Difference between revisions of "ERROR Column Constraint"
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==Example== | ==Example== | ||
<code lang="recital"> | <code lang="recital"> | ||
| − | + | ALTER TABLE customer; | |
| − | + | ADD COLUMN timeref CHAR(8); | |
| − | ALTER TABLE customer ADD COLUMN timeref | + | CHECK validtime(timeref); |
| − | ERROR "Not a valid time string" | + | ERROR "Not a valid time string" |
| − | + | ||
| − | + | ||
</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
