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 Supplemental logging is not the default behaviour of the oracle database. It has to be enabled manually after the database is created. It can be enabled at two levels

1.  DATABASE LEVEL
2. TABLE LEVEL

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The following SQL is run by Dbvisit Replicate to turn on supplemental logging

SQL> alter database add supplemental log data;

If DDL is enabled, then the following is run

SQL> alter database add supplemental log data (primary key) columns;

For each table to be replicated the following SQL is run

SQL> alter table '||owner||'.'||table_name||' add supplemental log data (primary key) columns;

The supplemental log groups created by Dbvisit Replicate start with a G and then a random hex string: G575B4B0CC2E511E2A20CB8ADB3813

ALTER TABLE <table_name> ADD SUPPLEMENTAL LOG GROUP <log_grp1> 
(Column1,....,Column33) ALWAYS; 

ALTER TABLE <table_name> ADD SUPPLEMENTAL LOG GROUP <log_grp2> 
(Column34,....,Column66) ALWAYS; 
 
ALTER TABLE <table_name> ADD SUPPLEMENTAL LOG GROUP <log_grp3> 
(Column67,....,Column99) ALWAYS;

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Verify supplemental logging

To check and monitor what supplemental logging has been turned on, the following query can be run

SQL> SELECT supplemental_log_data_min MIN, 

supplemental_log_data_pk PK, 

supplemental_log_data_ui UI, 

supplemental_log_data_fk FK,

supplemental_log_data_all "ALL" 

FROM v$database;

Modifying supplemental log behaviour

Please see variable _ADD_SUPLOG in Internal Variables on the default supplemental log behaviour and how to modify this. 

How Dbvisit Replicate works with supplemental logging

Here is an example of a conditional user-defined supplemental log group for jobcode and sdate columns where ID is primary key. 

ALTER TABLE AVI.SAMPLE
ADD SUPPLEMENTAL LOG GROUP sample_jobcode (ID,JOBCODE,SDATE) ALWAYS;

The ALWAYS keyword is required to create an unconditional supplemental log group to ensure the column(s) in the filter condition are always logged in the redo log, regardless of whether they appear in the DML statement.