ok this one is fairly simple you would do something like this
SELECT * FROM table WHERE `dec` LIKE '%0'
If you wanted to check that the field had a 0 in there no matter where it is then you can do
SELECT * FROM table WHERE `dec` LIKE '%0%'
The %'s act as wildcards so doing %0 means that the last character must be 0 and doing %0% means that the cheracter 0 can be anywhere in that field.
If you need any further information let me know