For accurate detection of conflicts, all records must have a unique, not-null identifier. If possible, create a primary key. If that is not possible, use a unique key or create a substitute key with a KEYCOLS option of the MAP and TABLE parameters. In the absence of a unique identifier, Oracle GoldenGate uses all of the columns that are valid in a WHERE clause, but this will degrade performance if the table contains numerous columns.

To maintain data integrity and prevent errors, the following must be true of the key that you use for any given table:

• contain the same columns in all of the databases where that table resides.

• contain the same values in each set of corresponding rows across the databases.