{ measure_column [ { condition | expr }[ , { condition | expr } ...] ]
| aggregate_function 
        { [ { condition | expr }[ , { condition | expr } ...] ]
        | [ single_column_for_loop [, single_column_for_loop] ... ]
        | [ multi_column_for_loop ]
        }
| analytic_function
}

Note: The outside square brackets shown in boldface type are part of the syntax.
      In this case, they do not represent optionality.