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.
The Table Element specification is used with the following statements:
Defines a column of a base table. A valid SQL table definition must contain at least one table column definition. See Table Column Element. |
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Specifies a UNIQUE, PRIMARY KEY or FOREIGN KEY constraint. See Table Constraint Element. |
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Specifies an index for the table. Table index element is not part of the ANSI SQL Standard. See Table Index Element. |
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.