RECALCULATE Column Constraint

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Purpose

Column constraint to force recalculation of calculated columns when a column's value changes

Syntax

RECALCULATE

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 RECALCULATE column constraint is used to force recalculation of calculated columns when a column's value changes. Any column which forms part of the calculation expression of a CALCULATED column must have the RECALCULATE column constraint set.

Example

ALTER TABLE customer;
  ALTER COLUMN available CALCULATED limit-balance;
  ALTER COLUMN limit RECALCULATE;
  ALTER COLUMN balance RECALCULATE