How to give select permission on particular table to user

Hi all,
in aix environment , i want to give only select permission on particular table to a user.

i tried to creat new user and add

# The following three lines have been added by UDB DB2.
if [ -f /home/db2inst1/sqllib/db2profile ]; then
. /home/db2inst1/sqllib/db2profile
fi
but it giving complete permission, so i remoted above lines from testuser again

from db2inst1,run following command , it is successful

db2 "grant connect on database to user testuser"

DB20000I The SQL command completed successfully.

but db2 is not working in testuser

what to do to run db2 in testuser, where i am missing??

anybody can help me ???