Mysql - why use unsigned columns?
 

I have been looking at many hacks, and notice that some tables have their columns unsigned, and others dont. I know that when a column is unsigned, it starts counting at 0, as opposed to negatives... but is that simply all that should determine assigning a column as unsigned??? the fact that there is simply no need for negative intergers in my scripts?

???

UNSIGNED is normally used with AUTO_INCREMENT, (which is used to create a sequence of unique identifiers), because the values of AUTO_INCREMENT are always postive integers.

I see... thanks Danny!

If you don't use negative number then it doubles the maximum value the column can hold, e.g. for a 2 byte integer, signed max = 32767, unsigned = 65535.

thanks for that info as well Paul