Explain EXPLAIN QUERY TREE (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 4)
    ExpressionList (children 1)
     Function sum (alias j) (children 1)
      ExpressionList (children 1)
       Function plus (children 1)
        ExpressionList (children 2)
         Literal UInt64_1 (alias m)
         Identifier uint64 (alias n)
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier test_table
    Function and (children 1)
     ExpressionList (children 2)
      Function greater (children 1)
       ExpressionList (children 2)
        Identifier m
        Literal UInt64_0
      Function greater (children 1)
       ExpressionList (children 2)
        Identifier n
        Literal UInt64_0
    Function greater (children 1)
     ExpressionList (children 2)
      Identifier j
      Literal UInt64_0
