Explain EXPLAIN QUERY TREE (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 2)
    ExpressionList (children 1)
     Function plus (children 1)
      ExpressionList (children 2)
       Function minus (children 1)
        ExpressionList (children 2)
         Function sum (children 1)
          ExpressionList (children 1)
           Identifier uint64
         Function multiply (children 1)
          ExpressionList (children 2)
           Literal UInt64_2
           Function count (children 1)
            ExpressionList (children 1)
             Identifier uint64
       Function minus (children 1)
        ExpressionList (children 2)
         Function sum (children 1)
          ExpressionList (children 1)
           Identifier uint64
         Function multiply (children 1)
          ExpressionList (children 2)
           Literal UInt64_3
           Function count (children 1)
            ExpressionList (children 1)
             Identifier uint64
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier test_table
