Developer Documentation Library > Data Model > Frequently asked questions > I am getting an "Unknown column" error when I attempt to do an INSERT statement on an RDB database
 
I am getting an "Unknown column" error when I attempt to do an INSERT statement on an RDB database
If I do "INSERT INTO vdata (Respondent.Serial) values(1)", it works fine. However if I try "INSERT INTO vdata (Respondent.Serial, q3) values(2,15)", I get an "Unknown column " message. What could be causing this problem?
It is possible that you connected with the wrong project name. Check the Variables table in the SQL Server database to check the project name for the variable, and if necessary correct the MR Init Project connection property before connecting again.
Alternatively, if the variable exists in the MDM, but does not exist in the RDB database, try running the following statement:
ALTER TABLE vdata ADD q3 Long
See also
INSERT
Relational MR database (RDB) CDSC
Frequently asked questions