Performance check using COPY commands

Hi All,

 

     I have a problem in updating a table using copy commands. To brief you about the table, the table has 6 columns in which it has one column for a sequence number which increments by one on each entry. There is a constraint check for one of the columns. I am copying data in all the 6 columns (including the sequence number of my own) in the table, since the version of postgres i am using is 7.2 i cant copy only those columns i want to instead I should copy all the columns present in the table. Now the problem is that the copy is taking a lot of time to bulk copy the data, and I have no idea why is that so. Is it because of the sequence number or some thing else. Since copying data into other table which has relatively more columns is taking much much lesser time may be in the ratio 1:15 times i guess. Can some body suggest me what is happening there?

 

Regards

Sid