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Evaluates a scalar MDX expression and returns either its value or an alternative value (if the value of the expression is null). This function is an InterSystems extension to MDX.

Returned Type

This function returns an expression of the same type that you use with the function.

Syntax and Details



  • MDX_expression is a scalar MDX value (a numeric, string, or logical expression).

  • value_if_null is the value to return if MDX_expression evaluates to null.


The following shows a simple example:

SELECT ISNULL(MEASURES.[%COUNT],"None") ON 0, birthd.decade.MEMBERS ON 1 FROM patients where diagd.chd
 1 1910s                               None
 2 1920s                                  1
 3 1930s                                 12
 4 1940s                                  3
 5 1950s                                 10
 6 1960s                                  3
 7 1970s                               None
 8 1980s                                  1
 9 1990s                               None
10 2000s                               None
11 2010s                               None

See Also

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