Question

I have a table containing several fields. The primary key is userId. Currently the user id column contains values ‘1,2,3,4…etc’ like so:

+------+
|userId|
+------+
|  1   |
|  2   |
|  3   |
|  4   | 
...etc

I now want to add new rows ending in a,b,c, like so:

+------+
|userId|
+------+
|  1   |
|  1a  |
|  1b  |
|  1c  | 
|  2   |
|  2a  |
|  2b  |
|  2c  | 
...etc

The new rows should be identical to their parent row, except for the userId. (i.e. 1a,1b & 1c should match 1)

Also I can’t guarantee that there won’t already be a few ‘a’, ‘b’ or ‘c’s in userid column.

Is there a way to write an sql query to do this quickly and easily?

Answer 1

DON’T DO IT you will run into more problems than the one you are trying to solve!

add a new column to store the letter and make the primary key cover the original UserId and this new column.

If you ever just want the userId, you need to split the letter portion off, which will be expensive for your query and be a real pain.