Question

Basically I want to query a database and modify the values of one column based on the contents of another.

Here’s my idea of how it would work:

IF Column 'Town'  IS NOT NULL then Column 'Sign-up type' = 1 else = 0

The logic is, i’ve added a new column into the DB that will store whether a quick or full sign up has been made.

Quick = 0, Full = 1. Default is 0 = Quick.

I’ve managed to implement the change on the two registration forms that feed the DB, but I need to append the historical data to backwards fill the data.

Because the quick sign up only collects name, and email, those entries do not contain data in the ‘Town’ field which is a required field in a full sign up.

So i’m using that as a reference point to select all the entries that DO have (NOT NULL?) data in order to enter ‘1’ (representing ‘Full’) into ‘Signup Type’ column.

I hope I’m making sense! I only have a basic understanding of MySQL but I’m willing to learn, it’s sometimes hard trying to explain what I want to do when I’m unclear of the correct jargon!!

Answer 1

UPDATE yourTable SET signupType = IF(Town IS NULL, 1, 0);

Note this will update all data, you may want to limit this to historical data (by the sounds of things this should be fine however).