[RFC] - mysql-native rewrite

[simendsjo]

On Monday, 30 September 2013 at 10:34:25 UTC, Kagamin wrote:
> On Sunday, 29 September 2013 at 15:42:10 UTC, simendsjo wrote:
>> the previous, but is this the best way? If we choose to 
>> disallow new commands, that means the user have to explicitly 
>> close a lazy command.
>
> If a command isn't closed as soon as possible, it sounds like a 
> resource leak. If you silently cancel previous query, it can 
> hide logical bug.

Yeah. We need to choose:
1) Starting a new command while another is in flight is an error
    You need to close explicitly if the command isn't finished
2) If another command has been started, it's er error to continue 
iteration of a previous command.

I'm in favor of 1).

>> If using classes, we can safely have several instances for a 
>> command (is this neccessary?)
>
> If you execute the same query repeatedly, there's no need to 
> build the same command every time.

That's what prepared statements are for. If you don't even have 
parameters, it's just 9 bytes (4 of these bytes is an 
undocumented field called iteration_count..).

>> The problem is that MySQL is inconsistent here, and it depends 
>> on if it's a field or a constant. SELECT TRUE is not the same 
>> as SELECT boolean_field.
>> Also, it seems every constant integer is returned as LONGLONG. 
>> But.. The fields include a length property..
>
> Is there some hint it's true and not something else?

Yeah. BOOL is an alias for TINYINT(1). I think it's fair to 
always assume TINYINT(1) is bool. For other types I'm not quite 
sure though.. "SELECT 1" is a LONGLONG, but in D a literal is int 
unless specified otherwise. So there is a mismatch here.