To identify lag in Replicat process and modify columns of a table:
Suspend activity on the source database for all tables that are linked to Oracle GoldenGate.
Start Admin Client.
Run this command for the Replicat group:
INFO REPLICAT group
On the Checkpoint Lag line, verify whether there is any Replicat lag. If needed, continue to issue INFO REPLICAT until lag is zero, which indicates that all of the data in the trail has been processed.
Stop the Replicat group.
STOP REPLICAT group
Perform the table modifications on the target databases.
Start the Replicat process.
START REPLICAT group
Allow user activity to resume on all of the source tables that are linked to Oracle GoldenGate.