Mysql query result access by field name

[kdevel]

On Monday, 21 May 2018 at 14:17:23 UTC, Steven Schveighoffer 
wrote:
>>     Data f;
>>     allrows[0].toStruct (f);
>> 
>> I haven't checked this.
>
> This only works if your struct has exactly the same layout as 
> the fields.
>
> So if, for instance, your rows are selected "title", "name", 
> "surname", but your data type orders them name, surname, title, 
> you won't be happy with the result.

Haven't seen this. Then there is no more field-safety than in the 
OP's "assembler" code.

In the other post you wrote

| 1. Use ResultRange instead of the Row interface. This provides
| a couple of ways to use column names, .asAA to get all the data
| in a nice AA format (they are still variants),

The AA format can than be used to fill the struct automatically 
(detecting missing and excess fields) like in this code:

    T toStructX(T) (string[string] a)
    {
       T t;
       bool[string] bookkeep;
       foreach (i, m; t.tupleof) {
          string key = T.tupleof[i].stringof;
          if (key !in a) {
             stderr.writefln ("missing key <%s>", key);
             continue;
          }
          t.tupleof[i] = a[key].to!(typeof (m));
          bookkeep[key] = true;
       }
       foreach (x, y; a)
          if (x !in bookkeep)
             stderr.writefln ("excess key-value pair <%s>:<%s>", 
x, y);
       return t;
    }