Page 1 of 1

Table: how big is big? (in columns...)

Posted: Sun May 26, 2002 2:12 pm
by Gath
I saw some info around (in the MySQL manual there's something about it), but i can get a straihgt answer...

How big is big?

I mean, does a table with around 150-170 columns considered big?
Should i break it in several different tables?

Up-side is that in more then half the pages only 1 query would occour.
In several tables, several queries would occour...

Any info on this?

Thanks.

Posted: Sun May 26, 2002 5:21 pm
by mydimension
it really depends on what you are doing with the information. for mw i try to make my tables small using foreign keys to cross link information. this in turn gives me fewer columns in return for a few more tables (depends on the application). newbienetwork has a good databse design tutorial that could help you out.

do i guess in answer to your question: there is no limit really. i guess a good rule of thumb would be: its too big if you don't want to writee the long qury to get the information you need.

Posted: Sun May 26, 2002 6:05 pm
by jason
It works like this: When you start to question whether a table is too big or not...it probably is. If you feel your design will lead to a large table, examine a different design. Their is always another way to do things.

Posted: Sun May 26, 2002 7:56 pm
by volka
it's like the question 'is it fast?'. The question should be 'is it fast enough?'

Posted: Tue May 28, 2002 11:59 am
by Gath
Ok, thanks...


And just a quicky:
does a query (SELECT) increase/decrease speed if one uses the * (all), or about only half of the fields?

Thanks.

Posted: Tue May 28, 2002 5:47 pm
by mydimension
using the * (all) selector is the slowest but the easiest. if you don't need to select all columns then don't and only select the ones you need