SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 2) ExpressionList (children 1) Function sumKahan (children 1) ExpressionList (children 1) Function toFloat64 (children 1) ExpressionList (children 1) Identifier number TablesInSelectQuery (children 1) TablesInSelectQueryElement (children 1) TableExpression (children 1) Function numbers (children 1) ExpressionList (children 1) Literal UInt64_10