What is cluster tables?
Cluster tables are special types of tables that are available in the SAP Data Dictionary. They are logical tables that are kept as records of the normal SAP tables, which are generally referred to as transparent tables. A major advantage of using cluster tables is that they store data in a compressed format, which reduces the space and burden on the landscape network to retrieve information from these tables.
With cluster tables, functionally dependent data is distributed over many tables and grouped under a cluster table. The key fields in these tables are stored as key fields of cluster tables.
The main characteristics of cluster tables are as follows:
Native SQL cannot be used on these tables.
They cannot be managed directly by database system tools.
Cluster tables are easier to manage because the tables are not created separately like transparent tables in a database.
Functionally dependent data stored in cluster tables can be read together, which reduces access to the database.
Like pool tables, indexes cannot be created on non-key fields. However, primary or other indexes can be created on a group of fields using the
Should be key fields.
Database views, join statements, or append statements cannot be used for these tables.
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