Explain EXPLAIN SYNTAX (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 3)
    ExpressionList (children 4)
     Identifier x3
     Function minus (children 1)
      ExpressionList (children 2)
       Identifier x3
       Identifier x2
     Identifier x2
     Identifier x1
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier test
    ExpressionList (children 1)
     OrderByElement (children 1)
      Literal UInt64_2