Explain EXPLAIN QUERY TREE (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 2)
    ExpressionList (children 1)
     Function sum (children 1)
      ExpressionList (children 1)
       Function plus (children 1)
        ExpressionList (children 2)
         Identifier uint64
         Literal Float64_2.11
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier test_table
