How to Order MySQL VARCHAR Results

Question

In a SELECT statement, I have a varchar column with ORDER BY DESC on it. Examples of data in this column:

1234
987
12-a
13-bh

MySQL would r

Answer 1

The trick part is dealing about the "-": since its optional, you cant directly use SUBSTR in that field (as Marc B pointed out) to get rid of everything after it

So, the trick would be: append an "-" to the value!

Like this:

ORDER BY CAST(SUBSTR(CONCAT(yourfield,'-'), 0, LOCATE('-', CONCAT(yourfield,'-'))) AS UNSIGNED)

Another useful approach is to, instead of using SUBSTR to "remove" everything after the "-", replace it (and all letters) to "0", and THEN use CAST.

Answer 2

The easiest thing to do is this

SELECT *
FROM TBL
ORDER BY VARCHAR_COLUMN * 1;

To see what is happening, just add the column I used for ordering

SELECT *, VARCHAR_COLUMN * 1
FROM TBL
ORDER BY VARCHAR_COLUMN * 1;

Answer 3

...
....
CAST(COL as SIGNED)  DESC