MySql: Compare 2 strings which are numbers?

Question

I have a column in my table, it holds values such as 100012345. The column is varchar. Now I want to compare this to similiar values in a where:

... where my         


        

Answer 1

You can cast the value to an integer:

CAST(myColumn AS INTEGER)

Answer 2

You don't have to cast strings into integers to compare, mysql does it automatically.

http://dev.mysql.com/doc/refman/5.0/en/comparison-operators.html

Answer 3

Have you tried to do it normally, like this:

... where myColumn > 100012345

That should work!, mysql automatically casts a string to number when it's in the context of a number operation. In the same way it casts a number to string if it's used in a string context. See the examples in the type conversion docs:

To cast a string to a numeric value in numeric context, you normally do not have to do anything other than to use the string value as though it were a number:

mysql> SELECT 1+'1';
       -> 2

If you use a string in an arithmetic operation, it is converted to a floating-point number during expression evaluation.

If you use a number in string context, the number automatically is converted to a string:

mysql> SELECT CONCAT('hello you ',2);
        -> 'hello you 2'

Answer 4

select * from your_table
where cast(your_column as signed) = 100012345