List:MySQL++« Previous MessageNext Message »
From:Warren Young Date:June 25 2005 1:46am
Subject:Re: Early testers of v2.0 wanted
View as plain text  
Warren Young wrote:
>  See the new simple2 example for the proper way to process
> a "use" query.

That example demonstrates good style for the "no exceptions" case, but 
the situation wasn't so good for the "with exceptions" case.  In the 
earlier v2.0 code, you'd get a BadQuery exception when you hit the end 
of the result set.  Since the query is not in fact bad, I've created a 
new EndOfResults exception to signal "fetch_row() walked off the end of 
the result set".  I've also added a new example, usequery.cpp, which 
demonstrates it.

I considered returning v2.0 to v1.7-like behavior here, and simply 
returning an empty row at the end of the result set.  I rejected it 
because the promise always has been that objects pass their exception 
state on to their children.  It didn't happen in v1.7, but this is a 
bug, not a feature worth keeping.  If you want the v1.7 behavior, use 
the new NoExceptions facility on the ResUse object before you start 
walking through the result set, but after you assign the return value of 
Query::use() to it.

Along these lines, I'm going to create more new exceptions.  BadQuery is 
severely overloaded; it's pretty much a generic exception at this point. 
  I'm going to make it for bad queries only in v2.0.  To avoid problems 
when migrating between v1.7 and v2.0, all of your MySQL++ exception 
catch blocks should include one for std::exception, which will act as a 
"catch all" for those not caught by a more specific catch block.  Most 
of the examples have a block like this in v1.7, so if you've emulated 
them, you won't need to change anything.
Early testers of v2.0 wantedWarren Young18 Jun
  • Re: Early testers of v2.0 wantedErwin19 Jun
    • Re: Early testers of v2.0 wantedWarren Young20 Jun
      • Re: Early testers of v2.0 wantedWarren Young25 Jun