Re: [HACKERS] Re: [BUGS] General Bug Report: Bug in optimizer - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: [HACKERS] Re: [BUGS] General Bug Report: Bug in optimizer
Date
Msg-id 199903181853.NAA05775@candle.pha.pa.us
Whole thread Raw
In response to Re: [HACKERS] Re: [BUGS] General Bug Report: Bug in optimizer  (Vadim Mikheev <vadim@krs.ru>)
List pgsql-hackers
> Agreed, this is ok as long as
> 
> vac=> create table table1 (field1 int);
> CREATE
> vac=> insert into table1 values (1);
> INSERT 1583349 1
> vac=> create index i_table1__field1 on table1 (field1);
> CREATE
> vac=> explain select * from table1 where field1 = 1;
> NOTICE:  QUERY PLAN:
> 
> Seq Scan on table1  (cost=1.03 size=1 width=4)
> 
> - SeqScan is used for small tables.
> 
> So, only bug reported is left.

So, yes, I suppose there is an inconsistency there.  Zero-sized
tables(according to vacuum), use index, while tables with some data
don't use index.

How does the system know there is a row in there if you didn't run
vacuum?  That confuses me.


--  Bruce Momjian                        |  http://www.op.net/~candle maillist@candle.pha.pa.us            |  (610)
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