IsNull

Table of Contents

Overview
Prototype

Example

See also
Related

Returns true (1) if the given value is null, otherwise false (0). This is how to test for missing fields and for the unmatched side of an outer join.

Prototype

Boolean IsNull(String value = null)

Boolean results

Boolean functions return 1 for true and 0 for false. In a WHERE clause compare the result to 1 (or true), for example: WHERE IsLike(Text, 'Cat%') = 1

Example

Selects words that have no matching language.

SELECT w.Text FROM WordList:Word as w OUTER JOIN WordList:Language as l ON l.Id = w.LanguageId WHERE IsNull(l.Name) = 1

See also

Scalar Functions

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Returns the absolute value of a number.

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