BCV5

In Focus

Can BCV5 copy between different Db2 versions or function levels?
Yes, BCV5 can copy into target Db2 subsystems that have either the same or a higher version or function level than the source Db2 subsystem. BCV5 will automatically run the REPAIR utility in order to adjust the target Db2 catalog so that it properly reflects, among other things, the row format and RBA format of the target page sets at the end of the copy process.

Can BCV5 copy simple tablespaces?
Starting with Db2 V9, it is not possible to create new simple tablespaces anymore. However, BCV5 is still able to copy existing simple tablespace into newly created objects without using Unload/Load. All simple tablespaces are converted to segmented tablespaces on the fly during the copy process. Since the conversion process may change the locations of rows in the tablespace, BCV5 will automatically run the REBUILD INDEX utility on all indexes that are defined on the target tablespace at the end of the copy.

Can BCV5 copy only the DDL?
Yes. The copy process of BCV5 consists of six jobs. In order to copy only the DDL structure of a database to a target it is possible to submit only the first two stages. These two stages extract the DDL from the source and create the involved object in the target. After these two stages you have the same database structure like in the source, but the objects are empty.

Does BCV5 require advanced copy services like Flashcopy™?
No, hardware based copy services are not required. BCV5 has its own integrated copy facility, which is able to copy Db2 VSAM datasets directly. It copies datasets in parallel and also takes care of translating OBIDs and other internal values.
Hardware based copy services like Flashcopy™ or Snapshot™ can be integrated into the BCV5 copy process, but doing so requires additional post processing of the target VSAM clusters by BCV5. Therefore, it is recommended to use the built-in copy facility.

Does BCV5 copy real time statistics?
Yes. BVC5 copies the real time statistics for all involved objects (tablespaces, indexes, LOB and XML tablespaces) from the source catalog to the target catalog. Having accurate real time statistics is important because Db2 utilities such as REORG TABLESPACE or REBUILD INDEX can use the real time statistics to calculate the sizes of required sort work datasets. Inaccurate real time statistics in the target environment may cause these utilities to overallocate or underallocate sort work space.

Does BCV5 copy the RUNSTATS information?
Yes. BCV5 extracts RUNSTATS information from the source catalog and inserts it directly into the target catalog. This enables the Db2 optimizer to find the most efficient access path for your applications that access the target environment.

Does BCV5 ensure the compatibility of source and target?
Yes. When you copy into an existing target environment, BCV5 performs a compatibility check before the actual copy is done. This compatibility check ensures that the objects of the source and target have compatible attributes. Each tablespace and index is checked separately. Objects that are compatible are copied directly on VSAM level. Otherwise, BCV5 can either switch to an Unload/Load based copy process for incompatible objects, or drop and recreate the target objects so that a direct VSAM copy becomes possible. No matter which method BCV5 chooses, there is no need to change the JCL or take any other manual action.

Does BCV5 handle identity columns and sequences?
Yes. BCV5 will automatically update the high value of all involved identity columns and sequence objects so that the next INSERT operation in the target environment will get a new unused number. BCV5 also updates implicit sequences for XML columns.

Does BCV5 handle OBID translation?
Yes. BCV5 automatically determines the DBID, PSID and OBID values of your source and target objects and translates all occurrences of these IDs while copying the page sets. No manual action is required.

How does BCV5 handle additional target indexes?
If the target environment already exists and it has indexes that do not exist in the source, BCV5 will automatically rebuild them at the end of the copy process.

How does BCV5 handle LOB and XML tablespaces?
Assuming that the structures of the base tablespaces and base tables are compatible, BCV5 copies LOB and XML tablespaces directly on VSAM level. If Unload/Load is required, the LOB or XML data will be unloaded into either a PDS-E or a VBS data set, depending on the settings. When copying uncompressed XML tablespaces into a different Db2 subsystem, BCV5 will automatically translate the XML string IDs. Note: Compressed XML tablespaces can only be copied into a different Db2 subsystem by switching to Unload/Load.

How is a BCV5 copy process organized?
Each copy process is represented by a BCV5 task. A BCV5 task contains information about which objects participate in the copy process, how objects should be renamed, and the processing options.
BCV5 tasks can be created using either the ISPF interface, the graphical interface, or the batch interface. Depending on the task type, the BCV5 process has between 4 and 7 jobs (the number of jobs is independent from the number of objects that a task processes).

Is it possible to integrate BCV5 into a scheduler?
Yes. The complete BCV5 copy process consists of 4 to 7 jobs, depending on the task type. Once the JCL has been generated, it does not change, even if objects are added, changed, or removed in the source or target environment. This makes it really easy to integrate the BCV5 copy process into a scheduler to make regular copies of your Db2 data.

Are the source objects accessible during the copy process?
This depends on the task type you are using. If you are using a normal copy task, leaving the source objects available for read/write access for the duration of the copy process is an option, however, consistency in the target is only guaranteed if the source objects are set to read-only during the copy. In an in-flight copy task, the source objects always remain available for read/write access, and BCV5 will always guarantee consistency in the target.

Which copy rates can we expect?
Experience shows that copy speeds between 1 and 1.5 TB per hour can be expected. The actual copy speed that you can achieve depends on the environment and the workload that is running at the same time as the BCV5 jobs.

Why is BCV5 so fast?
BCV5 has an integrated copy program which is optimized for high speed Db2 copies. It copies tablespaces (regular, LOB and XML) and indexes directly on VSAM level. This eliminates the need to use Unload/Load to copy the data, which work on row level and are therefore much slower. The BCV5 copy program uses parallel processing and automatic workload balancing, which reduces the required elapsed time even more. Catalog statistics and RTS are also copied directly so that no additional utilities need to be executed on the target environment.