In Oracle, the USER_REPKEY_COLUMNS dictionary view stores the information about the replication key columns in the tables, which are owned by the current user. During row level replication, replicating key columns determine the columns for comparison. Note that LOB type, collection type, REF type and object type columns cannot be the part of replication key column group. The structure of the view is shown below.
SNAME [VARCHAR2(30)] - Schema name containing the table
ONAME [VARCHAR2(30)] - Table name
COL [VARCHAR2(4000)] - Column name