Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl Monk, Perl Meditation
 
PerlMonks  

Re^2: Does DBI handle table alias?

by The_Rabbit (Acolyte)
on Oct 06, 2004 at 21:10 UTC ( #397165=note: print w/replies, xml ) Need Help??


in reply to Re: Does DBI handle table alias?
in thread Does DBI handle table alias?

Be careful... you really don't want to create anymore indexes than necessary. Even though you might see a performance increase in your test by building a bunch of extra indexes you might end up causing performance problems in other parts of the system. Remember, that whenever a rows are inserted or deleted there is an additional work that has to be for each index. Just like everything else in programming you have to strike a balance.

Looking at the query you had problems with I am guessing that the only indexes that are going to help are to build an index for user_id and characteristic_id for both tables. Generally, columns that appear in join conditions are good candidates for building an index.

Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Node Status?
node history
Node Type: note [id://397165]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others cooling their heels in the Monastery: (5)
As of 2022-08-12 05:57 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found

    Notices?