I've one table consists of 6 column (xdate, trno, servtype, vendor, customer, usersign).
and 3 vendors table (tktvendor, bookingvendor, insuranceVendor).
i would like to join between the first table and the three vendors table according to field "servtype" value
if servtype=1 i would like to join tktvendor
if servtype=2 i would like to join bookingvendor
if servtype=3 i would like to join insuranceVendor