NUM(a) is a function (conversion function) that converts the argument a to a numeric value.
NUM can be applied to character strings with the code attribute, date values, time values, timestamp values, and to numeric and Boolean values (BOOLEAN).
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Result of the Function NUM(a) |
a is a character string and can be interpreted as a numeric value |
Corresponding numeric value |
a is a numeric value |
Identical numeric value (unchanged) |
a is a Boolean value |
1, if a=TRUE |
a is a character string that cannot be interpreted as a numeric value; a is a character string that does not have the code attribute ASCII, a is neither a numeric nor a Boolean value. |
Error message |
a is a character string that can be
interpreted as a numeric value outside the range |
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a is the NULL value |
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a is the special NULL value |
Special NULL value |