Crafty Code

I recently had the need to SELECT some data from MySQL tables and include a “rownum” column on each row. For example, I needed some results that looked like this:

id rownum name
1234 1 Billy
8274 2 Carl
4352 3 Dave

Notice that I cannot use the “id” column because it is auto-generated, and the data is not inserted into the table in the order I am SELECTing it. This type of thing is very easy to achieve in Oracle, which has a built-in “rownum” column that can be added to the SELECT statement. MySQL, unfortunately, does not have a similar construct. So what are we to do?

My first attempt to solve this problem came from a couple of sources like this one:

This solution is quite brilliant. It uses a user defined variable that is incremented each time a row is processed. My query would…

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