Filter Operator

A filter operator specifies how a property value is compared with a reference value, for instance equals, does not equal, contains, or is greater than.

Operators group by data type: text operators such as equals, contains and starts with; numeric or date operators such as greater than and between; and existence operators such as is set and is not set. Two places go wrong regularly. The first is negation combined with missing values, because a condition like does not equal Tehran also drops rows where the property was never recorded, so its result is not the same as everything minus Tehran and the tool's handling of empty values has to be checked. The second is contains, which matches on substrings, so a short term matches far more than intended.