SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 1) ExpressionList (children 1) Function dateDiff (children 1) ExpressionList (children 4) Literal \'year\' Function toDate (children 1) ExpressionList (children 2) Literal \'2015-08-18\' Literal \'UTC\' Function toDate32 (children 1) ExpressionList (children 2) Literal \'2016-08-18\' Literal \'UTC\' Literal \'UTC\'