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Limitations and considerations

You should be aware of the following limitations and considerations when using a Microsoft SQL Server (MS-CDC) source:

  • A secondary Microsoft SQL Server (MS-CDC) node is not supported as a source database.
  • Sparse tables are not supported.
  • Replicating data from indexed views is not supported.
  • Limitations due to the requirement to have MS-CDC enabled on all source tables include:
    • Rename column is not supported
    • Truncate table is not supported
    • WRITETEXT and UPDATETEXT utilities are not supported

    For more information on MS-CDC limitations, see the Microsoft Help.

  • Limitations when capturing DDL operations are as follows:

    • RENAME TABLE will no be captured. When a RENAME TABLE DDL is encountered, the task will continue capturing the changes without renaming the target table. If the task is stopped and resumed of if there is a recoverable error, the table will be suspended to allow the CT table to be manually aligned.
    • Table-level DDLs are not supported. When a table DDL is encountered, the DDL will be transferred to the target and the table will be suspended to allow the CT table to be manually aligned.

  • When running without the db_owner role, the following limitations apply:

    • Capture of DDLs is not supported. To prevent replication errors, you must clear the Capture DDL events check box in the endpoint settings' Advanced tab before running the task.

    • MS-CDC cannot be enabled automatically and should therefore be enabled manually. To prevent replication errors, you must also clear the Enable MS-CDC on all captured tables check box in the endpoint settings' Advanced tab before running the task.

    Information noteSpecial permissions are required for running without the db_owner role. For more information, see Required permissions.
  • Replication of computed columns is supported in Full Load replication tasks only. During change processing, INSERTs to computed columns will appear as NULL on the target and UPDATEs will be ignored.
  • Microsoft Azure SQL Managed Instance partition switching is not supported.

  • The following DML pattern is not supported:

    select <*> into <new_table> from <existing_table>

  • Column-level encryption is not supported.
  • When inserting a value into Microsoft Azure SQL Managed Instance spatial data types (GEOGRAPHY and GEOMETRY), one can either ignore the SRID (Spatial Reference System Identifier) property - in which case the default SRID will be used (0 for GEOMETRY and 4326 for GEOGRAPHY) - or specify a different number. When replicating tables with spatial data types, Qlik Replicate replaces the SRID that was inserted by user with the default SRID.
  • Replicating GEOGRAPHY and GEOMETRY data types is only supported in limited LOB mode.
  • Columnstore indexes are not supported.
  • Memory-optimized tables (using In-Memory OLTP) are not supported.
  • Temporal databases are not supported
  • Delayed durability is not supported
  • Due to an ODBC limitation, no more than 16 columns can be part of a Primary Key.
  • Masked data will be created in the target without masking.

  • OpenLDAP is not supported

  • Replication from databases configured to use ADR (Accelerated Database Recovery) is not supported.

  • Capturing DDL and DML statements within a single transaction is not supported.

  • Replicating a table or schema with an apostrophe (') in its name is not supported.

  • DACPAC replication is not supported.

  • MS-CDC Change Tables with fixed size columns (including NCHAR and CHAR data), the sum of which exceeds 8060 bytes, are not supported.

Non-supported Microsoft SQL Server (MS-CDC) security features

Tables that use the following security features are not supported:

  • Always Encrypted
  • Row-Level Security

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