SelectWithUnionQuery (children 1) ExpressionList (children 1) SelectQuery (children 2) ExpressionList (children 1) Function quantileTDigest (children 1) ExpressionList (children 1) Identifier x TablesInSelectQuery (children 1) TablesInSelectQueryElement (children 1) TableExpression (children 1) Subquery (children 1) SelectWithUnionQuery (children 1) ExpressionList (children 3) SelectQuery (children 1) ExpressionList (children 1) Literal Float64_-inf (alias x) SelectQuery (children 1) ExpressionList (children 1) Literal Float64_-inf SelectQuery (children 1) ExpressionList (children 1) Literal Float64_-inf