Re: Why the difference in plans ?

Josh,

On 6-Mar-08, at 12:26 PM, Josh Berkus wrote:

> Dave,
>
>> Below I have two almost identical queries.  Strangely enough the one
>> that uses the index is slower ???
>
> My first guess would be that records are highly correlated by DOB
> and not at
> all by name.  However, it would help if you supplied both the index
> definitions and what changed between the two queries to cause the
> index to be
> used.

Indexes:
     "user_profile_pkey" PRIMARY KEY, btree (uid) CLUSTER
     "user_profile_name_idx" UNIQUE, btree (name varchar_pattern_ops)
     "user_profile_name_key" UNIQUE, btree (name)
     "user_profile_uploadcode_key" UNIQUE, btree (uploadcode)
     "user_profile_active_idx" btree (isactive)
     "user_profile_areacode_index" btree (areacode)
     "user_profile_gender_idx" btree (gender)

and nothing changed between runs.

Dave
>
>
> --
> Josh Berkus
> PostgreSQL @ Sun
> San Francisco
>
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