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Code Issues

Added short-circuit optimization of user-supplied plans. Call find_best() exactly number-of-stream times.

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dimitr 2004-03-07 15:13:53 +00:00
parent 8e43e51609
commit 9e5b3ef1a1
1 changed files with 18 additions and 3 deletions
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21
src/jrd/opt.cpp
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@ -2818,7 +2818,7 @@ static void find_best(TDBB tdbb,
* relationships to form joins. * relationships to form joins.
* *
**************************************/ **************************************/
UCHAR *ptr, *stream_end; UCHAR *ptr;
SET_TDBB(tdbb); SET_TDBB(tdbb);
DEV_BLKCHK(opt, type_opt); DEV_BLKCHK(opt, type_opt);
@ -2835,14 +2835,29 @@ static void find_best(TDBB tdbb,
// code path for SET PLAN as for a normal optimization--it reduces // code path for SET PLAN as for a normal optimization--it reduces
// chances for bugs to be introduced, and forces the person maintaining // chances for bugs to be introduced, and forces the person maintaining
// the optimizer to think about SET PLAN when new features are added --deej // the optimizer to think about SET PLAN when new features are added --deej
if (plan_node && (streams[position + 1] != stream)) { if (plan_node)
{
if (streams[position + 1] == stream)
{
opt->opt_streams[position].opt_best_stream = stream;
++position;
if (position < streams[0])
{
find_best(tdbb, opt, streams[position + 1], position, streams, plan_node,
(double) 0, (double) 1);
}
else
{
opt->opt_best_count = streams[0];
}
}
return; return;
} }
// do some initializations. // do some initializations.
Csb* csb = opt->opt_csb; Csb* csb = opt->opt_csb;
csb->csb_rpt[stream].csb_flags |= csb_active; csb->csb_rpt[stream].csb_flags |= csb_active;
stream_end = &streams[1] + streams[0]; UCHAR* stream_end = &streams[1] + streams[0];
opt->opt_streams[position].opt_stream_number = stream; opt->opt_streams[position].opt_stream_number = stream;
++position; ++position;
Opt::opt_stream* order_end = opt->opt_streams.begin() + position; Opt::opt_stream* order_end = opt->opt_streams.begin() + position;