What do you mean by storage group (STOGROUP)?

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Storage group is a storage path where data can be stored. A table space can also be assigned to storage group.

In IBM Db2, a storage group, commonly referred to as STOGROUP, is a logical grouping of storage volumes. It is used to simplify database administration by providing a way to manage the physical storage of database objects.

A storage group allows you to specify a set of storage volumes that can be used to store table spaces and indexes. This grouping helps in organizing and managing the physical storage of database data. When you define a table space or an index, you can associate it with a particular storage group, and Db2 will then allocate space for the objects within the specified storage group.

Key points about storage groups (STOGROUP) in Db2:

  1. Logical Grouping: STOGROUP is a logical grouping and does not necessarily represent a physical grouping of storage devices.
  2. Simplified Administration: By associating table spaces and indexes with a storage group, you can simplify administration tasks such as backup, restore, and reorganization.
  3. Storage Volume Allocation: The storage volumes within a storage group can be automatically allocated by Db2 when new data needs to be stored. This helps in optimizing disk space usage.
  4. Improved Performance: When a storage group is associated with a table space or an index, Db2 can allocate space from any volume within that group, potentially improving I/O performance by distributing data across multiple volumes.

Here is an example of how you might define a storage group in Db2:

CREATE STOGROUP my_stogroup


ON '/path/to/volume1'
'/path/to/volume2'
'/path/to/volume3';

This example creates a storage group named my_stogroup and associates it with three storage volumes.

In summary, a storage group in Db2 is a logical container for storage volumes, providing a convenient way to manage and organize the physical storage of database objects.