Explore Courses Blog Tutorials Interview Questions
0 votes
in SQL by (20.3k points)

I've written a query to check for users with certain criteria, one being they have an email address.

Our site will allow a user to have or not have an email address.


 SELECT `userID` 

 FROM `users` 

 WHERE `userID` 


         FROM `users_indvSettings`

  WHERE `indvSettingID`=5 AND `optionID`='.$time.')

  AND `email`!=""


Is this the best way to check for an empty field in SQL? I've just tried "IS NOT NULL" and this still returned a user's record without them having an email address.

The query above works but out of curiosity, I wondered if I'm doing it the correct way.

1 Answer

0 votes
by (40.4k points)

To handle both of them, try this:

email > ''

The above code will benefit you from the range access if you have lots of empty email records (both types) in your table.

Note: An empty field can be either an empty string or a NULL.

Related questions

0 votes
1 answer
0 votes
1 answer
asked Dec 31, 2020 in SQL by Appu (6.1k points)
0 votes
1 answer
asked Oct 7, 2019 in SQL by Tech4ever (20.3k points)
0 votes
1 answer
asked Jul 18, 2019 in SQL by Tech4ever (20.3k points)

Browse Categories