Re: Strange result from query::execute()?

Kevin Regan wrote:
> Should the following have different results?

It's a known weakness in the library's current design.  If we added an 
overload for execute(const std::string&), we'd run into ambiguous 
conversion problems.  This Wishlist item is on point, if you'd like to 
tackle it:

      Currently, all overloads for Query's execute(), store()
      and use() methods eventually call the const char*
      version, which does the actual work of executing the query.
      This rules out query strings with embedded nulls, as you're
      likely to get with BLOB columns.  Also, it means MySQL++
      must scan the string for length in a few places.  The C API
      isn't limited in this way if you use mysql_real_query(),
      but you need an accurate length value to call it.  We could
      get that length with binary data if the end of the call
      chain were a std::string overload, but we can't do that
      easily because each of these functions has a version taking
      a SQLString (a subclass of std:string) for template queries.

      One way around this is to add a parallel set of functions
      (e.g. do_execute(), or execute_(), or some such) that take
      a single std::string, which are the new terminus of the call
      chain.  Reimplement const char* versions in terms of these.

      Another way is to rename the template query versions (e.g. to
      execute_tq()) to avoid the overload conflict.  With that
      done, we can use C API functions like mysql_real_query(),
      which can take binary data.

      Yet another way is to add a length parameter to the call
      chain end functions.

      And finally, we may be able to co-opt the first template
      query version of each of these functions, as it takes a
      single SQLString.

If done right, the change can go into v2.1, as it wouldn't break the 
ABI.  Otherwise, it'll have to wait for v3.0.

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