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explain.c
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explain.c
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/*-------------------------------------------------------------------------
*
* explain.c
* Explain query execution plans
*
* Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
* Portions Copyright (c) 1994-5, Regents of the University of California
*
* IDENTIFICATION
* src/backend/commands/explain.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/xact.h"
#include "catalog/pg_type.h"
#include "commands/createas.h"
#include "commands/defrem.h"
#include "commands/prepare.h"
#include "executor/nodeHash.h"
#include "foreign/fdwapi.h"
#include "jit/jit.h"
#include "nodes/extensible.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "parser/analyze.h"
#include "parser/parsetree.h"
#include "rewrite/rewriteHandler.h"
#include "storage/bufmgr.h"
#include "tcop/tcopprot.h"
#include "utils/builtins.h"
#include "utils/guc_tables.h"
#include "utils/json.h"
#include "utils/lsyscache.h"
#include "utils/rel.h"
#include "utils/ruleutils.h"
#include "utils/snapmgr.h"
#include "utils/tuplesort.h"
#include "utils/typcache.h"
#include "utils/xml.h"
/* Hook for plugins to get control in ExplainOneQuery() */
ExplainOneQuery_hook_type ExplainOneQuery_hook = NULL;
/* Hook for plugins to get control in explain_get_index_name() */
explain_get_index_name_hook_type explain_get_index_name_hook = NULL;
/* OR-able flags for ExplainXMLTag() */
#define X_OPENING 0
#define X_CLOSING 1
#define X_CLOSE_IMMEDIATE 2
#define X_NOWHITESPACE 4
static void ExplainOneQuery(Query *query, int cursorOptions,
IntoClause *into, ExplainState *es,
const char *queryString, ParamListInfo params,
QueryEnvironment *queryEnv);
static void ExplainPrintJIT(ExplainState *es, int jit_flags,
JitInstrumentation *ji);
static void report_triggers(ResultRelInfo *rInfo, bool show_relname,
ExplainState *es);
static double elapsed_time(instr_time *starttime);
static bool ExplainPreScanNode(PlanState *planstate, Bitmapset **rels_used);
static void ExplainNode(PlanState *planstate, List *ancestors,
const char *relationship, const char *plan_name,
ExplainState *es);
static void show_plan_tlist(PlanState *planstate, List *ancestors,
ExplainState *es);
static void show_expression(Node *node, const char *qlabel,
PlanState *planstate, List *ancestors,
bool useprefix, ExplainState *es);
static void show_qual(List *qual, const char *qlabel,
PlanState *planstate, List *ancestors,
bool useprefix, ExplainState *es);
static void show_scan_qual(List *qual, const char *qlabel,
PlanState *planstate, List *ancestors,
ExplainState *es);
static void show_upper_qual(List *qual, const char *qlabel,
PlanState *planstate, List *ancestors,
ExplainState *es);
static void show_sort_keys(SortState *sortstate, List *ancestors,
ExplainState *es);
static void show_incremental_sort_keys(IncrementalSortState *incrsortstate,
List *ancestors, ExplainState *es);
static void show_merge_append_keys(MergeAppendState *mstate, List *ancestors,
ExplainState *es);
static void show_agg_keys(AggState *astate, List *ancestors,
ExplainState *es);
static void show_grouping_sets(PlanState *planstate, Agg *agg,
List *ancestors, ExplainState *es);
static void show_grouping_set_keys(PlanState *planstate,
Agg *aggnode, Sort *sortnode,
List *context, bool useprefix,
List *ancestors, ExplainState *es);
static void show_group_keys(GroupState *gstate, List *ancestors,
ExplainState *es);
static void show_sort_group_keys(PlanState *planstate, const char *qlabel,
int nkeys, int nPresortedKeys, AttrNumber *keycols,
Oid *sortOperators, Oid *collations, bool *nullsFirst,
List *ancestors, ExplainState *es);
static void show_sortorder_options(StringInfo buf, Node *sortexpr,
Oid sortOperator, Oid collation, bool nullsFirst);
static void show_tablesample(TableSampleClause *tsc, PlanState *planstate,
List *ancestors, ExplainState *es);
static void show_sort_info(SortState *sortstate, ExplainState *es);
static void show_incremental_sort_info(IncrementalSortState *incrsortstate,
ExplainState *es);
static void show_hash_info(HashState *hashstate, ExplainState *es);
static void show_memoize_info(MemoizeState *mstate, List *ancestors,
ExplainState *es);
static void show_hashagg_info(AggState *aggstate, ExplainState *es);
static void show_tidbitmap_info(BitmapHeapScanState *planstate,
ExplainState *es);
static void show_instrumentation_count(const char *qlabel, int which,
PlanState *planstate, ExplainState *es);
static void show_foreignscan_info(ForeignScanState *fsstate, ExplainState *es);
static void show_eval_params(Bitmapset *bms_params, ExplainState *es);
static const char *explain_get_index_name(Oid indexId);
static void show_buffer_usage(ExplainState *es, const BufferUsage *usage,
bool planning);
static void show_wal_usage(ExplainState *es, const WalUsage *usage);
static void ExplainIndexScanDetails(Oid indexid, ScanDirection indexorderdir,
ExplainState *es);
static void ExplainScanTarget(Scan *plan, ExplainState *es);
static void ExplainModifyTarget(ModifyTable *plan, ExplainState *es);
static void ExplainTargetRel(Plan *plan, Index rti, ExplainState *es);
static void show_modifytable_info(ModifyTableState *mtstate, List *ancestors,
ExplainState *es);
static void ExplainMemberNodes(PlanState **planstates, int nplans,
List *ancestors, ExplainState *es);
static void ExplainMissingMembers(int nplans, int nchildren, ExplainState *es);
static void ExplainSubPlans(List *plans, List *ancestors,
const char *relationship, ExplainState *es);
static void ExplainCustomChildren(CustomScanState *css,
List *ancestors, ExplainState *es);
static ExplainWorkersState *ExplainCreateWorkersState(int num_workers);
static void ExplainOpenWorker(int n, ExplainState *es);
static void ExplainCloseWorker(int n, ExplainState *es);
static void ExplainFlushWorkersState(ExplainState *es);
static void ExplainProperty(const char *qlabel, const char *unit,
const char *value, bool numeric, ExplainState *es);
static void ExplainOpenSetAsideGroup(const char *objtype, const char *labelname,
bool labeled, int depth, ExplainState *es);
static void ExplainSaveGroup(ExplainState *es, int depth, int *state_save);
static void ExplainRestoreGroup(ExplainState *es, int depth, int *state_save);
static void ExplainDummyGroup(const char *objtype, const char *labelname,
ExplainState *es);
static void ExplainXMLTag(const char *tagname, int flags, ExplainState *es);
static void ExplainIndentText(ExplainState *es);
static void ExplainJSONLineEnding(ExplainState *es);
static void ExplainYAMLLineStarting(ExplainState *es);
static void escape_yaml(StringInfo buf, const char *str);
/*
* ExplainQuery -
* execute an EXPLAIN command
*/
void
ExplainQuery(ParseState *pstate, ExplainStmt *stmt,
ParamListInfo params, DestReceiver *dest)
{
ExplainState *es = NewExplainState();
TupOutputState *tstate;
JumbleState *jstate = NULL;
Query *query;
List *rewritten;
ListCell *lc;
bool timing_set = false;
bool summary_set = false;
/* Parse options list. */
foreach(lc, stmt->options)
{
DefElem *opt = (DefElem *) lfirst(lc);
if (strcmp(opt->defname, "analyze") == 0)
es->analyze = defGetBoolean(opt);
else if (strcmp(opt->defname, "verbose") == 0)
es->verbose = defGetBoolean(opt);
else if (strcmp(opt->defname, "costs") == 0)
es->costs = defGetBoolean(opt);
else if (strcmp(opt->defname, "buffers") == 0)
es->buffers = defGetBoolean(opt);
else if (strcmp(opt->defname, "wal") == 0)
es->wal = defGetBoolean(opt);
else if (strcmp(opt->defname, "settings") == 0)
es->settings = defGetBoolean(opt);
else if (strcmp(opt->defname, "generic_plan") == 0)
es->generic = defGetBoolean(opt);
else if (strcmp(opt->defname, "timing") == 0)
{
timing_set = true;
es->timing = defGetBoolean(opt);
}
else if (strcmp(opt->defname, "summary") == 0)
{
summary_set = true;
es->summary = defGetBoolean(opt);
}
else if (strcmp(opt->defname, "format") == 0)
{
char *p = defGetString(opt);
if (strcmp(p, "text") == 0)
es->format = EXPLAIN_FORMAT_TEXT;
else if (strcmp(p, "xml") == 0)
es->format = EXPLAIN_FORMAT_XML;
else if (strcmp(p, "json") == 0)
es->format = EXPLAIN_FORMAT_JSON;
else if (strcmp(p, "yaml") == 0)
es->format = EXPLAIN_FORMAT_YAML;
else
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("unrecognized value for EXPLAIN option \"%s\": \"%s\"",
opt->defname, p),
parser_errposition(pstate, opt->location)));
}
else
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("unrecognized EXPLAIN option \"%s\"",
opt->defname),
parser_errposition(pstate, opt->location)));
}
/* check that WAL is used with EXPLAIN ANALYZE */
if (es->wal && !es->analyze)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("EXPLAIN option WAL requires ANALYZE")));
/* if the timing was not set explicitly, set default value */
es->timing = (timing_set) ? es->timing : es->analyze;
/* check that timing is used with EXPLAIN ANALYZE */
if (es->timing && !es->analyze)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("EXPLAIN option TIMING requires ANALYZE")));
/* check that GENERIC_PLAN is not used with EXPLAIN ANALYZE */
if (es->generic && es->analyze)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("EXPLAIN options ANALYZE and GENERIC_PLAN cannot be used together")));
/* if the summary was not set explicitly, set default value */
es->summary = (summary_set) ? es->summary : es->analyze;
query = castNode(Query, stmt->query);
if (IsQueryIdEnabled())
jstate = JumbleQuery(query);
if (post_parse_analyze_hook)
(*post_parse_analyze_hook) (pstate, query, jstate);
/*
* Parse analysis was done already, but we still have to run the rule
* rewriter. We do not do AcquireRewriteLocks: we assume the query either
* came straight from the parser, or suitable locks were acquired by
* plancache.c.
*/
rewritten = QueryRewrite(castNode(Query, stmt->query));
/* emit opening boilerplate */
ExplainBeginOutput(es);
if (rewritten == NIL)
{
/*
* In the case of an INSTEAD NOTHING, tell at least that. But in
* non-text format, the output is delimited, so this isn't necessary.
*/
if (es->format == EXPLAIN_FORMAT_TEXT)
appendStringInfoString(es->str, "Query rewrites to nothing\n");
}
else
{
ListCell *l;
/* Explain every plan */
foreach(l, rewritten)
{
ExplainOneQuery(lfirst_node(Query, l),
CURSOR_OPT_PARALLEL_OK, NULL, es,
pstate->p_sourcetext, params, pstate->p_queryEnv);
/* Separate plans with an appropriate separator */
if (lnext(rewritten, l) != NULL)
ExplainSeparatePlans(es);
}
}
/* emit closing boilerplate */
ExplainEndOutput(es);
Assert(es->indent == 0);
/* output tuples */
tstate = begin_tup_output_tupdesc(dest, ExplainResultDesc(stmt),
&TTSOpsVirtual);
if (es->format == EXPLAIN_FORMAT_TEXT)
do_text_output_multiline(tstate, es->str->data);
else
do_text_output_oneline(tstate, es->str->data);
end_tup_output(tstate);
pfree(es->str->data);
}
/*
* Create a new ExplainState struct initialized with default options.
*/
ExplainState *
NewExplainState(void)
{
ExplainState *es = (ExplainState *) palloc0(sizeof(ExplainState));
/* Set default options (most fields can be left as zeroes). */
es->costs = true;
/* Prepare output buffer. */
es->str = makeStringInfo();
return es;
}
/*
* ExplainResultDesc -
* construct the result tupledesc for an EXPLAIN
*/
TupleDesc
ExplainResultDesc(ExplainStmt *stmt)
{
TupleDesc tupdesc;
ListCell *lc;
Oid result_type = TEXTOID;
/* Check for XML format option */
foreach(lc, stmt->options)
{
DefElem *opt = (DefElem *) lfirst(lc);
if (strcmp(opt->defname, "format") == 0)
{
char *p = defGetString(opt);
if (strcmp(p, "xml") == 0)
result_type = XMLOID;
else if (strcmp(p, "json") == 0)
result_type = JSONOID;
else
result_type = TEXTOID;
/* don't "break", as ExplainQuery will use the last value */
}
}
/* Need a tuple descriptor representing a single TEXT or XML column */
tupdesc = CreateTemplateTupleDesc(1);
TupleDescInitEntry(tupdesc, (AttrNumber) 1, "QUERY PLAN",
result_type, -1, 0);
return tupdesc;
}
/*
* ExplainOneQuery -
* print out the execution plan for one Query
*
* "into" is NULL unless we are explaining the contents of a CreateTableAsStmt.
*/
static void
ExplainOneQuery(Query *query, int cursorOptions,
IntoClause *into, ExplainState *es,
const char *queryString, ParamListInfo params,
QueryEnvironment *queryEnv)
{
/* planner will not cope with utility statements */
if (query->commandType == CMD_UTILITY)
{
ExplainOneUtility(query->utilityStmt, into, es, queryString, params,
queryEnv);
return;
}
/* if an advisor plugin is present, let it manage things */
if (ExplainOneQuery_hook)
(*ExplainOneQuery_hook) (query, cursorOptions, into, es,
queryString, params, queryEnv);
else
{
PlannedStmt *plan;
instr_time planstart,
planduration;
BufferUsage bufusage_start,
bufusage;
if (es->buffers)
bufusage_start = pgBufferUsage;
INSTR_TIME_SET_CURRENT(planstart);
/* plan the query */
plan = pg_plan_query(query, queryString, cursorOptions, params);
INSTR_TIME_SET_CURRENT(planduration);
INSTR_TIME_SUBTRACT(planduration, planstart);
/* calc differences of buffer counters. */
if (es->buffers)
{
memset(&bufusage, 0, sizeof(BufferUsage));
BufferUsageAccumDiff(&bufusage, &pgBufferUsage, &bufusage_start);
}
/* run it (if needed) and produce output */
ExplainOnePlan(plan, into, es, queryString, params, queryEnv,
&planduration, (es->buffers ? &bufusage : NULL));
}
}
/*
* ExplainOneUtility -
* print out the execution plan for one utility statement
* (In general, utility statements don't have plans, but there are some
* we treat as special cases)
*
* "into" is NULL unless we are explaining the contents of a CreateTableAsStmt.
*
* This is exported because it's called back from prepare.c in the
* EXPLAIN EXECUTE case. In that case, we'll be dealing with a statement
* that's in the plan cache, so we have to ensure we don't modify it.
*/
void
ExplainOneUtility(Node *utilityStmt, IntoClause *into, ExplainState *es,
const char *queryString, ParamListInfo params,
QueryEnvironment *queryEnv)
{
if (utilityStmt == NULL)
return;
if (IsA(utilityStmt, CreateTableAsStmt))
{
/*
* We have to rewrite the contained SELECT and then pass it back to
* ExplainOneQuery. Copy to be safe in the EXPLAIN EXECUTE case.
*/
CreateTableAsStmt *ctas = (CreateTableAsStmt *) utilityStmt;
List *rewritten;
/*
* Check if the relation exists or not. This is done at this stage to
* avoid query planning or execution.
*/
if (CreateTableAsRelExists(ctas))
{
if (ctas->objtype == OBJECT_TABLE)
ExplainDummyGroup("CREATE TABLE AS", NULL, es);
else if (ctas->objtype == OBJECT_MATVIEW)
ExplainDummyGroup("CREATE MATERIALIZED VIEW", NULL, es);
else
elog(ERROR, "unexpected object type: %d",
(int) ctas->objtype);
return;
}
rewritten = QueryRewrite(castNode(Query, copyObject(ctas->query)));
Assert(list_length(rewritten) == 1);
ExplainOneQuery(linitial_node(Query, rewritten),
CURSOR_OPT_PARALLEL_OK, ctas->into, es,
queryString, params, queryEnv);
}
else if (IsA(utilityStmt, DeclareCursorStmt))
{
/*
* Likewise for DECLARE CURSOR.
*
* Notice that if you say EXPLAIN ANALYZE DECLARE CURSOR then we'll
* actually run the query. This is different from pre-8.3 behavior
* but seems more useful than not running the query. No cursor will
* be created, however.
*/
DeclareCursorStmt *dcs = (DeclareCursorStmt *) utilityStmt;
List *rewritten;
rewritten = QueryRewrite(castNode(Query, copyObject(dcs->query)));
Assert(list_length(rewritten) == 1);
ExplainOneQuery(linitial_node(Query, rewritten),
dcs->options, NULL, es,
queryString, params, queryEnv);
}
else if (IsA(utilityStmt, ExecuteStmt))
ExplainExecuteQuery((ExecuteStmt *) utilityStmt, into, es,
queryString, params, queryEnv);
else if (IsA(utilityStmt, NotifyStmt))
{
if (es->format == EXPLAIN_FORMAT_TEXT)
appendStringInfoString(es->str, "NOTIFY\n");
else
ExplainDummyGroup("Notify", NULL, es);
}
else
{
if (es->format == EXPLAIN_FORMAT_TEXT)
appendStringInfoString(es->str,
"Utility statements have no plan structure\n");
else
ExplainDummyGroup("Utility Statement", NULL, es);
}
}
/*
* ExplainOnePlan -
* given a planned query, execute it if needed, and then print
* EXPLAIN output
*
* "into" is NULL unless we are explaining the contents of a CreateTableAsStmt,
* in which case executing the query should result in creating that table.
*
* This is exported because it's called back from prepare.c in the
* EXPLAIN EXECUTE case, and because an index advisor plugin would need
* to call it.
*/
void
ExplainOnePlan(PlannedStmt *plannedstmt, IntoClause *into, ExplainState *es,
const char *queryString, ParamListInfo params,
QueryEnvironment *queryEnv, const instr_time *planduration,
const BufferUsage *bufusage)
{
DestReceiver *dest;
QueryDesc *queryDesc;
instr_time starttime;
double totaltime = 0;
int eflags;
int instrument_option = 0;
Assert(plannedstmt->commandType != CMD_UTILITY);
if (es->analyze && es->timing)
instrument_option |= INSTRUMENT_TIMER;
else if (es->analyze)
instrument_option |= INSTRUMENT_ROWS;
if (es->buffers)
instrument_option |= INSTRUMENT_BUFFERS;
if (es->wal)
instrument_option |= INSTRUMENT_WAL;
/*
* We always collect timing for the entire statement, even when node-level
* timing is off, so we don't look at es->timing here. (We could skip
* this if !es->summary, but it's hardly worth the complication.)
*/
INSTR_TIME_SET_CURRENT(starttime);
/*
* Use a snapshot with an updated command ID to ensure this query sees
* results of any previously executed queries.
*/
PushCopiedSnapshot(GetActiveSnapshot());
UpdateActiveSnapshotCommandId();
/*
* Normally we discard the query's output, but if explaining CREATE TABLE
* AS, we'd better use the appropriate tuple receiver.
*/
if (into)
dest = CreateIntoRelDestReceiver(into);
else
dest = None_Receiver;
/* Create a QueryDesc for the query */
queryDesc = CreateQueryDesc(plannedstmt, queryString,
GetActiveSnapshot(), InvalidSnapshot,
dest, params, queryEnv, instrument_option);
/* Select execution options */
if (es->analyze)
eflags = 0; /* default run-to-completion flags */
else
eflags = EXEC_FLAG_EXPLAIN_ONLY;
if (es->generic)
eflags |= EXEC_FLAG_EXPLAIN_GENERIC;
if (into)
eflags |= GetIntoRelEFlags(into);
/* call ExecutorStart to prepare the plan for execution */
ExecutorStart(queryDesc, eflags);
/* Execute the plan for statistics if asked for */
if (es->analyze)
{
ScanDirection dir;
/* EXPLAIN ANALYZE CREATE TABLE AS WITH NO DATA is weird */
if (into && into->skipData)
dir = NoMovementScanDirection;
else
dir = ForwardScanDirection;
/* run the plan */
ExecutorRun(queryDesc, dir, 0, true);
/* run cleanup too */
ExecutorFinish(queryDesc);
/* We can't run ExecutorEnd 'till we're done printing the stats... */
totaltime += elapsed_time(&starttime);
}
ExplainOpenGroup("Query", NULL, true, es);
/* Create textual dump of plan tree */
ExplainPrintPlan(es, queryDesc);
/* Show buffer usage in planning */
if (bufusage)
{
ExplainOpenGroup("Planning", "Planning", true, es);
show_buffer_usage(es, bufusage, true);
ExplainCloseGroup("Planning", "Planning", true, es);
}
if (es->summary && planduration)
{
double plantime = INSTR_TIME_GET_DOUBLE(*planduration);
ExplainPropertyFloat("Planning Time", "ms", 1000.0 * plantime, 3, es);
}
/* Print info about runtime of triggers */
if (es->analyze)
ExplainPrintTriggers(es, queryDesc);
/*
* Print info about JITing. Tied to es->costs because we don't want to
* display this in regression tests, as it'd cause output differences
* depending on build options. Might want to separate that out from COSTS
* at a later stage.
*/
if (es->costs)
ExplainPrintJITSummary(es, queryDesc);
/*
* Close down the query and free resources. Include time for this in the
* total execution time (although it should be pretty minimal).
*/
INSTR_TIME_SET_CURRENT(starttime);
ExecutorEnd(queryDesc);
FreeQueryDesc(queryDesc);
PopActiveSnapshot();
/* We need a CCI just in case query expanded to multiple plans */
if (es->analyze)
CommandCounterIncrement();
totaltime += elapsed_time(&starttime);
/*
* We only report execution time if we actually ran the query (that is,
* the user specified ANALYZE), and if summary reporting is enabled (the
* user can set SUMMARY OFF to not have the timing information included in
* the output). By default, ANALYZE sets SUMMARY to true.
*/
if (es->summary && es->analyze)
ExplainPropertyFloat("Execution Time", "ms", 1000.0 * totaltime, 3,
es);
ExplainCloseGroup("Query", NULL, true, es);
}
/*
* ExplainPrintSettings -
* Print summary of modified settings affecting query planning.
*/
static void
ExplainPrintSettings(ExplainState *es)
{
int num;
struct config_generic **gucs;
/* bail out if information about settings not requested */
if (!es->settings)
return;
/* request an array of relevant settings */
gucs = get_explain_guc_options(&num);
if (es->format != EXPLAIN_FORMAT_TEXT)
{
ExplainOpenGroup("Settings", "Settings", true, es);
for (int i = 0; i < num; i++)
{
char *setting;
struct config_generic *conf = gucs[i];
setting = GetConfigOptionByName(conf->name, NULL, true);
ExplainPropertyText(conf->name, setting, es);
}
ExplainCloseGroup("Settings", "Settings", true, es);
}
else
{
StringInfoData str;
/* In TEXT mode, print nothing if there are no options */
if (num <= 0)
return;
initStringInfo(&str);
for (int i = 0; i < num; i++)
{
char *setting;
struct config_generic *conf = gucs[i];
if (i > 0)
appendStringInfoString(&str, ", ");
setting = GetConfigOptionByName(conf->name, NULL, true);
if (setting)
appendStringInfo(&str, "%s = '%s'", conf->name, setting);
else
appendStringInfo(&str, "%s = NULL", conf->name);
}
ExplainPropertyText("Settings", str.data, es);
}
}
/*
* ExplainPrintPlan -
* convert a QueryDesc's plan tree to text and append it to es->str
*
* The caller should have set up the options fields of *es, as well as
* initializing the output buffer es->str. Also, output formatting state
* such as the indent level is assumed valid. Plan-tree-specific fields
* in *es are initialized here.
*
* NB: will not work on utility statements
*/
void
ExplainPrintPlan(ExplainState *es, QueryDesc *queryDesc)
{
Bitmapset *rels_used = NULL;
PlanState *ps;
/* Set up ExplainState fields associated with this plan tree */
Assert(queryDesc->plannedstmt != NULL);
es->pstmt = queryDesc->plannedstmt;
es->rtable = queryDesc->plannedstmt->rtable;
ExplainPreScanNode(queryDesc->planstate, &rels_used);
es->rtable_names = select_rtable_names_for_explain(es->rtable, rels_used);
es->deparse_cxt = deparse_context_for_plan_tree(queryDesc->plannedstmt,
es->rtable_names);
es->printed_subplans = NULL;
/*
* Sometimes we mark a Gather node as "invisible", which means that it's
* not to be displayed in EXPLAIN output. The purpose of this is to allow
* running regression tests with debug_parallel_query=regress to get the
* same results as running the same tests with debug_parallel_query=off.
* Such marking is currently only supported on a Gather at the top of the
* plan. We skip that node, and we must also hide per-worker detail data
* further down in the plan tree.
*/
ps = queryDesc->planstate;
if (IsA(ps, GatherState) && ((Gather *) ps->plan)->invisible)
{
ps = outerPlanState(ps);
es->hide_workers = true;
}
ExplainNode(ps, NIL, NULL, NULL, es);
/*
* If requested, include information about GUC parameters with values that
* don't match the built-in defaults.
*/
ExplainPrintSettings(es);
/*
* COMPUTE_QUERY_ID_REGRESS means COMPUTE_QUERY_ID_AUTO, but we don't show
* the queryid in any of the EXPLAIN plans to keep stable the results
* generated by regression test suites.
*/
if (es->verbose && queryDesc->plannedstmt->queryId != UINT64CONST(0) &&
compute_query_id != COMPUTE_QUERY_ID_REGRESS)
{
/*
* Output the queryid as an int64 rather than a uint64 so we match
* what would be seen in the BIGINT pg_stat_statements.queryid column.
*/
ExplainPropertyInteger("Query Identifier", NULL, (int64)
queryDesc->plannedstmt->queryId, es);
}
}
/*
* ExplainPrintTriggers -
* convert a QueryDesc's trigger statistics to text and append it to
* es->str
*
* The caller should have set up the options fields of *es, as well as
* initializing the output buffer es->str. Other fields in *es are
* initialized here.
*/
void
ExplainPrintTriggers(ExplainState *es, QueryDesc *queryDesc)
{
ResultRelInfo *rInfo;
bool show_relname;
List *resultrels;
List *routerels;
List *targrels;
ListCell *l;
resultrels = queryDesc->estate->es_opened_result_relations;
routerels = queryDesc->estate->es_tuple_routing_result_relations;
targrels = queryDesc->estate->es_trig_target_relations;
ExplainOpenGroup("Triggers", "Triggers", false, es);
show_relname = (list_length(resultrels) > 1 ||
routerels != NIL || targrels != NIL);
foreach(l, resultrels)
{
rInfo = (ResultRelInfo *) lfirst(l);
report_triggers(rInfo, show_relname, es);
}
foreach(l, routerels)
{
rInfo = (ResultRelInfo *) lfirst(l);
report_triggers(rInfo, show_relname, es);
}
foreach(l, targrels)
{
rInfo = (ResultRelInfo *) lfirst(l);
report_triggers(rInfo, show_relname, es);
}
ExplainCloseGroup("Triggers", "Triggers", false, es);
}
/*
* ExplainPrintJITSummary -
* Print summarized JIT instrumentation from leader and workers
*/
void
ExplainPrintJITSummary(ExplainState *es, QueryDesc *queryDesc)
{
JitInstrumentation ji = {0};
if (!(queryDesc->estate->es_jit_flags & PGJIT_PERFORM))
return;
/*
* Work with a copy instead of modifying the leader state, since this
* function may be called twice
*/
if (queryDesc->estate->es_jit)
InstrJitAgg(&ji, &queryDesc->estate->es_jit->instr);
/* If this process has done JIT in parallel workers, merge stats */
if (queryDesc->estate->es_jit_worker_instr)
InstrJitAgg(&ji, queryDesc->estate->es_jit_worker_instr);
ExplainPrintJIT(es, queryDesc->estate->es_jit_flags, &ji);
}
/*
* ExplainPrintJIT -
* Append information about JITing to es->str.
*/
static void
ExplainPrintJIT(ExplainState *es, int jit_flags, JitInstrumentation *ji)
{
instr_time total_time;
/* don't print information if no JITing happened */
if (!ji || ji->created_functions == 0)
return;
/* calculate total time */
INSTR_TIME_SET_ZERO(total_time);
/* don't add deform_counter, it's included in generation_counter */
INSTR_TIME_ADD(total_time, ji->generation_counter);
INSTR_TIME_ADD(total_time, ji->inlining_counter);
INSTR_TIME_ADD(total_time, ji->optimization_counter);
INSTR_TIME_ADD(total_time, ji->emission_counter);
ExplainOpenGroup("JIT", "JIT", true, es);
/* for higher density, open code the text output format */
if (es->format == EXPLAIN_FORMAT_TEXT)
{
ExplainIndentText(es);
appendStringInfoString(es->str, "JIT:\n");
es->indent++;
ExplainPropertyInteger("Functions", NULL, ji->created_functions, es);
ExplainIndentText(es);
appendStringInfo(es->str, "Options: %s %s, %s %s, %s %s, %s %s\n",
"Inlining", jit_flags & PGJIT_INLINE ? "true" : "false",
"Optimization", jit_flags & PGJIT_OPT3 ? "true" : "false",
"Expressions", jit_flags & PGJIT_EXPR ? "true" : "false",
"Deforming", jit_flags & PGJIT_DEFORM ? "true" : "false");
if (es->analyze && es->timing)
{
ExplainIndentText(es);
appendStringInfo(es->str,
"Timing: %s %.3f ms (%s %.3f ms), %s %.3f ms, %s %.3f ms, %s %.3f ms, %s %.3f ms\n",
"Generation", 1000.0 * INSTR_TIME_GET_DOUBLE(ji->generation_counter),
"Deform", 1000.0 * INSTR_TIME_GET_DOUBLE(ji->deform_counter),
"Inlining", 1000.0 * INSTR_TIME_GET_DOUBLE(ji->inlining_counter),
"Optimization", 1000.0 * INSTR_TIME_GET_DOUBLE(ji->optimization_counter),
"Emission", 1000.0 * INSTR_TIME_GET_DOUBLE(ji->emission_counter),
"Total", 1000.0 * INSTR_TIME_GET_DOUBLE(total_time));
}
es->indent--;
}
else
{
ExplainPropertyInteger("Functions", NULL, ji->created_functions, es);
ExplainOpenGroup("Options", "Options", true, es);
ExplainPropertyBool("Inlining", jit_flags & PGJIT_INLINE, es);
ExplainPropertyBool("Optimization", jit_flags & PGJIT_OPT3, es);
ExplainPropertyBool("Expressions", jit_flags & PGJIT_EXPR, es);
ExplainPropertyBool("Deforming", jit_flags & PGJIT_DEFORM, es);
ExplainCloseGroup("Options", "Options", true, es);
if (es->analyze && es->timing)
{
ExplainOpenGroup("Timing", "Timing", true, es);
ExplainOpenGroup("Generation", "Generation", true, es);
ExplainPropertyFloat("Deform", "ms",
1000.0 * INSTR_TIME_GET_DOUBLE(ji->deform_counter),
3, es);
ExplainPropertyFloat("Total", "ms",
1000.0 * INSTR_TIME_GET_DOUBLE(ji->generation_counter),
3, es);
ExplainCloseGroup("Generation", "Generation", true, es);
ExplainPropertyFloat("Inlining", "ms",
1000.0 * INSTR_TIME_GET_DOUBLE(ji->inlining_counter),
3, es);
ExplainPropertyFloat("Optimization", "ms",
1000.0 * INSTR_TIME_GET_DOUBLE(ji->optimization_counter),
3, es);
ExplainPropertyFloat("Emission", "ms",
1000.0 * INSTR_TIME_GET_DOUBLE(ji->emission_counter),
3, es);
ExplainPropertyFloat("Total", "ms",
1000.0 * INSTR_TIME_GET_DOUBLE(total_time),
3, es);
ExplainCloseGroup("Timing", "Timing", true, es);
}
}
ExplainCloseGroup("JIT", "JIT", true, es);
}
/*
* ExplainQueryText -
* add a "Query Text" node that contains the actual text of the query
*
* The caller should have set up the options fields of *es, as well as
* initializing the output buffer es->str.
*
*/
void
ExplainQueryText(ExplainState *es, QueryDesc *queryDesc)
{
if (queryDesc->sourceText)
ExplainPropertyText("Query Text", queryDesc->sourceText, es);
}
/*
* ExplainQueryParameters -
* add a "Query Parameters" node that describes the parameters of the query
*
* The caller should have set up the options fields of *es, as well as
* initializing the output buffer es->str.
*