T-SQL query can use any of three clauses—ON, WHERE, and HAVING—for specifying logical expressions that SQL Server uses as filters. The three filters play different roles, but sometimes it can be difficult to know which clause you should specify a logical expression in. Most T-SQL programmers know when to specify a logical expression in the HAVING clause because SQL Server applies the HAVING clause after grouping the input data. But confusion around when to use the ON and WHERE clauses ...