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You can remove a column from a data source, even if its data load has been run in the past, by using this procedure. The procedure to make this change to an existing data source has two main parts:

  • Alter the table definition in the target table using TQL.


  1. Log in to the Linux shell using SSH.
  2. Launch TQL.

     $ tql
  3. Designate the database you’ll be working in:

     TQL> use <database_name>;


  5. Issue the command to remove the column from the table using this syntax:

     TQL> ALTER TABLE <schema>.<table>
          DROP COLUMN <column>;

    For example, to drop the column “account_id” from the table “account” in the schema “foodmart”:

     TQL> ALTER TABLE foodmart.account
          DROP COLUMN account_id;



     TQL> SCRIPT TABLE <table>;


  7. Create a new data source.. Be sure to choose the correct columns to match the new target table columns definitions. When you reach the step about editing the generated schema DDL, paste in the DDL that was output by the SCRIPT TABLE command.