Thread

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

   Zeugswetter Andreas IZ5 <andreas.zeugswetter@telecom.at> — 1998-03-04T10:02:02Z

   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);
   
   
   
   

2. Re: [HACKERS] Feature: output index name in explain ...

   Vadim Mikheev <vadim@sable.krasnoyarsk.su> — 1998-03-25T08:52:04Z

   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
   
   

3. Re: [HACKERS] Feature: output index name in explain ...

   Bruce Momjian <maillist@candle.pha.pa.us> — 1998-03-25T14:46:38Z

   > 
   > 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.
   
   -- 
   Bruce Momjian                          |  830 Blythe Avenue
   maillist@candle.pha.pa.us              |  Drexel Hill, Pennsylvania 19026
     +  If your life is a hard drive,     |  (610) 353-9879(w)
     +  Christ can be your backup.        |  (610) 853-3000(h)