Here's a quick tip at sorting VARCHAR type data in mysql database with values in a column.
With the default sort, it would look something like below:
mysql> SELECT column FROM table_name ORDER BY column; column ====== 100 1000 10000 200 2000 20000 ...
Now with "... ORDER BY column+0", I get it sorted right:
mysql> SELECT column FROM table_name ORDER BY column+0; column ====== 100 200 1000 2000 10000 20000 ...
This is a quick fix instead of sorting to CAST operator.