Re: [boost] sqlpp11: SQL for C++

On 11/11/2013 10:01 AM, Roland Bock wrote:

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On 11/11/2013 7:53 AM, Roland Bock wrote:

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On 2013-11-11 11:27, Rodrigo Madera wrote:

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On Sat, Nov 9, 2013 at 8:03 PM, Roland Bock wrote:

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Hi,

Hello,

Just curious over some points:

Does it support binary transfers over the wire? The library creates template expression trees for the queries. As of now, the tree is serialized and sent to the database connector when you call

db.run(query)

Result rows are currently to be returned from the connector's result object as const char**, see database_api/api.h.

You are kidding ? Is std::vectorstd::string too advanced ? Why C++ programmers are still using C null-terminated strings I will never understand. No kidding. The database client libraries I've used so far are C

On 2013-11-11 15:36, Edward Diener wrote: libraries yielding char**. That is why the current connector interface also uses const char**. BTW: These are typically not null-terminated but are delivered with a size_t* or similar to inform about the length...

It is irrelevant what the database client libraries return. If you are designing an intelligent interface for C++ end-users to use I believe you should create a return of data which is converted into some C++ data type(s). If the returned data is an array of pointers to something lets have it converted, at compile time or run-time, depending on how your library works, into data which a C++ end-user can understand. I do not view 'char **' as anything I want to deal with in modern C++, no matter what it is supposed to mean. With that said the idea of your library looks very interesting. I have always favored an SQL C++ library as one dealing with SQL syntaxes as templated C++ constructs via a DSEL rather than SQL strings of statements. The only downside to your library is that on-the-fly SQL queries based on run-time analysis of database table structure is impossible with such a design, so that I would suggest you also provide a way of generating an SQL string at run-time as a query, with all syntax checking of the string as an end-user responsibility.