SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 2) ExpressionList (children 1) Function count (children 1) ExpressionList TablesInSelectQuery (children 2) TablesInSelectQueryElement (children 1) TableExpression (children 1) TableIdentifier t1 TablesInSelectQueryElement (children 2) TableExpression (children 1) TableIdentifier t2 TableJoin (children 1) Function equals (children 1) ExpressionList (children 2) Identifier t1.time_alias Identifier t2.time