| Subject | Question about index selectivity |
|---|---|
| Author | Zd |
| Post date | 2010-11-15T12:55:23Z |
Hello!
I have many tables containing integers which can either be 1 or 0. (true or false)
My question is: if more than 90% of a field's data in some of these tables is going to be 0 and only 10% is 1, is it worth creating an index for that particular field? I suppose that having an additional index will slow down inserts, but is it going to speed up my SELECTs?
Is it worth creating indices with a low selectivity?
Thank you!
[Non-text portions of this message have been removed]
I have many tables containing integers which can either be 1 or 0. (true or false)
My question is: if more than 90% of a field's data in some of these tables is going to be 0 and only 10% is 1, is it worth creating an index for that particular field? I suppose that having an additional index will slow down inserts, but is it going to speed up my SELECTs?
Is it worth creating indices with a low selectivity?
Thank you!
[Non-text portions of this message have been removed]