Difference between revisions of "ERROR Column Constraint"

From Recital Documentation Wiki
Jump to: navigation, search
(Products)
 
Line 19: Line 19:
 
==Example==
 
==Example==
 
<code lang="recital">
 
<code lang="recital">
set sql to recital
+
ALTER TABLE customer;
exec sql
+
  ADD COLUMN timeref CHAR(8);
ALTER TABLE customer ADD COLUMN timeref char(8) CHECK validtime(timeref)
+
  CHECK validtime(timeref);
ERROR "Not a valid time string";
+
  ERROR "Not a valid time string"
use customer
+
edit
+
 
</code>
 
</code>
  

Latest revision as of 11:23, 22 December 2009

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

ALTER TABLE customer;
  ADD COLUMN timeref CHAR(8);
  CHECK validtime(timeref);
  ERROR "Not a valid time string"


Products

Recital, Recital Server