ABAP Keyword Documentation →  ABAP − Reference →  Declarations →  Declaration Statements →  Data Types and Data Objects →  Declaring Data Objects →  DATA →  DATA - TABLE OF →  DATA - tabkeys → 

DATA - key

Short Reference

Syntax

... { [UNIQUE | NON-UNIQUE]
      { {KEY [primary_key [ALIAS key_name] COMPONENTS] comp1 comp2 ...}
      | {DEFAULT KEY} }}
  | { EMPTY KEY } ... .

Alternatives:

1. ... [UNIQUE|NON-UNIQUE] {KEY ...}|{DEFAULT KEY}

2. ... EMPTY KEY

Alternative 1

... [UNIQUE|NON-UNIQUE] {KEY ...}|{DEFAULT KEY}


Effect

Defines the primary table key of an internal table by specifying components or as a standard key. The syntax and semantics of the additions are the same as for the TYPES statement for dedicated table types, with the difference that the primary key of a bound table type must always be specified completely:

If no primary key is specified for DATA using WITH, the addition WITH NON-UNIQUE DEFAULT KEY is added implicitly for standard tables. This gives the table a standard key, which can be empty. In sorted tables and hashed tables, the primary key must be specified explicitly and cannot be empty.

If the name of the primary key primary_key is specified explicitly, the WITH HEADER LINE addition can no longer be specified, even outside the classes.

Note

The declaration of the primary table key as a standard key can be critical for various reasons. It is best to specify key fields explicitly instead. In particular, make sure that the declaration of the standard key is not added by mistake because the key has not been specified explicitly.

Alternative 2

... EMPTY KEY


Effect

Defines an empty primary key in an internal table. This variant is possible for standard tables only. The syntax and semantics are the same as for the statement TYPES.

Notes