We were concerned about the same thing when we had to implement this for Golden Gate but the additional redo generated has been minimal. We still have some outstanding issues around DDL replication for GG. Fairlie Rego Senior Oracle Consultant http://el-caro.blogspot.com/ M: +61 402 792 405 ________________________________ From: "Hameed, Amir" <Amir.Hameed@xxxxxxxxx> To: oracle-l@xxxxxxxxxxxxx Sent: Friday, 23 December 2011 4:57 AM Subject: Additional redo for supplemental logging at table level Hi, I would like to know if anyone has done any testing on how much additional redo is generated if supplemental log groups are created on tables. I know that it will depend on the number of columns in a log group, column size, data type, etc., but I just want to get an idea about generally how much additional information (in terms of %age) is generated for DML statements. Any feedback will be appreciated. Thank you Amir -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l