Differences Between Classic and Integrated Capture in Oracle GoldenGate

  

Differences Between Classic and Integrated Capture in Oracle GoldenGate

Classic Capture:

In Classic Capture mode, the Oracle GoldenGate Extract process captures data changes directly from Oracle redo or archive log files. In Oracle RAC environments, a separate ASM user must be created, and the necessary privileges must be granted to access the logs in ASM redo/archive. Alternatively, you can use the TRANLOGOPTIONS DBLOGREADER parameter in the Extract configuration for Classic Capture in a RAC setup.

• Performance: Classic Capture can be CPU-intensive and is generally slower when dealing with complex data types, such as LOBs (Large Objects).
• Multitenant Architecture: Not supported.
• RAC Support: Requires manual specification of threads based on the number of RAC nodes.
• TDE (Transparent Data Encryption): More manual configuration is needed for TDE setups.
• Scalability: Less scalable in larger environments due to its single-threaded processing nature.
• Parallelism: Not supported; it processes redo logs sequentially in a single-threaded manner.
• Registration: No need to register the extract process with the database in Classic Capture.

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Integrated Capture:

In Integrated Capture mode, the database log mining server reads redo logs and captures changes as Logical Change Records (LCRs), which are then accessed by the GoldenGate Extract process. Integrated Capture is closely integrated with Oracle databases and requires no additional steps for RAC environments, as it automatically manages threads and configurations based on the nodes.

• RAC Support: No need to specify threads; it dynamically manages them based on the number of RAC nodes.
• Multitenant Architecture: Fully supported, allowing for replication at the PDB (Pluggable Database) level.
• Registration: The extract process must be registered with the database.
• Scalability: Supports automatic dynamic parallelism, allowing for efficient processing of large volumes of data while ensuring transactional consistency.
• Performance: Integrated Capture is preferred for modern, large-scale, or complex environments due to its superior scalability and performance.

Archivelog Management: Archivelog files will remain until the LogMiner process has processed them. Details can be viewed in the DBA_CAPTURE view.

Memory Allocation: For Integrated Extract, it is essential to allocate memory under the streams_pool_size parameter. The Oracle recommended size for streams_pool_size for each Integrated Extract (IE) process is 1.25 GB.