Difference between revisions of "KEY Table Constraint"

Revision as of 04:17, 25 October 2011

Purpose

Table constraint to define an index key

Syntax

KEY [<cTagName>] (column1[, column2,...])

See Also

ALTER TABLE, CONSTRAINTS, CREATE TABLE

Description

A constraint is used to define rules that help to provide data integrity. TABLE constraints apply to table-based operations. You must have ALTER privilege on the table. The table will be locked for EXCLUSIVE use during the operation.

The KEY table constraint is used to define an index key. The index is built on the column or columns specified and given the name as defined in <cTagName>. The INDEX table constraint can be used in the same way.

Example

CREATE TABLE contact;
  (LastName char(25), FirstName char(25),;
  KEY FullName (LastName, FirstName))

Products

Recital, Recital Server