Enabling Schema-level Supplemental Logging

Oracle GoldenGate supports schema-level supplemental logging. Schema-level logging is required for an Oracle source database when using the Oracle GoldenGate DDL replication feature. In all other use cases, it is optional, but then you must use table-level logging instead.

By default, schema-level logging automatically enables unconditional supplemental logging of the primary key and conditional supplemental logging of unique key(s) and foreign key(s) of all tables in a schema. Options enable you to alter the logging as needed.

Note:

Oracle strongly recommends using schema-level logging rather than table-level logging, because it ensures that any new tables added to a schema are captured if they satisfy wildcard specifications. This method is also recommended because any changes to key columns are automatically reflected in the supplemental log data too. For example, if a key changes, there is no need to issue ADD TRANDATA.

Perform the following steps on the source system to enable schema-level supplemental logging.

Start the command line on the source system.
Issue the DBLOGIN command with the alias of a user in the credential store who has privilege to enable schema-level supplemental logging.
```
DBLOGIN USERIDALIAS alias
```
See USERIDALIAS in Reference for Oracle GoldenGate for more information about USERIDALIAS and additional options.
When using ADD SCHEMATRANDATA or ADD TRANDATA on a multitenant database, you can either log directly into the PDB and perform the command. Alternately, if you are logging in at the root level (using a C## user), then you must include the PDB. Issue the ADD SCHEMATRANDATA command for each schema for which you want to capture data changes with Oracle GoldenGate.
```
ADD SCHEMATRANDATA pdb.schema [ALLCOLS | NOSCHEDULINGCOLS]
```
Where:
- Without options, ADD SCHEMATRANDATA schema enables the unconditional supplemental logging on the source system of the primary key and the conditional supplemental logging of all unique key(s) and foreign key(s) of all current and future tables in the given schema. Unconditional logging forces the primary key values to the log whether or not the key was changed in the current operation. Conditional logging logs all of the column values of a foreign or unique key if at least one of them was changed in the current operation. The default is optional to support nonintegrated Replicat but is required to support integrated Replicat because primary key, unique keys, and foreign keys must all be available to the inbound server to compute dependencies. For more information about integrated Replicat, see Deciding Which Replicat Method to Use.
- ALLCOLS can be used to enable the unconditional supplemental logging of all of the columns of a table and applies to all current and future tables in the given schema. Use to support integrated Replicat when the source and target tables have different scheduling columns. (Scheduling columns are the primary key, the unique key, and the foreign key.)
- NOSCHEDULINGCOLS logs only the values of the primary key and all valid unique indexes for existing tables in the schema and new tables added later. This is the minimal required level of schema-level logging and is valid only for Replicat in nonintegrated mode.
In the following example, the command enables default supplemental logging for the hr schema.
```
ADD SCHEMATRANDATA pdbeast.hr ALLCOLS
```
In the following example, the command enables the supplemental logging only for the primary key and valid unique indexes for the HR schema.
```
ADD SCHEMATRANDATA pdbeast.hr NOSCHEDULINGCOLS
```