This subsection discusses the coding rules for a conditional expression specified in the stream.filterCondition parameter.
Specify a conditional expression in the following format:
'('column-name comparison-operator constant')'[{AND | OR}'('column-name comparison-operator constant')' |
To combine multiple comparison operations, use AND or OR to join the expressions. You can specify a maximum of ten expressions.
The following describes the elements of a conditional expression.
Comparison operator | Usage example | Meaning |
---|---|---|
<= | A <= B | A is equal to or less than B |
>= | A >= B | A is equal to or greater than B |
< | A < B | A is less than B |
> | A > B | A is greater than B |
= | A = B | A is equal to B |
!= | A != B | A is not equal to B |
The following shows an example of a conditional expression:
stream.filterCondition=(xxx='abc')AND(zzz>18)AND(zzz<60) |
This example retains only those tuples whose column xxx is abc and column zzz is greater than 18 and smaller than 60.