Re: Case Insensitive

Am 28.03.19 um 09:33 schrieb Sameer Kumar:
>
> test=*# select * from emp where ename = 'aaa';
>   eid | ename
> -----+-------
>     1 | aaa
>     2 | AAA
> (2 rows)
>
>
>
> Ummm... Will it use an index (a BTree index)?
>

test=# explain select * from emp where ename = 'aaa';
                     QUERY PLAN
-----------------------------------------------------
 Seq Scan on emp  (cost=0.00..25.88 rows=6 width=36)
   Filter: (ename = 'aaa'::citext)
(2 rows)

test=*# set enable_seqscan to off;
SET
test=*# explain select * from emp where ename = 'aaa';
                               QUERY PLAN
------------------------------------------------------------------------
 Seq Scan on emp  (cost=10000000000.00..10000000025.88 rows=6 width=36)
   Filter: (ename = 'aaa'::citext)
(2 rows)

test=*# create index emp_ename on emp(ename);
CREATE INDEX
test=*# explain select * from emp where ename = 'aaa';
                              QUERY PLAN
----------------------------------------------------------------------
 Index Scan using emp_ename on emp  (cost=0.13..8.14 rows=1 width=36)
   Index Cond: (ename = 'aaa'::citext)
(2 rows)

test=*#

Regards, Andreas

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