Re: index not used in ( varchar = text )

"Gaetano Mendola" <mendola@bigfoot.com> writes:
>> Why would you want to cast that to text, if your field is a varchar?

> Of course that example was a semplification of a real
> situation:
> ..........
> my_login ALIAS FOR $1;

> SELECT *
> FROM user_login
> WHERE login = my_login;

> and $1 is of type TEXT.

So declare it as VARCHAR.  Or cast it to varchar.  You need to get rid
of the datatype ambiguity.  "text = text" is a different operator from
"varchar = varchar".

            regards, tom lane