WHEN

The WHEN evaluates a condition. Then, based on that evaluation, evaluates another condition and returns "true" or "false".

Syntax:

WHEN ( single-condition-expression , single-condition-expression [ , single-condition-expression ] )

Meaning:

WHEN ( condition1 , condition2 [ , condition3 ] )

Returns:

"True" or "false"

The following statements summarize how the WHEN function works:

• Returns "true" if condition1 and condition2 both evaluate to "true".
• Returns "true" if condition1 evaluates to "false" and there is no condition3 or if condition1 evaluates to "false" and condition3 evaluates to "true".
• Returns "false" if condition1 evaluates to "true" and condition2 evaluates to "false".
• Returns "false" if both condition1 and condition3 evaluate to "false".

Evaluation of the three arguments:

Examples

• WHEN (ABSENT(CatalogueField), ABSENT (QuantityField))

  Returns "true" when CatalogueField and QuantityField are both absent

• WHEN (PRESENT(ShipDate), PRESENT(InStock), PRESENT(BackOrderDate ))

  Returns "false" when ShipDate and BackOrderDate are both absent