ERROR Column Constraint

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Purpose

Column constraint to define an error message to be displayed when a validation check fails


Syntax

ERROR <expC>


See Also

ALTER TABLE, CONSTRAINTS, CREATE TABLE


Description

A constraint is used to define rules that help to provide data integrity. Column constraints are specific to the column name specified. You must have ALTER privilege on the table. The table will be locked for EXCLUSIVE use during the operation.

The ERROR column constraint is used to define an error message to be displayed when a validation check fails. The <expC> is a character string of up to 80 characters.


Example

set sql to recital
exec sql
ALTER TABLE customer ADD COLUMN timeref char(8) CHECK validtime(timeref)
ERROR "Not a valid time string";
use customer
edit


Products

Recital, Recital Server