Important We are integrating BMC AMI LOBMaster technology into the BMC AMI Reorg product and discontinuing BMC AMI LOBMaster as a separate product. For the latest integrated documentation, see BMC AMI Reorg for Db2 13.1.

Large object (LOB) components

(BMC.DB2.SPE2407)

This topic describes the basic LOB components.

There are three types of LOBs, all of which BMC AMI Reorg AUX YES handles:

  • Character large objects (CLOBs)
  • Binary large objects (BLOBs)
  • Double-byte character large objects (DBCLOBs)

The following table describes the components associated with LOBs:

Related topics

Getting-started-with-BMC-AMI-Reorg

Benefits-of-BMC-AMI-Reorg-AUX-YES


LOB components

LOB entity

Description

Base table space

A table space that contains at least one LOB column

LOB column

A ROW column in the base table space that identifies the LOB

Each LOB in a row can be NULL or contain a version number.

ID

A unique ID that is assigned to each LOB

The ID is a 19-byte value that consists of the following parts:

  • Row ID - an identifier that is unique to a table space row
  • Version number - an identifier that indicates the last update to the LOB

LOB index

A unique index on the ID field that indexes the LOB table rather than the base table

LOB table space (or auxiliary table space)

The Db2 data set that contains the LOB data

Each LOB table space contains the LOB data for a specific column in the base table space. If a base table space contains three LOB columns, three separate LOB table spaces exist.

LOB

A collection of data that has been inserted into a Db2 row in a LOB-defined column

A LOB ranges in size from 1 byte to 2 GB.

 

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