Dear Gramunt,

Thank you for your help and advice. I have already tried the command but it is still not work. Got an error message "Cannot find data type C" from AERROR(). Command is "?sqlexec(mDBConn, "alter table table1 alter column field1 C(3) NULL")". I have also tried to add a new column using the following command "alter table table1 add column field2 C(20) NOT NULL", another error message showed "Incorrect syntax near the keyword 'column'". I'm using VFP 6.0 and SP5.

Thank you for your help ....

Best Regards,

Justy Chow