ASA SQL User's Guide
  Adding, Changing, and Deleting Data

Changing data using INSERT

You can use the ON EXISTING clause of the INSERT statement to update existing rows in a table (based on primary key lookup) with new values. This clause can only be used on tables that have a primary key. Attempting to use this clause on tables without primary keys or on proxy tables generates a syntax error.

Specifying the ON EXISTING clause causes the server to do a primary key lookup for each input row. If the corresponding row does not exist, it inserts the new row. For rows already existing in the table, you can choose to:

• generate an error for duplicate key values. This is the default behavior if the ON EXISTING clause is not specified.

• silently ignore the input row, without generating any errors.

• update the existing row with the values in the input row

For more information, see the INSERT statement.