[Firebird-checkins] CVS: firebird2/src/jrd Optimizer.cpp, 1.78.2.3, 1.78.2.4

[Dmitry Y. <di...@us...>]

Build Version :  T2.5.0.21424 Firebird 2.5 Alpha 1

(writeBuildNum.sh,v 1.21585 2008/11/23 12:48:48 dimitr Exp  )

Update of /cvsroot/firebird/firebird2/src/jrd
In directory fdv4jf1.ch3.sourceforge.com:/tmp/cvs-serv1910

Modified Files:
      Tag: B2_1_Release
	Optimizer.cpp 
Log Message:
A better solution for CORE-2200 (Extremely slow executing a cross join of 3 tables in Firebird 2.X).
This time an optimizer level one.

Index: Optimizer.cpp
===================================================================
RCS file: /cvsroot/firebird/firebird2/src/jrd/Optimizer.cpp,v
retrieving revision 1.78.2.3
retrieving revision 1.78.2.4
diff -b -U3 -r1.78.2.3 -r1.78.2.4
--- Optimizer.cpp	8 Oct 2008 11:48:02 -0000	1.78.2.3
+++ Optimizer.cpp	23 Nov 2008 12:48:47 -0000	1.78.2.4
@@ -2871,8 +2871,7 @@
 		innerStream[i]->stream = streams[i + 1];
 	}
 
-	// Cardinalities are calculated in OPT_compile()
-	//calculateCardinalities();
+	calculateCardinalities();
 	calculateStreamInfo();
 }
 
@@ -2906,19 +2905,21 @@
  *
  **************************************
  *
- *  Get the cardinality for every stream.
+ *  Get the cardinality for every stream (if not estimated yet).
  *
  **************************************/
 
 	for (size_t i = 0; i < innerStreams.getCount(); i++) {		
 		CompilerScratch::csb_repeat* csb_tail = &csb->csb_rpt[innerStreams[i]->stream];
 		fb_assert(csb_tail);
+		if (!csb_tail->csb_cardinality) {
 		jrd_rel* relation = csb_tail->csb_relation;
 		fb_assert(relation);
 		const Format* format = CMP_format(tdbb, csb, (USHORT)innerStreams[i]->stream);
 		fb_assert(format);
 		csb_tail->csb_cardinality = OPT_getRelationCardinality(tdbb, relation, format);
 	}
+	}
 
 }
 
@@ -3123,8 +3124,13 @@
 		if (!innerStreams[i]->used) {
 			remainingStreams++;
 			if (innerStreams[i]->independent()) {
+				if (!optimizer->opt_best_count ||
+					innerStreams[i]->baseCost < optimizer->opt_best_cost)
+				{
 				optimizer->opt_streams[0].opt_best_stream = innerStreams[i]->stream;
 				optimizer->opt_best_count = 1;
+					optimizer->opt_best_cost = innerStreams[i]->baseCost;
+				}
 			}
 		}
 	}