Key Category (SAP Library

Key Category

The key category defines whether the internal table defined by the table type may only contain keys with a unique key or whether the key may have duplicates.

The following key categories may be defined:

unique: This table type may only contain records with a unique key.

non-unique: A table with this table type may also contain records that do not have different keys for the table type.

not specified: The key category is unique or non-unique. This defines a generic table type.

Only certain combinations of access mode and key category are allowed. These are listed in the following table.

Access Mode	Key category
Not specified	Not specified
Index table	Not specified
Standard table	Non-unique
Sorted table	Unique, non-unique or not specified
Hash table	Unique

There is one exception: If the key of a standard table or hash table is not specified, you have to select key category not specified.