Adabas Column Clause

Function

The Adabas column clause defines the table columns and attributes.

All columns must be unique within a table. Two table attributes may be the same when one attributes is a PRIMARY KEY or UNIQUE table constraint element and the other attribute is an INDEX table index element.

Invocation

The Table Element specification is used with the following statements:

Create Table

Create Table Description

Create Cluster

Create Cluster Description

Syntax

[TABLE COLUMN ELEMENT | TABLE CONSTRAINT ELEMENT | TABLE INDEX ELEMENT]

where:

TABLE COLUMN ELEMENT	Defines a column of a base table. A valid SQL table definition must contain at least one table column definition. See Table Column Element.
TABLE CONSTRAINT ELEMENT	Specifies a UNIQUE, PRIMARY KEY or FOREIGN KEY constraint. See Table Constraint Element.
TABLE INDEX ELEMENT	Specifies an index for the table. Table index element is not part of the ANSI SQL Standard. See Table Index Element.

Description

The definition of foreign keys (part of Table Constraint Element) in the ANSI SQL standard, differs from that of Adabas SQL Gateway Embedded SQL.

A FOREIGN KEY table constraint element may only be specified in the CREATE CLUSTER/CREATE CLUSTER DESCRIPTION statements.