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AdministeringIn addition to administering the database server, you can tune performance, replicate data, and archive data.
Enterprise ReplicationThe HCL OneDB™ Enterprise Replication Guide describes the concepts of data replication using HCL® OneDB® Enterprise Replication, including how to design your replication system, as well as administer and manage data replication throughout your enterprise.
Planning and designing for Enterprise ReplicationBefore you set up your replication system, plan how to include Enterprise Replication into your database server environment, design your database schema by following Enterprise Replication requirements, and then design your replication system between database servers.
Schema design for Enterprise ReplicationWhen you design the database and tables for replication, you must follow the requirements and restrictions for Enterprise Replication.
Out-of-Row Data

Out-of-Row Data

Enterprise Replication collects out-of-row data for transmission after the user transaction has committed. Due to activity on the replicated row, the data might not exist at the time Enterprise Replication collects it for replication. In such cases, Enterprise Replication normally applies a NULL on the target system, unless the data is a smart large object. Therefore, you should avoid placing a NOT NULL constraint on any replicated column that includes out-of-row data.

If a column has smart large objects and the smart large object data does not exist when Enterprise Replication collects it for replication, then Enterprise Replication creates smart large objects with no data and zero size.