Thread: Feature: output index name in explain ...

Since I wanted to know it, I extended explain to output the used (only the
first)
index on IndexScan.
An explain with this patch applied says:

template1=> explain select * from pg_class where oid=1;
NOTICE:  QUERY PLAN:
Index Scan using pg_class_oid_index on pg_class  (cost=2.03 size=1 width=74)
EXPLAIN

Does somebody want to add it to CVS please ?
Andreas

--- src/backend/commands/explain.c    Tue Mar  3 21:10:34 1998

+++
src/backend/commands/explain.c.orig    Thu Feb 26 05:30:58 1998

@@ -23,6
+23,7 @@

 #include <parser/parse_node.h>

 #include <optimizer/planner.h>


#include <access/xact.h>

+#include <utils/relcache.h>



 typedef struct
ExplainState

 {

@@ -117,6 +118,8 @@

 static void

 explain_outNode(StringInfo
str, Plan *plan, int indent, ExplainState *es)

 {

+    List
*l;

+    Relation    relation;

     char       *pname;

     char
buf[1000];

     int            i;

@@ -184,8 +187,12 @@


appendStringInfo(str, pname);

     switch (nodeTag(plan))

     {

-
case T_SeqScan:

         case T_IndexScan:

+
appendStringInfo(str, " using ");

+            l = ((IndexScan *)
plan)->indxid;

+            relation =
RelationIdCacheGetRelation((int) lfirst(l));

+
appendStringInfo(str, (RelationGetRelationName(relation))->data);

+
case T_SeqScan:

             if (((Scan *) plan)->scanrelid > 0)


{

                 RangeTblEntry *rte = nth(((Scan *)
plan)->scanrelid - 1, es->rtable);

Zeugswetter Andreas SARZ wrote:
>
> Since I wanted to know it, I extended explain to output the used (only the
> first)
> index on IndexScan.
> An explain with this patch applied says:
>
> template1=> explain select * from pg_class where oid=1;
> NOTICE:  QUERY PLAN:
> Index Scan using pg_class_oid_index on pg_class  (cost=2.03 size=1 width=74)

I like this. Any objections ?

Vadim

>
> Zeugswetter Andreas SARZ wrote:
> >
> > Since I wanted to know it, I extended explain to output the used (only the
> > first)
> > index on IndexScan.
> > An explain with this patch applied says:
> >
> > template1=> explain select * from pg_class where oid=1;
> > NOTICE:  QUERY PLAN:
> > Index Scan using pg_class_oid_index on pg_class  (cost=2.03 size=1 width=74)
>
> I like this. Any objections ?

Love it.

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