Table

• Table : is a Table structure and table data used to organize information in the form of rows and columns.
• Tables are defined in Data dictionary and their Physical storage is in Database.So DDIC table and DB Table are Same.
• Types of Table.

1. Transparent Table.
2. Pool Table.
3. Cluster Table.

Transparent Table.

1. Contain a single table.Used to store master  data.
2. It has a one-to-one relationship with a table in the database.
3. For each transparent table there is one associated table in the database.
4. The database table has the same name, same number of fields and the fields have the same names.
5. There is only a single table.
6. Single table can have one or more primary key.
7. Secondary indexes can be created.
8. They can be accessed using open and native SQL.

Use :They are used to hold master data eg : Table vendors (LFA1) or table of Customer( KNA1).

Pool Table.

1. They are used to hold a large number of very small tables( Stores customizing data or system data ).
2. It has a many-to one relationship with a table in the database.
3. Its is stored with other pooled tables in a single table called Table Pool in the database.
4. The database table has different name , different number of fields and fields have different names.
5. Table pools contain more tables than table clusters.
6. Primary key of each table does not begin with same fields or fields.
7. Secondary indexes cannot be created.
8. They can be accessed using open SQL only.

Use : They reduce the amount of database resources needed when many small tables have to be opened at the same time.

Cluster Table.

1. They are used to hold data from a few number of large tables (Stores system data).
2. It has a many-to-one relationship with table in the database.
3. Many cluster table are stored in a single table in the database called a table cluster.
4. The database table has different name , different numbers of fields and fields have different names.
5. Contains less tables than table pools.
6. Primary key of each table begins with same fields or fields.
7. Secondary indexes cannot be created.
8. They can be accessed using open SQL only.

Use : They would be used when the tables have primary key in common data in these tables are all accesses simultaneously.

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