Doing a count(*) can be really a bad idea

Just learned that doing a count (*) is not that a great idea. People (So do I) often think that it will just pick the row count, but it will do a table scan!

It’s a bad practice to do a count (*) on a really big table.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s