Comparisons
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Comparisons

Traditional Comparisons

The comparisons of two values of the same type. With cmp they order values, as an ORDER BY does.

OperatorPortable function
=eq(a, b)
<>ne(a, b)
<lt(a, b)
<=le(a, b)
>gt(a, b)
>=ge(a, b)

Ever and Always Comparisons

Whether a temporal value is ever, or always, equal to, different from, less than or greater than a value or another temporal value.

CategoryOperatorPortable function
Ever comparison?=eEqual(a, b)
 ?<>eNotEqual(a, b)
 ?<eLessThan(a, b)
 ?<=eLessEqual(a, b)
 ?>eGreaterThan(a, b)
 ?>=eGreaterEqual(a, b)
Always comparison%=aEqual(a, b)
 %<>aNotEqual(a, b)
 %<aLessThan(a, b)
 %<=aLessEqual(a, b)
 %>aGreaterThan(a, b)
 %>=aGreaterEqual(a, b)

Temporal Comparisons

The comparison of two values at each instant, returning a temporal Boolean.

OperatorPortable function
#=tEqual(a, b)
#<>tNotEqual(a, b)
#<tLessThan(a, b)
#<=tLessEqual(a, b)
#>tGreaterThan(a, b)
#>=tGreaterEqual(a, b)
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