indexes on a table to
optimise all of your queries. Sometimes this makes the indexes much
larger
than the data itself.
Hope this helps,
Andy
> -Original Message-
> From: Brent Baisley [mailto:[EMAIL PROTECTED]
> Sent: 03 November 2006 16:04
> To: John.H; mysql
> Subj
much larger
than the data itself.
Hope this helps,
Andy
> -Original Message-
> From: Brent Baisley [mailto:[EMAIL PROTECTED]
> Sent: 03 November 2006 16:04
> To: John.H; mysql
> Subject: Re: How many colums should a index contain?
>
> I think you want to create separate
I think you want to create separate indexes. Indexes are basically a sorted list. So a single index on all those fields would sort
the data first by id, then bid, then title,...
If id is unique, then there is absolutely no reason to add other fields to the index. Think of a compound index as a f
John.H wrote:
but why when I do a query with 'explain' ,it shows that the
'possible_keys' is null or primary rather than the index I just create
Please always CC the list - you will get much faster responses and
others will be able to offer their input as well.
Post the query, the explain
John.H wrote:
I have two tables and I must do :
select `id`,`bid`,`title`,`link`,`bname` from table1 where `bid` in
( ...this is a subquery in table2 )
should I create a index (`id`,`bid`,`title`,`link`,`bname`) so that my
query
will take less time
or should a index contain so many colums?
I
