstr, *orelstr;
+ skip_space(str);
+
+ if (*str != '(')
+ {
+ parse_ereport(str, ("Opened parenthesis is necessary."));
+ return NULL;
+ }
- if (!print_log) return;
- irelstr = rels_str(root, inpath);
- orelstr = rels_str(root, outpath);
+ str++;
- ereport(LOG, (errmsg_internal("%04d: %s for relation ((%s),(%s)) (%s, %s)\n",
- n++, label, irelstr, orelstr,
- found ? "found" : "not found",
- enabled ? "enabled" : "disabled")));
- free(irelstr);
- free(orelstr);
+ return str;
}
+static const char *
+skip_closed_parenthesis(const char *str)
+{
+ skip_space(str);
+
+ if (*str != ')')
+ {
+ parse_ereport(str, ("Closed parenthesis is necessary."));
+ return NULL;
+ }
+
+ str++;
+
+ return str;
+}
-bool my_cost_hook(CostHookType type, PlannerInfo *root, Path *path1, Path *path2)
+static const char *
+parse_quote_value(const char *str, char **word, char *value_type)
{
- TidList *tidlist;
- HashEntry *ent;
- bool ret = false;
+ StringInfoData buf;
+ bool in_quote;
- if (!tweak_enabled)
+ skip_space(str);
+
+ initStringInfo(&buf);
+ if (*str == '"')
+ {
+ str++;
+ in_quote = true;
+ }
+ else
{
- switch (type)
+ /*
+ * 1文字目以降の制限の適用
+ */
+ if (!isalpha(*str) && *str != '_')
{
- case COSTHOOK_seqscan:
- return enable_seqscan;
- case COSTHOOK_indexscan:
- return enable_indexscan;
- case COSTHOOK_bitmapscan:
- return enable_bitmapscan;
- case COSTHOOK_tidscan:
- return enable_tidscan;
- case COSTHOOK_nestloop:
- return enable_nestloop;
- case COSTHOOK_mergejoin:
- return enable_mergejoin;
- case COSTHOOK_hashjoin:
- return enable_hashjoin;
- default:
- ereport(LOG, (errmsg_internal("Unknown cost type")));
+ pfree(buf.data);
+ parse_ereport(str, ("Need for %s to be quoted.", value_type));
+ return NULL;
+ }
+
+ in_quote = false;
+ appendStringInfoCharMacro(&buf, *str++);
+ }
+
+ while (true)
+ {
+ if (in_quote)
+ {
+ if (*str == '\0')
+ {
+ pfree(buf.data);
+ parse_ereport(str, ("Unterminated quoted %s.", value_type));
+ return NULL;
+ }
+
+ /*
+ * エスケープ対象をスキップする。
+ * TODO エスケープ対象の仕様にあわせた処理を行う。
+ */
+ if(*str == '"')
+ {
+ str++;
+ if (*str != '"')
+ break;
+ }
+ }
+ else
+ {
+ /*
+ * 2文字目以降の制限の適用
+ */
+ if (!isalnum(*str) && *str != '_' && *str != '$')
break;
}
+
+ appendStringInfoCharMacro(&buf, *str++);
+ }
+
+ if (buf.len == 0)
+ {
+ pfree(buf.data);
+ parse_ereport(str, ("%s is necessary.", value_type));
+ return NULL;
}
- switch (type)
- {
- case COSTHOOK_seqscan:
- tidlist = maketidlist(root, path1, path2);
- ent = search_ent(tidlist);
- free_tidlist(tidlist);
- ret = (ent ? (ent->enforce_mask & ENABLE_SEQSCAN) :
- enable_seqscan);
- dump_rels("cost_seqscan", root, path1, ent != NULL, ret);
- return ret;
- case COSTHOOK_indexscan:
- tidlist = maketidlist(root, path1, path2);
- ent = search_ent(tidlist);
- free_tidlist(tidlist);
- ret = (ent ? (ent->enforce_mask & ENABLE_INDEXSCAN) :
- enable_indexscan);
- dump_rels("cost_indexscan", root, path1, ent != NULL, ret);
- return ret;
- case COSTHOOK_bitmapscan:
- if (path1->pathtype != T_BitmapHeapScan)
+
+ *word = buf.data;
+
+ return str;
+}
+
+static const char *
+skip_option_delimiter(const char *str)
+{
+ const char *p = str;
+
+ skip_space(str);
+
+ if (str == p)
+ {
+ parse_ereport(str, ("Must be specified space."));
+ return NULL;
+ }
+
+ return str;
+}
+
+static bool
+parse_hints(PlanHint *plan, Query *parse, const char *str)
+{
+ StringInfoData buf;
+ char *head;
+
+ initStringInfo(&buf);
+ while (*str != '\0')
+ {
+ const HintParser *parser;
+
+ /* in error message, we output the comment including the keyword. */
+ head = (char *) str;
+
+ /* parse only the keyword of the hint. */
+ resetStringInfo(&buf);
+ str = parse_keyword(str, &buf);
+
+ for (parser = parsers; parser->keyword != NULL; parser++)
+ {
+ char *keyword = parser->keyword;
+
+ if (strcasecmp(buf.data, keyword) != 0)
+ continue;
+
+ if (parser->have_paren)
{
- ent = NULL;
- ret = enable_bitmapscan;
+ /* parser of each hint does parse in a parenthesis. */
+ if ((str = skip_opened_parenthesis(str)) == NULL ||
+ (str = parser->hint_parser(plan, parse, keyword, str)) == NULL ||
+ (str = skip_closed_parenthesis(str)) == NULL)
+ {
+ pfree(buf.data);
+ return false;
+ }
}
else
{
- tidlist = maketidlist(root, path1, path2);
- ent = search_ent(tidlist);
- free_tidlist(tidlist);
- ret = (ent ? (ent->enforce_mask & ENABLE_BITMAPSCAN) :
- enable_bitmapscan);
+ if ((str = parser->hint_parser(plan, parse, keyword, str)) == NULL)
+ {
+ pfree(buf.data);
+ return false;
+ }
+
+ /*
+ * 直前のヒントに括弧の指定がなければ次のヒントの間に空白が必要
+ */
+ if (!isspace(*str) && *str == '\0')
+ parse_ereport(str, ("Delimiter of the hint is necessary."));
}
- dump_rels("cost_bitmapscan", root, path1, ent != NULL, ret);
-
- return ret;
- case COSTHOOK_tidscan:
- tidlist = maketidlist(root, path1, path2);
- ent = search_ent(tidlist);
- free_tidlist(tidlist);
- ret = (ent ? (ent->enforce_mask & ENABLE_TIDSCAN) :
- enable_tidscan);
- dump_rels("cost_tidscan", root, path1, ent != NULL, ret);
- return ret;
- case COSTHOOK_nestloop:
- tidlist = maketidlist(root, path1, path2);
- ent = search_ent(tidlist);
- free_tidlist(tidlist);
- ret = (ent ? (ent->enforce_mask & ENABLE_NESTLOOP) :
- enable_nestloop);
- dump_joinrels("cost_nestloop", root, path1, path2,
- ent != NULL, ret);
- return ret;
- case COSTHOOK_mergejoin:
- tidlist = maketidlist(root, path1, path2);
- ent = search_ent(tidlist);
- free_tidlist(tidlist);
- ret = (ent ? (ent->enforce_mask & ENABLE_MERGEJOIN) :
- enable_mergejoin);
- dump_joinrels("cost_mergejoin", root, path1, path2,
- ent != NULL, ret);
- return ret;
- case COSTHOOK_hashjoin:
- tidlist = maketidlist(root, path1, path2);
- ent = search_ent(tidlist);
- free_tidlist(tidlist);
- ret = (ent ? (ent->enforce_mask & ENABLE_HASHJOIN) :
- enable_hashjoin);
- dump_joinrels("cost_hashjoin", root, path1, path2,
- ent != NULL, ret);
- return ret;
- default:
- ereport(LOG, (errmsg_internal("Unknown cost type")));
+
+ skip_space(str);
+
break;
+ }
+
+ if (parser->keyword == NULL)
+ {
+ parse_ereport(head, ("Keyword \"%s\" does not exist.", buf.data));
+ pfree(buf.data);
+ return false;
+ }
}
-
+
+ pfree(buf.data);
+
return true;
}
-#endif
-static void free_hashent(HashEntry *head)
+/*
+ * Do basic parsing of the query head comment.
+ */
+static PlanHint *
+parse_head_comment(Query *parse)
{
- HashEntry *next = head;
+ const char *p;
+ char *head;
+ char *tail;
+ int len;
+ int i;
+ PlanHint *plan;
+
+ /* get client-supplied query string. */
+ p = debug_query_string;
+ if (p == NULL)
+ return NULL;
+
+
+ /* extract query head comment. */
+ len = strlen(HINT_START);
+ skip_space(p);
+ if (strncmp(p, HINT_START, len))
+ return NULL;
- while (next)
+ p += len;
+ skip_space(p);
+
+ if ((tail = strstr(p, HINT_END)) == NULL)
+ elog(ERROR, "unterminated /* comment at or near \"%s\"",
+ debug_query_string);
+
+ /* 入れ子にしたブロックコメントはサポートしない */
+ if ((head = strstr(p, HINT_START)) != NULL && head < tail)
+ parse_ereport(head, ("block comments nest doesn't supported"));
+
+ /* ヒント句部分を切り出す */
+ len = tail - p;
+ head = palloc(len + 1);
+ memcpy(head, p, len);
+ head[len] = '\0';
+ p = head;
+
+ plan = PlanHintCreate();
+ plan->hint_str = head;
+
+ /* parse each hint. */
+ if (!parse_hints(plan, parse, p))
+ return plan;
+
+ /* 重複したScan条件をを除外する */
+ qsort(plan->scan_hints, plan->nscan_hints, sizeof(ScanHint *), ScanHintCmpIsOrder);
+ for (i = 0; i < plan->nscan_hints - 1;)
{
- HashEntry *last = next;
- if (next->tidlist.oids != NULL) free(next->tidlist.oids);
- next = next->next;
- free(last);
+ int result = ScanHintCmp(plan->scan_hints + i,
+ plan->scan_hints + i + 1, false);
+ if (result != 0)
+ i++;
+ else
+ {
+ /* 後で指定したヒントを有効にする */
+ plan->nscan_hints--;
+ memmove(plan->scan_hints + i, plan->scan_hints + i + 1,
+ sizeof(ScanHint *) * (plan->nscan_hints - i));
+ }
}
+
+ /* 重複したJoin条件をを除外する */
+ qsort(plan->join_hints, plan->njoin_hints, sizeof(JoinHint *), JoinHintCmpIsOrder);
+ for (i = 0; i < plan->njoin_hints - 1;)
+ {
+ int result = JoinHintCmp(plan->join_hints + i,
+ plan->join_hints + i + 1, false);
+ if (result != 0)
+ i++;
+ else
+ {
+ /* 後で指定したヒントを有効にする */
+ plan->njoin_hints--;
+ memmove(plan->join_hints + i, plan->join_hints + i + 1,
+ sizeof(JoinHint *) * (plan->njoin_hints - i));
+ }
+ }
+
+ return plan;
}
-static HashEntry *parse_tidlist(char **str)
+static const char *
+parse_scan_method(PlanHint *plan, Query *parse, char *keyword, const char *str)
{
- char tidstr[8];
- char *p0;
- Oid tid[20]; /* ^^; */
- int ntids = 0;
- int i, len;
- HashEntry *ret;
+ ScanHint *hint;
+
+ hint = ScanHintCreate();
+ hint->opt_str = str;
- while (isdigit(**str) && ntids < 20)
+ if ((str = parse_quote_value(str, &hint->relname, "ralation name")) == NULL)
{
- p0 = *str;
- while (isdigit(**str)) (*str)++;
- len = *str - p0;
- if (len >= 8) return NULL;
- strncpy(tidstr, p0, len);
- tidstr[len] = 0;
-
- /* Tis 0 is valid? I don't know :-p */
- if ((tid[ntids++] = atoi(tidstr)) == 0) return NULL;
+ ScanHintDelete(hint);
+ return NULL;
+ }
+
+ if (strcasecmp(keyword, HINT_SEQSCAN) == 0)
+ hint->enforce_mask = ENABLE_SEQSCAN;
+ else if (strcasecmp(keyword, HINT_INDEXSCAN) == 0)
+ hint->enforce_mask = ENABLE_INDEXSCAN;
+ else if (strcasecmp(keyword, HINT_BITMAPSCAN) == 0)
+ hint->enforce_mask = ENABLE_BITMAPSCAN;
+ else if (strcasecmp(keyword, HINT_TIDSCAN) == 0)
+ hint->enforce_mask = ENABLE_TIDSCAN;
+ else if (strcasecmp(keyword, HINT_NOSEQSCAN) == 0)
+ hint->enforce_mask = ENABLE_ALL_SCAN ^ ENABLE_SEQSCAN;
+ else if (strcasecmp(keyword, HINT_NOINDEXSCAN) == 0)
+ hint->enforce_mask = ENABLE_ALL_SCAN ^ ENABLE_INDEXSCAN;
+ else if (strcasecmp(keyword, HINT_NOBITMAPSCAN) == 0)
+ hint->enforce_mask = ENABLE_ALL_SCAN ^ ENABLE_BITMAPSCAN;
+ else if (strcasecmp(keyword, HINT_NOTIDSCAN) == 0)
+ hint->enforce_mask = ENABLE_ALL_SCAN ^ ENABLE_TIDSCAN;
+ else
+ {
+ elog(ERROR, "unrecognized hint keyword \"%s\"", keyword);
+ return NULL;
+ }
- if (**str == ',') (*str)++;
+ if (plan->nscan_hints == 0)
+ {
+ plan->max_scan_hints = HINT_ARRAY_DEFAULT_INITSIZE;
+ plan->scan_hints = palloc(sizeof(JoinHint *) * plan->max_scan_hints);
+ }
+ else if (plan->nscan_hints == plan->max_scan_hints)
+ {
+ plan->max_scan_hints *= 2;
+ plan->scan_hints = repalloc(plan->scan_hints,
+ sizeof(JoinHint *) * plan->max_scan_hints);
}
- if (ntids > 1)
- qsort(tid, ntids, sizeof(Oid), oidsortcmp);
- ret = (HashEntry*)malloc(sizeof(HashEntry));
- ret->next = NULL;
- ret->enforce_mask = 0;
- ret->tidlist.nrels = ntids;
- ret->tidlist.oids = (Oid *)malloc(ntids * sizeof(Oid));
- for (i = 0 ; i < ntids ; i++)
- ret->tidlist.oids[i] = tid[i];
- return ret;
+ plan->scan_hints[plan->nscan_hints] = hint;
+ plan->nscan_hints++;
+
+ return str;
}
-static int parse_phrase(HashEntry **head, char **str)
+static const char *
+ParseScanMethod(PlanHint *plan, Query *parse, char *keyword, const char *str)
{
- char *cmds[] = {"seq", "index", "nest", "merge", "hash", NULL};
- unsigned char masks[] = {ENABLE_SEQSCAN, ENABLE_INDEXSCAN|ENABLE_BITMAPSCAN,
- ENABLE_NESTLOOP, ENABLE_MERGEJOIN, ENABLE_HASHJOIN};
- char req[12];
- int cmd;
- HashEntry *ent = NULL;
- char *p0;
- int len;
+ ScanHint *hint;
- p0 = *str;
- while (isalpha(**str)) (*str)++;
- len = *str - p0;
- if (**str != '(' || len >= 12) return 0;
- strncpy(req, p0, len);
- req[len] = 0;
- for (cmd = 0 ; cmds[cmd] && strcmp(cmds[cmd], req) ; cmd++);
- if (cmds[cmd] == NULL) return 0;
- (*str)++;
- if ((ent = parse_tidlist(str)) == NULL) return 0;
- if (*(*str)++ != ')') return 0;
- if (**str != 0 && **str != ';') return 0;
- if (**str == ';') (*str)++;
- ent->enforce_mask = masks[cmd];
- ent->next = NULL;
- *head = ent;
+ if ((str = parse_scan_method(plan, parse, keyword, str)) == NULL)
+ return NULL;
+
+ hint = plan->scan_hints[plan->nscan_hints - 1];
- return 1;
+ skip_space(str);
+ if (*str != ')')
+ {
+ parse_ereport(str, ("Closed parenthesis is necessary."));
+ plan->nscan_hints--;
+ ScanHintDelete(hint);
+ return NULL;
+ }
+
+ return str;
}
+static const char *
+ParseIndexScanMethod(PlanHint *plan, Query *parse, char *keyword, const char *str)
+{
+ char *indexname;
+ ScanHint *hint;
+
+ if ((str = parse_scan_method(plan, parse, keyword, str)) == NULL)
+ return NULL;
+
+ hint = plan->scan_hints[plan->nscan_hints - 1];
+
+ /* インデックス参照をパースする。 */
+ while (true)
+ {
+ // TODO 直前のオブジェクト名がクウォート処理されていた場合の処理を実装
+ skip_space(str);
+ if (*str == ')')
+ break;
+
+ if ((str = parse_quote_value(str, &indexname, "index name")) == NULL)
+ {
+ plan->nscan_hints--;
+ ScanHintDelete(hint);
+ return NULL;
+ }
+
+ hint->indexnames = lappend(hint->indexnames, indexname);
+ }
+
+ return str;
+}
-static HashEntry* parse_top(char* str)
+static const char *
+ParseSet(PlanHint *plan, Query *parse, char *keyword, const char *str)
{
- HashEntry *head = NULL;
- HashEntry *ent = NULL;
+ SetHint *hint;
+
+ hint = SetHintCreate();
+
+ if ((str = parse_quote_value(str, &hint->name, "parameter name")) == NULL ||
+ (str = skip_option_delimiter(str)) == NULL ||
+ (str = parse_quote_value(str, &hint->value, "parameter value")) == NULL)
+ {
+ SetHintDelete(hint);
+ return NULL;
+ }
- if (!parse_phrase(&head, &str))
+ skip_space(str);
+ if (*str != ')')
{
- free_hashent(head);
+ parse_ereport(str, ("Closed parenthesis is necessary."));
+ SetHintDelete(hint);
return NULL;
}
- ent = head;
+ plan->set_hints = lappend(plan->set_hints, hint);
+
+ return str;
+}
+
+#ifdef NOT_USED
+/*
+ * Oracle の ORDERD ヒントの実装
+ */
+static const char *
+Ordered(PlanHint *plan, Query *parse, char *keyword, const char *str)
+{
+ SetHint *hint;
+
+ hint = SetHintCreate();
+ hint->name = pstrdup("join_collapse_limit");
+ hint->value = pstrdup("1");
+ plan->set_hints = lappend(plan->set_hints, hint);
+
+ return str;
+}
+#endif
+
+static PlannedStmt *
+pg_hint_plan_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
+{
+ int save_nestlevel;
+ PlannedStmt *result;
+
+ /*
+ * hintが指定されない、または空のhintを指定された場合は通常のparser処理をお
+ * こなう。
+ * 他のフック関数で実行されるhint処理をスキップするために、global 変数をNULL
+ * に設定しておく。
+ */
+ if (!pg_hint_plan_enable ||
+ (global = parse_head_comment(parse)) == NULL ||
+ PlanHintIsempty(global))
+ {
+ PlanHintDelete(global);
+ global = NULL;
+
+ if (prev_planner_hook)
+ return (*prev_planner_hook) (parse, cursorOptions, boundParams);
+ else
+ return standard_planner(parse, cursorOptions, boundParams);
+ }
+
+ /* Set hint で指定されたGUCパラメータを設定する */
+ save_nestlevel = set_config_options(global->set_hints, global->context);
- while (*str)
+ if (global->leading != NIL)
+ set_join_config_options(0, global->context);
+
+ /*
+ * TODO ビュー定義で指定したテーブル数が1つの場合にもこのタイミングでGUCを変更する必
+ * 要がある。
+ */
+ if (list_length(parse->rtable) == 1 &&
+ ((RangeTblEntry *) linitial(parse->rtable))->rtekind == RTE_RELATION)
{
- if (!parse_phrase(&ent->next, &str))
+ int i;
+ RangeTblEntry *rte = linitial(parse->rtable);
+
+ for (i = 0; i < global->nscan_hints; i++)
{
- free_hashent(head);
- return NULL;
+ ScanHint *hint = global->scan_hints[i];
+
+ if (strcmp(hint->relname, rte->eref->aliasname) != 0)
+ parse_ereport(hint->opt_str, ("Relation \"%s\" does not exist.", hint->relname));
+
+ set_scan_config_options(hint->enforce_mask, global->context);
}
- ent = ent->next;
}
- return head;
+ if (prev_planner_hook)
+ result = (*prev_planner_hook) (parse, cursorOptions, boundParams);
+ else
+ result = standard_planner(parse, cursorOptions, boundParams);
+
+ /*
+ * Restore the GUC variables we set above.
+ */
+ AtEOXact_GUC(true, save_nestlevel);
+
+ if (pg_hint_plan_debug_print)
+ {
+ PlanHintDump(global);
+ //elog_node_display(INFO, "rtable", parse->rtable, true);
+ }
+
+ PlanHintDelete(global);
+ global = NULL;
+
+ return result;
}
-static bool ent_matches(TidList *key, HashEntry *ent2)
+/*
+ * aliasnameと一致するSCANヒントを探す
+ */
+static ScanHint *
+find_scan_hint(RangeTblEntry *rte)
{
- int i;
+ int i;
- if (key->nrels != ent2->tidlist.nrels)
- return 0;
+ for (i = 0; i < global->nscan_hints; i++)
+ {
+ ScanHint *hint = global->scan_hints[i];
- for (i = 0 ; i < key->nrels ; i++)
- if (key->oids[i] != ent2->tidlist.oids[i])
- return 0;
+ if (strcmp(rte->eref->aliasname, hint->relname) == 0)
+ return hint;
+ }
- return 1;
+ return NULL;
}
-static unsigned int calc_hash(TidList *tidlist)
+static void
+pg_hint_plan_get_relation_info(PlannerInfo *root, Oid relationObjectId,
+ bool inhparent, RelOptInfo *rel)
{
- unsigned int hash = 0;
- int i = 0;
-
- for (i = 0 ; i < tidlist->nrels ; i++)
+ ScanHint *hint;
+ ListCell *cell;
+ ListCell *prev;
+ ListCell *next;
+
+ if (prev_get_relation_info)
+ (*prev_get_relation_info) (root, relationObjectId, inhparent, rel);
+
+ /* 有効なヒントが指定されなかった場合は処理をスキップする。 */
+ if (!global)
+ return;
+
+ if (rel->reloptkind != RELOPT_BASEREL)
+ return;
+
+ if ((hint = find_scan_hint(root->simple_rte_array[rel->relid])) == NULL)
+ return;
+
+ /* インデックスを全て削除し、スキャンに使えなくする */
+ if (hint->enforce_mask == ENABLE_SEQSCAN)
{
- int j = 0;
- for (j = 0 ; j < sizeof(Oid) ; j++)
- hash = hash * 2 + ((tidlist->oids[i] >> (j * 8)) & 0xff);
+ list_free_deep(rel->indexlist);
+ rel->indexlist = NIL;
+
+ return;
}
- return hash % HASH_ENTRIES;
-;
+ /* 後でパスを作り直すため、ここではなにもしない */
+ if (hint->indexnames == NULL)
+ return;
+
+ /* 指定されたインデックスのみをのこす */
+ prev = NULL;
+ for (cell = list_head(rel->indexlist); cell; cell = next)
+ {
+ IndexOptInfo *info = (IndexOptInfo *) lfirst(cell);
+ char *indexname = get_rel_name(info->indexoid);
+ ListCell *l;
+ bool use_index = false;
+
+ next = lnext(cell);
+
+ foreach(l, hint->indexnames)
+ {
+ if (strcmp(indexname, lfirst(l)) == 0)
+ {
+ use_index = true;
+ break;
+ }
+ }
+
+ if (!use_index)
+ rel->indexlist = list_delete_cell(rel->indexlist, cell, prev);
+ else
+ prev = cell;
+
+ pfree(indexname);
+ }
}
-#ifdef NOT_USED
-static HashEntry *search_ent(TidList *tidlist)
+static Index
+scan_relid_aliasname(PlannerInfo *root, char *aliasname, bool check_ambiguous, const char *str)
{
- HashEntry *ent;
- if (tidlist == NULL) return NULL;
+ // TODO refnameRangeTblEntry を参考
+ int i;
+ Index find = 0;
- ent = hashent[calc_hash(tidlist)];
- while(ent)
+ for (i = 1; i < root->simple_rel_array_size; i++)
{
- if (ent_matches(tidlist, ent))
- return ent;
- ent = ent->next;
+ if (root->simple_rel_array[i] == NULL)
+ continue;
+
+ Assert(i == root->simple_rel_array[i]->relid);
+
+ if (strcmp(aliasname, root->simple_rte_array[i]->eref->aliasname) != 0)
+ continue;
+
+ if (!check_ambiguous)
+ return i;
+
+ if (find)
+ parse_ereport(str, ("relation name \"%s\" is ambiguous", aliasname));
+
+ find = i;
+ }
+
+ return find;
+}
+
+/*
+ * relidビットマスクと一致するヒントを探す
+ */
+static JoinHint *
+scan_join_hint(Relids joinrelids)
+{
+ List *join_hint;
+ ListCell *l;
+
+ join_hint = global->join_hint_level[bms_num_members(joinrelids)];
+ foreach(l, join_hint)
+ {
+ JoinHint *hint = (JoinHint *) lfirst(l);
+ if (bms_equal(joinrelids, hint->joinrelids))
+ return hint;
}
return NULL;
}
-#endif
-Datum
-pg_add_hint(PG_FUNCTION_ARGS)
+/*
+ * ヒントを使用しやすい構造に変換する。
+ */
+static void
+rebuild_join_hints(PlanHint *plan, PlannerInfo *root, int level, List *initial_rels)
{
- HashEntry *ret = NULL;
- char *str = NULL;
- int i = 0;
+ int i;
+ ListCell *l;
+ Relids joinrelids;
+ int njoinrels;
+
+ plan->nlevel = root->simple_rel_array_size - 1;
+ plan->join_hint_level = palloc0(sizeof(List *) * (root->simple_rel_array_size));
+ for (i = 0; i < plan->njoin_hints; i++)
+ {
+ JoinHint *hint = plan->join_hints[i];
+ int j;
+ Index relid = 0;
- if (PG_NARGS() < 1)
- ereport(ERROR, (errmsg_internal("No argument")));
+ for (j = 0; j < hint->nrels; j++)
+ {
+ char *relname = hint->relnames[j];
- str = text_to_cstring(PG_GETARG_TEXT_PP(0));
+ relid = scan_relid_aliasname(root, relname, true, hint->opt_str);
+ if (relid == 0)
+ {
+ parse_ereport(hint->opt_str, ("Relation \"%s\" does not exist.", relname));
+ break;
+ }
+
+ hint->joinrelids = bms_add_member(hint->joinrelids, relid);
+ }
- ret = parse_top(str);
+ if (relid == 0)
+ continue;
- if (ret == NULL)
- ereport(ERROR, (errmsg_internal("Parse Error")));
+ plan->join_hint_level[hint->nrels] =
+ lappend(plan->join_hint_level[hint->nrels], hint);
+ }
- while (ret)
+ /* Leading hint は、全ての join 方式が有効な hint として登録する */
+ joinrelids = NULL;
+ njoinrels = 0;
+ foreach(l, plan->leading)
{
- HashEntry *etmp = NULL;
- HashEntry *next = NULL;
- int hash = calc_hash(&ret->tidlist);
- while (hashent[hash] && ent_matches(&ret->tidlist, hashent[hash]))
+ char *relname = (char *)lfirst(l);
+ JoinHint *hint;
+
+ i = scan_relid_aliasname(root, relname, true, plan->hint_str);
+ if (i == 0)
{
- etmp = hashent[hash]->next;
- hashent[hash]->next = NULL;
- free_hashent(hashent[hash]);
- hashent[hash] = etmp;
+ parse_ereport(plan->hint_str, ("Relation \"%s\" does not exist.", relname));
+ list_free_deep(plan->leading);
+ plan->leading = NIL;
+ break;
+ }
+ joinrelids = bms_add_member(joinrelids, i);
+ njoinrels++;
+
+ if (njoinrels < 2)
+ continue;
+
+ if (njoinrels > plan->nlevel)
+ {
+ parse_ereport(plan->hint_str, ("In %s hint, specified relation name %d or less.", HINT_LEADING, plan->nlevel));
+ break;
}
- etmp = hashent[hash];
- while (etmp && etmp->next)
+
+ /* Leading で指定した組み合わせ以外の join hint を削除する */
+ hint = scan_join_hint(joinrelids);
+ list_free(plan->join_hint_level[njoinrels]);
+ if (hint)
+ plan->join_hint_level[njoinrels] = lappend(NIL, hint);
+ else
{
- if (ent_matches(&ret->tidlist, etmp->next))
+ hint = JoinHintCreate();
+ hint->nrels = njoinrels;
+ hint->enforce_mask = ENABLE_ALL_JOIN;
+ hint->joinrelids = bms_copy(joinrelids);
+ plan->join_hint_level[njoinrels] = lappend(NIL, hint);
+
+ if (plan->njoin_hints == 0)
{
- HashEntry *etmp2 = etmp->next->next;
- etmp->next->next = NULL;
- free_hashent(etmp->next);
- etmp->next = etmp2;
- } else
- etmp = etmp->next;
- }
+ plan->max_join_hints = HINT_ARRAY_DEFAULT_INITSIZE;
+ plan->join_hints = palloc(sizeof(JoinHint *) * plan->max_join_hints);
+ }
+ else if (plan->njoin_hints == plan->max_join_hints)
+ {
+ plan->max_join_hints *= 2;
+ plan->join_hints = repalloc(plan->join_hints,
+ sizeof(JoinHint *) * plan->max_join_hints);
+ }
- i++;
- next = ret->next;
- ret->next = hashent[hash];
- hashent[hash] = ret;
- ret = next;
+ plan->join_hints[plan->njoin_hints] = hint;
+ plan->njoin_hints++;
+ }
}
- PG_RETURN_INT32(i);
+
+ bms_free(joinrelids);
}
-Datum
-pg_clear_hint(PG_FUNCTION_ARGS)
+static void
+rebuild_scan_path(PlanHint *plan, PlannerInfo *root, int level, List *initial_rels)
{
- int i;
- int n = 0;
+ int i;
+ int save_nestlevel = 0;
- for (i = 0 ; i < HASH_ENTRIES ; i++)
+ for (i = 0; i < plan->nscan_hints; i++)
{
- free_hashent(hashent[i]);
- hashent[i] = NULL;
- n++;
+ ScanHint *hint = plan->scan_hints[i];
+ ListCell *l;
+
+ if (hint->enforce_mask == ENABLE_SEQSCAN)
+ continue;
+ foreach(l, initial_rels)
+ {
+ RelOptInfo *rel = (RelOptInfo *) lfirst(l);
+ RangeTblEntry *rte = root->simple_rte_array[rel->relid];
+
+ if (rel->reloptkind != RELOPT_BASEREL ||
+ strcmp(hint->relname, rte->eref->aliasname) != 0)
+ continue;
+
+ if (save_nestlevel != 0)
+ save_nestlevel = NewGUCNestLevel();
+
+ /*
+ * TODO ヒントで指定されたScan方式が最安価でない場合のみ、Pathを生成
+ * しなおす
+ */
+ set_scan_config_options(hint->enforce_mask, plan->context);
+
+ rel->pathlist = NIL; // TODO 解放
+ set_plain_rel_pathlist(root, rel, rte);
+
+ break;
+ }
}
- PG_RETURN_INT32(n);
+
+ /*
+ * Restore the GUC variables we set above.
+ */
+ if (save_nestlevel != 0)
+ AtEOXact_GUC(true, save_nestlevel);
}
-Datum
-pg_enable_hint(bool arg, bool *isnull)
+/*
+ * src/backend/optimizer/path/joinrels.c
+ * export make_join_rel() をラップする関数
+ *
+ * ヒントにしたがって、enabele_* パラメータを変更した上で、make_join_rel()を
+ * 呼び出す。
+ */
+static RelOptInfo *
+pg_hint_plan_make_join_rel(PlannerInfo *root, RelOptInfo *rel1, RelOptInfo *rel2)
{
- tweak_enabled = arg;
- PG_RETURN_INT32(0);
+ Relids joinrelids;
+ JoinHint *hint;
+ RelOptInfo *rel;
+ int save_nestlevel;
+
+ joinrelids = bms_union(rel1->relids, rel2->relids);
+ hint = scan_join_hint(joinrelids);
+ bms_free(joinrelids);
+
+ if (!hint)
+ return make_join_rel(root, rel1, rel2);
+
+ save_nestlevel = NewGUCNestLevel();
+
+ set_join_config_options(hint->enforce_mask, global->context);
+
+ rel = make_join_rel(root, rel1, rel2);
+
+ /*
+ * Restore the GUC variables we set above.
+ */
+ AtEOXact_GUC(true, save_nestlevel);
+
+ return rel;
}
-Datum
-pg_enable_log(bool arg, bool *isnull)
+static RelOptInfo *_standard_join_search(PlannerInfo *root, int levels_needed, List *initial_rels);
+static RelOptInfo *
+pg_hint_plan_join_search(PlannerInfo *root, int levels_needed, List *initial_rels)
{
- print_log = arg;
- PG_RETURN_INT32(0);
+ /* 有効なヒントが指定されなかった場合は本来の処理を実行する。 */
+ if (!global)
+ {
+ if (prev_join_search)
+ return (*prev_join_search) (root, levels_needed, initial_rels);
+ else if (enable_geqo && levels_needed >= geqo_threshold)
+ return geqo(root, levels_needed, initial_rels);
+ else
+ return standard_join_search(root, levels_needed, initial_rels);
+ }
+
+ return _standard_join_search(root, levels_needed, initial_rels);
}
-static int putsbuf(char **p, char *bottom, char *str)
+/*
+ * PostgreSQL 本体から流用した関数
+ */
+
+/*
+ * src/backend/optimizer/path/allpaths.c
+ * export standard_join_search() を流用
+ *
+ * 変更箇所
+ * rebuild_join_hints() と rebuild_scan_path() の呼び出しを追加
+ */
+/*
+ * standard_join_search
+ * Find possible joinpaths for a query by successively finding ways
+ * to join component relations into join relations.
+ *
+ * 'levels_needed' is the number of iterations needed, ie, the number of
+ * independent jointree items in the query. This is > 1.
+ *
+ * 'initial_rels' is a list of RelOptInfo nodes for each independent
+ * jointree item. These are the components to be joined together.
+ * Note that levels_needed == list_length(initial_rels).
+ *
+ * Returns the final level of join relations, i.e., the relation that is
+ * the result of joining all the original relations together.
+ * At least one implementation path must be provided for this relation and
+ * all required sub-relations.
+ *
+ * To support loadable plugins that modify planner behavior by changing the
+ * join searching algorithm, we provide a hook variable that lets a plugin
+ * replace or supplement this function. Any such hook must return the same
+ * final join relation as the standard code would, but it might have a
+ * different set of implementation paths attached, and only the sub-joinrels
+ * needed for these paths need have been instantiated.
+ *
+ * Note to plugin authors: the functions invoked during standard_join_search()
+ * modify root->join_rel_list and root->join_rel_hash. If you want to do more
+ * than one join-order search, you'll probably need to save and restore the
+ * original states of those data structures. See geqo_eval() for an example.
+ */
+static RelOptInfo *
+_standard_join_search(PlannerInfo *root, int levels_needed, List *initial_rels)
{
- while (*p < bottom && *str)
+ int lev;
+ RelOptInfo *rel;
+
+ /*
+ * This function cannot be invoked recursively within any one planning
+ * problem, so join_rel_level[] can't be in use already.
+ */
+ Assert(root->join_rel_level == NULL);
+
+ /*
+ * We employ a simple "dynamic programming" algorithm: we first find all
+ * ways to build joins of two jointree items, then all ways to build joins
+ * of three items (from two-item joins and single items), then four-item
+ * joins, and so on until we have considered all ways to join all the
+ * items into one rel.
+ *
+ * root->join_rel_level[j] is a list of all the j-item rels. Initially we
+ * set root->join_rel_level[1] to represent all the single-jointree-item
+ * relations.
+ */
+ root->join_rel_level = (List **) palloc0((levels_needed + 1) * sizeof(List *));
+
+ root->join_rel_level[1] = initial_rels;
+
+ rebuild_join_hints(global, root, levels_needed, initial_rels);
+ rebuild_scan_path(global, root, levels_needed, initial_rels);
+
+ for (lev = 2; lev <= levels_needed; lev++)
{
- *(*p)++ = *str++;
+ ListCell *lc;
+
+ /*
+ * Determine all possible pairs of relations to be joined at this
+ * level, and build paths for making each one from every available
+ * pair of lower-level relations.
+ */
+ my_join_search_one_level(root, lev);
+
+ /*
+ * Do cleanup work on each just-processed rel.
+ */
+ foreach(lc, root->join_rel_level[lev])
+ {
+ rel = (RelOptInfo *) lfirst(lc);
+
+ /* Find and save the cheapest paths for this rel */
+ set_cheapest(rel);
+
+#ifdef OPTIMIZER_DEBUG
+ debug_print_rel(root, rel);
+#endif
+ }
}
- return (*str == 0);
+ /*
+ * We should have a single rel at the final level.
+ */
+ if (root->join_rel_level[levels_needed] == NIL)
+ elog(ERROR, "failed to build any %d-way joins", levels_needed);
+ Assert(list_length(root->join_rel_level[levels_needed]) == 1);
+
+ rel = (RelOptInfo *) linitial(root->join_rel_level[levels_needed]);
+
+ root->join_rel_level = NULL;
+
+ return rel;
}
-static void dump_ent(HashEntry *ent, char **p, char *bottom)
+/*
+ * src/backend/optimizer/path/joinrels.c
+ * join_search_one_level() を流用
+ *
+ * 変更箇所
+ * make_join_rel() の呼び出しをラップする、pg_hint_plan_make_join_rel()の呼び出しに変更
+ */
+/*
+ * join_search_one_level
+ * Consider ways to produce join relations containing exactly 'level'
+ * jointree items. (This is one step of the dynamic-programming method
+ * embodied in standard_join_search.) Join rel nodes for each feasible
+ * combination of lower-level rels are created and returned in a list.
+ * Implementation paths are created for each such joinrel, too.
+ *
+ * level: level of rels we want to make this time
+ * root->join_rel_level[j], 1 <= j < level, is a list of rels containing j items
+ *
+ * The result is returned in root->join_rel_level[level].
+ */
+static void
+my_join_search_one_level(PlannerInfo *root, int level)
{
- static char typesigs[] = "SIBTNMH";
- char sigs[sizeof(typesigs)];
- int i;
+ List **joinrels = root->join_rel_level;
+ ListCell *r;
+ int k;
+
+ Assert(joinrels[level] == NIL);
+
+ /* Set join_cur_level so that new joinrels are added to proper list */
+ root->join_cur_level = level;
+
+ /*
+ * First, consider left-sided and right-sided plans, in which rels of
+ * exactly level-1 member relations are joined against initial relations.
+ * We prefer to join using join clauses, but if we find a rel of level-1
+ * members that has no join clauses, we will generate Cartesian-product
+ * joins against all initial rels not already contained in it.
+ *
+ * In the first pass (level == 2), we try to join each initial rel to each
+ * initial rel that appears later in joinrels[1]. (The mirror-image joins
+ * are handled automatically by make_join_rel.) In later passes, we try
+ * to join rels of size level-1 from joinrels[level-1] to each initial rel
+ * in joinrels[1].
+ */
+ foreach(r, joinrels[level - 1])
+ {
+ RelOptInfo *old_rel = (RelOptInfo *) lfirst(r);
+ ListCell *other_rels;
+
+ if (level == 2)
+ other_rels = lnext(r); /* only consider remaining initial
+ * rels */
+ else
+ other_rels = list_head(joinrels[1]); /* consider all initial
+ * rels */
+
+ if (old_rel->joininfo != NIL || old_rel->has_eclass_joins ||
+ has_join_restriction(root, old_rel))
+ {
+ /*
+ * Note that if all available join clauses for this rel require
+ * more than one other rel, we will fail to make any joins against
+ * it here. In most cases that's OK; it'll be considered by
+ * "bushy plan" join code in a higher-level pass where we have
+ * those other rels collected into a join rel.
+ *
+ * See also the last-ditch case below.
+ */
+ make_rels_by_clause_joins(root,
+ old_rel,
+ other_rels);
+ }
+ else
+ {
+ /*
+ * Oops, we have a relation that is not joined to any other
+ * relation, either directly or by join-order restrictions.
+ * Cartesian product time.
+ */
+ make_rels_by_clauseless_joins(root,
+ old_rel,
+ other_rels);
+ }
+ }
+
+ /*
+ * Now, consider "bushy plans" in which relations of k initial rels are
+ * joined to relations of level-k initial rels, for 2 <= k <= level-2.
+ *
+ * We only consider bushy-plan joins for pairs of rels where there is a
+ * suitable join clause (or join order restriction), in order to avoid
+ * unreasonable growth of planning time.
+ */
+ for (k = 2;; k++)
+ {
+ int other_level = level - k;
+
+ /*
+ * Since make_join_rel(x, y) handles both x,y and y,x cases, we only
+ * need to go as far as the halfway point.
+ */
+ if (k > other_level)
+ break;
+
+ foreach(r, joinrels[k])
+ {
+ RelOptInfo *old_rel = (RelOptInfo *) lfirst(r);
+ ListCell *other_rels;
+ ListCell *r2;
+
+ /*
+ * We can ignore clauseless joins here, *except* when they
+ * participate in join-order restrictions --- then we might have
+ * to force a bushy join plan.
+ */
+ if (old_rel->joininfo == NIL && !old_rel->has_eclass_joins &&
+ !has_join_restriction(root, old_rel))
+ continue;
+
+ if (k == other_level)
+ other_rels = lnext(r); /* only consider remaining rels */
+ else
+ other_rels = list_head(joinrels[other_level]);
- if (!putsbuf(p, bottom, "[(")) return;
- for (i = 0 ; i < ent->tidlist.nrels ; i++)
+ for_each_cell(r2, other_rels)
+ {
+ RelOptInfo *new_rel = (RelOptInfo *) lfirst(r2);
+
+ if (!bms_overlap(old_rel->relids, new_rel->relids))
+ {
+ /*
+ * OK, we can build a rel of the right level from this
+ * pair of rels. Do so if there is at least one usable
+ * join clause or a relevant join restriction.
+ */
+ if (have_relevant_joinclause(root, old_rel, new_rel) ||
+ have_join_order_restriction(root, old_rel, new_rel))
+ {
+ (void) pg_hint_plan_make_join_rel(root, old_rel, new_rel);
+ }
+ }
+ }
+ }
+ }
+
+ /*
+ * Last-ditch effort: if we failed to find any usable joins so far, force
+ * a set of cartesian-product joins to be generated. This handles the
+ * special case where all the available rels have join clauses but we
+ * cannot use any of those clauses yet. An example is
+ *
+ * SELECT * FROM a,b,c WHERE (a.f1 + b.f2 + c.f3) = 0;
+ *
+ * The join clause will be usable at level 3, but at level 2 we have no
+ * choice but to make cartesian joins. We consider only left-sided and
+ * right-sided cartesian joins in this case (no bushy).
+ */
+ if (joinrels[level] == NIL)
{
- if (i && !putsbuf(p, bottom, ", ")) return;
- if (*p >= bottom) return;
- *p += snprintf(*p, bottom - *p, "%d", ent->tidlist.oids[i]);
+ /*
+ * This loop is just like the first one, except we always call
+ * make_rels_by_clauseless_joins().
+ */
+ foreach(r, joinrels[level - 1])
+ {
+ RelOptInfo *old_rel = (RelOptInfo *) lfirst(r);
+ ListCell *other_rels;
+
+ if (level == 2)
+ other_rels = lnext(r); /* only consider remaining initial
+ * rels */
+ else
+ other_rels = list_head(joinrels[1]); /* consider all initial
+ * rels */
+
+ make_rels_by_clauseless_joins(root,
+ old_rel,
+ other_rels);
+ }
+
+ /*----------
+ * When special joins are involved, there may be no legal way
+ * to make an N-way join for some values of N. For example consider
+ *
+ * SELECT ... FROM t1 WHERE
+ * x IN (SELECT ... FROM t2,t3 WHERE ...) AND
+ * y IN (SELECT ... FROM t4,t5 WHERE ...)
+ *
+ * We will flatten this query to a 5-way join problem, but there are
+ * no 4-way joins that join_is_legal() will consider legal. We have
+ * to accept failure at level 4 and go on to discover a workable
+ * bushy plan at level 5.
+ *
+ * However, if there are no special joins then join_is_legal() should
+ * never fail, and so the following sanity check is useful.
+ *----------
+ */
+ if (joinrels[level] == NIL && root->join_info_list == NIL)
+ elog(ERROR, "failed to build any %d-way joins", level);
}
- if (!putsbuf(p, bottom, "), ")) return;
- strcpy(sigs, typesigs);
- for (i = 0 ; i < 7 ; i++) /* Magic number here! */
+}
+
+/*
+ * src/backend/optimizer/path/joinrels.c
+ * static make_rels_by_clause_joins() を流用
+ *
+ * 変更箇所
+ * make_join_rel() の呼び出しをラップする、pg_hint_plan_make_join_rel()の呼び出しに変更
+ */
+/*
+ * make_rels_by_clause_joins
+ * Build joins between the given relation 'old_rel' and other relations
+ * that participate in join clauses that 'old_rel' also participates in
+ * (or participate in join-order restrictions with it).
+ * The join rels are returned in root->join_rel_level[join_cur_level].
+ *
+ * Note: at levels above 2 we will generate the same joined relation in
+ * multiple ways --- for example (a join b) join c is the same RelOptInfo as
+ * (b join c) join a, though the second case will add a different set of Paths
+ * to it. This is the reason for using the join_rel_level mechanism, which
+ * automatically ensures that each new joinrel is only added to the list once.
+ *
+ * 'old_rel' is the relation entry for the relation to be joined
+ * 'other_rels': the first cell in a linked list containing the other
+ * rels to be considered for joining
+ *
+ * Currently, this is only used with initial rels in other_rels, but it
+ * will work for joining to joinrels too.
+ */
+static void
+make_rels_by_clause_joins(PlannerInfo *root,
+ RelOptInfo *old_rel,
+ ListCell *other_rels)
+{
+ ListCell *l;
+
+ for_each_cell(l, other_rels)
{
- if(((1<<i) & ent->enforce_mask) == 0)
- sigs[i] += 'a' - 'A';
+ RelOptInfo *other_rel = (RelOptInfo *) lfirst(l);
+
+ if (!bms_overlap(old_rel->relids, other_rel->relids) &&
+ (have_relevant_joinclause(root, old_rel, other_rel) ||
+ have_join_order_restriction(root, old_rel, other_rel)))
+ {
+ (void) pg_hint_plan_make_join_rel(root, old_rel, other_rel);
+ }
}
- if (!putsbuf(p, bottom, sigs)) return;
- if (!putsbuf(p, bottom, "]")) return;
}
-Datum
-pg_dump_hint(PG_FUNCTION_ARGS)
+/*
+ * src/backend/optimizer/path/joinrels.c
+ * static make_rels_by_clauseless_joins() を流用
+ *
+ * 変更箇所
+ * make_join_rel() の呼び出しをラップする、pg_hint_plan_make_join_rel()の呼び出しに変更
+ */
+/*
+ * make_rels_by_clauseless_joins
+ * Given a relation 'old_rel' and a list of other relations
+ * 'other_rels', create a join relation between 'old_rel' and each
+ * member of 'other_rels' that isn't already included in 'old_rel'.
+ * The join rels are returned in root->join_rel_level[join_cur_level].
+ *
+ * 'old_rel' is the relation entry for the relation to be joined
+ * 'other_rels': the first cell of a linked list containing the
+ * other rels to be considered for joining
+ *
+ * Currently, this is only used with initial rels in other_rels, but it would
+ * work for joining to joinrels too.
+ */
+static void
+make_rels_by_clauseless_joins(PlannerInfo *root,
+ RelOptInfo *old_rel,
+ ListCell *other_rels)
{
- char buf[16384]; /* ^^; */
- char *bottom = buf + sizeof(buf);
- char *p = buf;
- int i;
- int first = 1;
+ ListCell *l;
- memset(buf, 0, sizeof(buf));
- for (i = 0 ; i < HASH_ENTRIES ; i++)
+ for_each_cell(l, other_rels)
{
- if (hashent[i])
+ RelOptInfo *other_rel = (RelOptInfo *) lfirst(l);
+
+ if (!bms_overlap(other_rel->relids, old_rel->relids))
{
- HashEntry *ent = hashent[i];
- while (ent)
- {
- if (first)
- first = 0;
- else
- putsbuf(&p, bottom, ", ");
-
- dump_ent(ent, &p, bottom);
- ent = ent->next;
- }
+ (void) pg_hint_plan_make_join_rel(root, old_rel, other_rel);
}
}
- if (p >= bottom) p--;
- *p = 0;
-
- PG_RETURN_CSTRING(cstring_to_text(buf));
+}
+
+/*
+ * src/backend/optimizer/path/joinrels.c
+ * static has_join_restriction() を流用
+ *
+ * 変更箇所
+ * なし
+ */
+/*
+ * has_join_restriction
+ * Detect whether the specified relation has join-order restrictions
+ * due to being inside an outer join or an IN (sub-SELECT).
+ *
+ * Essentially, this tests whether have_join_order_restriction() could
+ * succeed with this rel and some other one. It's OK if we sometimes
+ * say "true" incorrectly. (Therefore, we don't bother with the relatively
+ * expensive has_legal_joinclause test.)
+ */
+static bool
+has_join_restriction(PlannerInfo *root, RelOptInfo *rel)
+{
+ ListCell *l;
+
+ foreach(l, root->join_info_list)
+ {
+ SpecialJoinInfo *sjinfo = (SpecialJoinInfo *) lfirst(l);
+
+ /* ignore full joins --- other mechanisms preserve their ordering */
+ if (sjinfo->jointype == JOIN_FULL)
+ continue;
+
+ /* ignore if SJ is already contained in rel */
+ if (bms_is_subset(sjinfo->min_lefthand, rel->relids) &&
+ bms_is_subset(sjinfo->min_righthand, rel->relids))
+ continue;
+
+ /* restricted if it overlaps LHS or RHS, but doesn't contain SJ */
+ if (bms_overlap(sjinfo->min_lefthand, rel->relids) ||
+ bms_overlap(sjinfo->min_righthand, rel->relids))
+ return true;
+ }
+
+ return false;
+}
+
+/*
+ * src/backend/optimizer/path/allpaths.c
+ * static set_plain_rel_pathlist() を流用
+ *
+ * 変更箇所
+ * なし
+ */
+/*
+ * set_plain_rel_pathlist
+ * Build access paths for a plain relation (no subquery, no inheritance)
+ */
+static void
+set_plain_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
+{
+ /* Consider sequential scan */
+ add_path(rel, create_seqscan_path(root, rel));
+
+ /* Consider index scans */
+ create_index_paths(root, rel);
+
+ /* Consider TID scans */
+ create_tidscan_paths(root, rel);
+
+ /* Now find the cheapest of the paths for this rel */
+ set_cheapest(rel);
}
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