I am under the impression that a primary key field is automically as a unique index. It seems to be correct after I verify it
with the page http://www.commandprompt.com/ppbook/index.lxp?lxpwrap=c13329%2ehtm#CREATINGANINDEX
Thanks for bringing up the question.
12/5/2002 12:35:36 PM, Tomasz Myrta <jasiek(at)klaster(dot)net> wrote:
>Vernon Wu wrote:
>> The personid is a foreign key in the block table, and the the userid
>> is the key of the profile table. So, both are indexed
>> by nature (if I don't make a mistake).
>What kind of nature? Did you create indexes for these fields? Postgres
>doesn't create indexes by itself - even if field is a primary key. You
>have to do it on your own. I think also, that Postgres doesn't use index
>for tables having less then 200 rows - sequence scan is faster.
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