The following settings are available in "Step 2 - Replication pairs" of the setup wizard.
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- one-by-one : This obtains a unique SCN for each table to replicate from. No locks are required on the tables.
- single-scn : This locks the tables and obtains a single SCN for all tables to replicate from. Locks are required on the tables. See Single SCN Prepare for more information.
- ddl_-only : This does not obtain an SCN to replicate from. This is used when there is no initial data to be copied before the replication starts. The target tables will be empty before replication starts.
- resetlogs : This is used when a complete copy of the source database is made (for example with RMAN) and restored as a target database. When the target database is opened with a resetlogs command, then the SCN is used from the last resetlogs at the target database. It obtains the value from v$database.resetlogs at the target database.
For more information see Creating the Starting Point (data instantiation)
What data copy script to create? (dp_networklink/dp_exp/exp/ddl_file/ddl_run/none)
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For more information see Using Data Pump (and exp/imp)