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Thread: Which query is good - IN or OR

Which query is good - IN or OR

From
AI Rumman
Date:
A simple query I can write in any of the following two ways:

1. 
Select col1
from table
where col2 in ('A','B');

2.
Select col1
from table
where
 col2 = 'A'
or  col2 = 'B'

Here IN condition may be more than two.
I need to know which one is good for good performance.

Any idea please.

Re: Which query is good - IN or OR

From
Pavel Stehule
Date:
Hello

2010/12/9 AI Rumman <rummandba@gmail.com>:
> A simple query I can write in any of the following two ways:
> 1.
> Select col1
> from table
> where col2 in ('A','B');
> 2.
> Select col1
> from table
> where
>  col2 = 'A'
> or  col2 = 'B'
> Here IN condition may be more than two.
> I need to know which one is good for good performance.
> Any idea please.

It depends on real use case. In almost all cases these queries are almost same.

Regards

Pavel Stehule