MySQL 'IS EMPTY'?

pck76

hi all,

Is there a way to check if a column is empty?

I have used

IF column = ''

to get to the same result, but was wondering if there was a better solution?

bradgrafelman

Can you give us a little more information about what you're trying to do? There are various ways to handle this, depending upon what you want to do if the column is empty.

Also, note that there is a difference between a column having the null value and one having an empty (or length 0) string. Which one are you referring to?

pck76

basically I have a field that stores a series of IDs of images (separated by commas)
eg:
400,12,4,12 etc

when the user adds an image into the DB, a new ID is inserted into that field:
-if the field is empty or null, the ID is inserted normally;
-if there's something already in that field, a comma and then the ID are inserted

my query I use is:
UPDATE albums
SET images_list=IF(images_list IS NULL OR images_list = '', '$image_id', CONCAT(images_list,',$image_id'))
WHERE album_id=$album_id

bradgrafelman

Seems like that would work fine, despite the fact that it isn't in normal form. Situations like this can often be avoided if you first normalize your database schema - I would highly recommend reading up on this.

Is there a problem with your current setup (e.g. does that query actually not work or something)?

pck76

no, the query works fine. I was just curious to see whether there was a nicer way to do that..

dagon

pck76;10932808 wrote:
no, the query works fine. I was just curious to see whether there was a nicer way to do that..

it would be nicer to normalize your database