index on numbers not honoured

hi,

an index on a table column of any number type only gets honoured if you
query it like a string, e.g.

create table t1 ( n int2 ) ;

create index t1n on t1 (n) ;

explain select * from t1 where n = 1 ;

-- Seq Scan on t1  (cost=0.00..22.50 rows=10 width=2)

explain select * from t1 where n = '1'  ;

-- Index Scan using t1n on t1  (cost=0.00..8.14 rows=10 width=2)

first i thought this might be an psql client error and tried the same via
jdbc, and look, there it happens again. if i create a PreparedStatemnt and
bind the INT or LONG value with setLong (1,x) the index won't be used in the
select statement. if i bind the value with a setString (1,x+"") command,
then the index is honored correctly. I tested the code against postgres
7.1.3 as well as 7.0.2. this means that i would have to change all my java
code from setLong to setString in order to speed up my apps every time i
query a number. quite ugly!

ilker -)


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