Limitations and considerations

General limitations

The following limitations apply:

• Sybase ASE primary/standby configuration is supported with the publish-and-subscribe model only (i.e. Warm standby/MSA is not supported).

• Only one Qlik Replicate task can be run per SAP Sybase ASE database.
• Rename table is not supported (e.g. sp_rename 'Sales.SalesRegion', 'SalesReg';)
• Rename column is not supported (e.g. sp_rename 'Sales.Sales.Region', 'RegID', 'COLUMN';)
• Zero values located at the end of binary data type strings are truncated when replicated to the target database. For example, 0x0000000000000000000000000100000100000000 in the source table will become 0x00000000000000000000000001000001 in the target table.
• The reorg rebuild index command is not supported.
• Clusters are not supported.
• Materialized views are not supported.
• Merge operations performed during CDC will result in an non-recoverable error.
• The WRITETEXT statement is not supported as it may result in duplicate (or more) inserts on the target.

• The Replicate AR_H_USER header column is not supported for database changes performed in auto-commit mode. For these changes, the header column will be empty.

• Rollback trigger on datarow locked tables is not supported.

• Replicating data with 4-byte emoji characters is not supported.

Limitations when using the RepAgent CDC type

The following limitations are part of the RepAgent Preview release, and are planned to be removed in a future release:

• Partial rollbacks within a transaction (specifically the ROLLBACK TRANSACTION <savepoint_name> command) are not supported. If a command to undo only a portion of a transaction is encountered, the application will roll back the entire transaction to maintain strict data integrity.
• The connection between the Sybase ASE source endpoint (Replicate Server) and the Sybase RepAgent does not support SSL/TLS-based network encryption.
• The RepAgent port is bound on all interfaces. From a practical standpoint, this means that the Sybase endpoint does not validate the host name when accepting connections on that port. You should disable network password encryption in the RepAgent configuration on Sybase ASE server, as described in Prerequisites when using RepAgent CDC. After it is disabled, the Sybase endpoint will be able to validate the RepAgent username and password.
• LOB data type columns will be handled using source-lookup, which might result in slightly degraded performance when replicating LOB data types.