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-rw-r--r--src/backend/commands/explain.c172
1 files changed, 135 insertions, 37 deletions
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 19df98531c5..25b9f13fe20 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -5,12 +5,14 @@
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994-5, Regents of the University of California
*
- * $Header: /cvsroot/pgsql/src/backend/commands/explain.c,v 1.73 2002/03/22 02:56:31 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/commands/explain.c,v 1.74 2002/03/24 04:31:07 tgl Exp $
*
*/
#include "postgres.h"
+#include "access/heapam.h"
+#include "catalog/pg_type.h"
#include "commands/explain.h"
#include "executor/instrument.h"
#include "lib/stringinfo.h"
@@ -22,6 +24,7 @@
#include "rewrite/rewriteHandler.h"
#include "tcop/pquery.h"
#include "utils/builtins.h"
+#include "utils/guc.h"
#include "utils/lsyscache.h"
#include "utils/relcache.h"
@@ -35,9 +38,15 @@ typedef struct ExplainState
List *rtable; /* range table */
} ExplainState;
+typedef struct TextOutputState
+{
+ TupleDesc tupdesc;
+ DestReceiver *destfunc;
+} TextOutputState;
+
static StringInfo Explain_PlanToString(Plan *plan, ExplainState *es);
-static void ExplainOneQuery(Query *query, bool verbose, bool analyze,
- CommandDest dest);
+static void ExplainOneQuery(Query *query, ExplainStmt *stmt,
+ TextOutputState *tstate);
static void explain_outNode(StringInfo str, Plan *plan, Plan *outer_plan,
int indent, ExplainState *es);
static void show_scan_qual(List *qual, bool is_or_qual, const char *qlabel,
@@ -48,6 +57,10 @@ static void show_upper_qual(List *qual, const char *qlabel,
const char *inner_name, int inner_varno, Plan *inner_plan,
StringInfo str, int indent, ExplainState *es);
static Node *make_ors_ands_explicit(List *orclauses);
+static TextOutputState *begin_text_output(CommandDest dest, char *title);
+static void do_text_output(TextOutputState *tstate, char *aline);
+static void do_text_output_multiline(TextOutputState *tstate, char *text);
+static void end_text_output(TextOutputState *tstate);
/* Convert a null string pointer into "<>" */
#define stringStringInfo(s) (((s) == NULL) ? "<>" : (s))
@@ -55,42 +68,47 @@ static Node *make_ors_ands_explicit(List *orclauses);
/*
* ExplainQuery -
- * print out the execution plan for a given query
+ * execute an EXPLAIN command
*/
void
-ExplainQuery(Query *query, bool verbose, bool analyze, CommandDest dest)
+ExplainQuery(ExplainStmt *stmt, CommandDest dest)
{
+ Query *query = stmt->query;
+ TextOutputState *tstate;
List *rewritten;
List *l;
- /* rewriter and planner may not work in aborted state? */
- if (IsAbortedTransactionBlockState())
- {
- elog(WARNING, "(transaction aborted): %s",
- "queries ignored until END");
- return;
- }
+ tstate = begin_text_output(dest, "QUERY PLAN");
- /* rewriter will not cope with utility statements */
if (query->commandType == CMD_UTILITY)
{
- elog(NOTICE, "Utility statements have no plan structure");
- return;
+ /* rewriter will not cope with utility statements */
+ do_text_output(tstate, "Utility statements have no plan structure");
}
-
- /* Rewrite through rule system */
- rewritten = QueryRewrite(query);
-
- /* In the case of an INSTEAD NOTHING, tell at least that */
- if (rewritten == NIL)
+ else
{
- elog(NOTICE, "Query rewrites to nothing");
- return;
+ /* Rewrite through rule system */
+ rewritten = QueryRewrite(query);
+
+ if (rewritten == NIL)
+ {
+ /* In the case of an INSTEAD NOTHING, tell at least that */
+ do_text_output(tstate, "Query rewrites to nothing");
+ }
+ else
+ {
+ /* Explain every plan */
+ foreach(l, rewritten)
+ {
+ ExplainOneQuery(lfirst(l), stmt, tstate);
+ /* put a blank line between plans */
+ if (lnext(l) != NIL)
+ do_text_output(tstate, "");
+ }
+ }
}
- /* Explain every plan */
- foreach(l, rewritten)
- ExplainOneQuery(lfirst(l), verbose, analyze, dest);
+ end_text_output(tstate);
}
/*
@@ -98,7 +116,7 @@ ExplainQuery(Query *query, bool verbose, bool analyze, CommandDest dest)
* print out the execution plan for one query
*/
static void
-ExplainOneQuery(Query *query, bool verbose, bool analyze, CommandDest dest)
+ExplainOneQuery(Query *query, ExplainStmt *stmt, TextOutputState *tstate)
{
Plan *plan;
ExplainState *es;
@@ -108,9 +126,9 @@ ExplainOneQuery(Query *query, bool verbose, bool analyze, CommandDest dest)
if (query->commandType == CMD_UTILITY)
{
if (query->utilityStmt && IsA(query->utilityStmt, NotifyStmt))
- elog(INFO, "QUERY PLAN:\n\nNOTIFY\n");
+ do_text_output(tstate, "NOTIFY");
else
- elog(INFO, "QUERY PLAN:\n\nUTILITY\n");
+ do_text_output(tstate, "UTILITY");
return;
}
@@ -122,7 +140,7 @@ ExplainOneQuery(Query *query, bool verbose, bool analyze, CommandDest dest)
return;
/* Execute the plan for statistics if asked for */
- if (analyze)
+ if (stmt->analyze)
{
struct timeval starttime;
struct timeval endtime;
@@ -154,7 +172,7 @@ ExplainOneQuery(Query *query, bool verbose, bool analyze, CommandDest dest)
es->printCost = true; /* default */
- if (verbose)
+ if (stmt->verbose)
es->printNodes = true;
es->rtable = query->rtable;
@@ -162,12 +180,20 @@ ExplainOneQuery(Query *query, bool verbose, bool analyze, CommandDest dest)
if (es->printNodes)
{
char *s;
+ char *f;
s = nodeToString(plan);
if (s)
{
- elog(INFO, "QUERY DUMP:\n\n%s", s);
+ if (Explain_pretty_print)
+ f = pretty_format_node_dump(s);
+ else
+ f = format_node_dump(s);
pfree(s);
+ do_text_output_multiline(tstate, f);
+ pfree(f);
+ if (es->printCost)
+ do_text_output(tstate, ""); /* separator line */
}
}
@@ -176,17 +202,14 @@ ExplainOneQuery(Query *query, bool verbose, bool analyze, CommandDest dest)
StringInfo str;
str = Explain_PlanToString(plan, es);
- if (analyze)
+ if (stmt->analyze)
appendStringInfo(str, "Total runtime: %.2f msec\n",
1000.0 * totaltime);
- elog(INFO, "QUERY PLAN:\n\n%s", str->data);
+ do_text_output_multiline(tstate, str->data);
pfree(str->data);
pfree(str);
}
- if (es->printNodes)
- pprint(plan); /* display in postmaster log file */
-
pfree(es);
}
@@ -709,3 +732,78 @@ make_ors_ands_explicit(List *orclauses)
return (Node *) make_orclause(args);
}
}
+
+
+/*
+ * Functions for sending text to the frontend (or other specified destination)
+ * as though it is a SELECT result.
+ *
+ * We tell the frontend that the table structure is a single TEXT column.
+ */
+
+static TextOutputState *
+begin_text_output(CommandDest dest, char *title)
+{
+ TextOutputState *tstate;
+ TupleDesc tupdesc;
+
+ tstate = (TextOutputState *) palloc(sizeof(TextOutputState));
+
+ /* need a tuple descriptor representing a single TEXT column */
+ tupdesc = CreateTemplateTupleDesc(1);
+ TupleDescInitEntry(tupdesc, (AttrNumber) 1, title,
+ TEXTOID, -1, 0, false);
+
+ tstate->tupdesc = tupdesc;
+ tstate->destfunc = DestToFunction(dest);
+
+ (*tstate->destfunc->setup) (tstate->destfunc, (int) CMD_SELECT,
+ NULL, tupdesc);
+
+ return tstate;
+}
+
+/* write a single line of text */
+static void
+do_text_output(TextOutputState *tstate, char *aline)
+{
+ HeapTuple tuple;
+ Datum values[1];
+ char nulls[1];
+
+ /* form a tuple and send it to the receiver */
+ values[0] = DirectFunctionCall1(textin, CStringGetDatum(aline));
+ nulls[0] = ' ';
+ tuple = heap_formtuple(tstate->tupdesc, values, nulls);
+ (*tstate->destfunc->receiveTuple) (tuple,
+ tstate->tupdesc,
+ tstate->destfunc);
+ pfree(DatumGetPointer(values[0]));
+ heap_freetuple(tuple);
+}
+
+/* write a chunk of text, breaking at newline characters */
+/* NB: scribbles on its input! */
+static void
+do_text_output_multiline(TextOutputState *tstate, char *text)
+{
+ while (*text)
+ {
+ char *eol;
+
+ eol = strchr(text, '\n');
+ if (eol)
+ *eol++ = '\0';
+ else
+ eol = text + strlen(text);
+ do_text_output(tstate, text);
+ text = eol;
+ }
+}
+
+static void
+end_text_output(TextOutputState *tstate)
+{
+ (*tstate->destfunc->cleanup) (tstate->destfunc);
+ pfree(tstate);
+}
generated by cgit v1.2.3 (git 2.46.0) at 2025-08-16 13:19:24 +0000