Filtering with the WHERE Clause
After you have aggregated a fact to form the foundations of a metric, you can use MAQL syntax to add filters to your metric definition. Filters are optional features that can be used to narrow the set of data from which a metric is computed. With logical expressions, you can also combine two or more filters within a single metric definition.
The basic syntax for filters uses the word WHERE to introduce the filter expression:
SELECT ... WHERE ...
This section will explore several types of syntax for customizing metric filters:
- Special operators for defining filters
SELECT Revenues WHERE Year = 2006
- Time macros for filtering for floating time periods:
SELECT Payment WHERE Date = THIS – 1
- Logical expressions for combining filters
SELECT Revenues WHERE Year = 2006 AND Month = 5