Change column type?

[Alberto Moreno]

Hi people.

I use phpMyAdmin to access and manage my mysql 5.0.x server. I have some tables that have different value type, example:

Table #1
CargaID bigint(20) unsigned NO PRI NULL auto_increment

Table #2
CargaID int(11) NO PRI NULL

Table #3
CargaID int(10) unsigned NO MUL NULL

This is the key between this tables, I would like to change this column in all the tables to:

CargaID int(20) unsigned

To make this possible, can I just pickup the value with phpMyAdmin and change it? Or exist other way to do this? Could I lost or corrupt my data?

Can I just change from bigint to int or vice versa?

Thanks!!!