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 multiply (children 1)
          ExpressionList (children 2)
           Literal UInt64_2
           Function count (children 1)
            ExpressionList (children 1)
             Identifier decimal32
         Function sum (children 1)
          ExpressionList (children 1)
           Identifier decimal32
       Function minus (children 1)
        ExpressionList (children 2)
         Function multiply (children 1)
          ExpressionList (children 2)
           Literal UInt64_3
           Function count (children 1)
            ExpressionList (children 1)
             Identifier decimal32
         Function sum (children 1)
          ExpressionList (children 1)
           Identifier decimal32
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier test_table
