From 440e6ff3b023b66ecefa545990d5eeb85bda03ea Mon Sep 17 00:00:00 2001
From: dan <dan@noemail.net>
Date: Mon, 28 Apr 2014 08:49:54 +0000
Subject: [PATCH] Fix an error in estimating of the number of rows visited by a
 range scan.

FossilOrigin-Name: d491de62fce69d93e89f65f7713972f7c2c451f7
---
 manifest       | 14 +++++++-------
 manifest.uuid  |  2 +-
 src/where.c    |  7 ++++++-
 test/cost.test | 27 +++++++++++++++++++++++++++
 4 files changed, 41 insertions(+), 9 deletions(-)

diff --git a/manifest b/manifest
index c32bc38c65..2a1d6b7303 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\san\ssqlite3_stmt_status()\sproblem\scaused\sby\srecent\schangs\son\sthis\sbranch.
-D 2014-04-26T20:21:14.140
+C Fix\san\serror\sin\sestimating\sof\sthe\snumber\sof\srows\svisited\sby\sa\srange\sscan.
+D 2014-04-28T08:49:54.584
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 2ef13430cd359f7b361bb863504e227b25cc7f81
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -291,7 +291,7 @@ F src/vtab.c 21b932841e51ebd7d075e2d0ad1415dce8d2d5fd
 F src/wal.c 76e7fc6de229bea8b30bb2539110f03a494dc3a8
 F src/wal.h df01efe09c5cb8c8e391ff1715cca294f89668a4
 F src/walker.c 11edb74d587bc87b33ca96a5173e3ec1b8389e45
-F src/where.c 488cc018a39d33d97555b5a1e079dfafc32d348a
+F src/where.c d4efd09b7b2c3604e48b015199f5393578ed417b
 F src/whereInt.h 6804c2e5010378568c2bb1350477537755296a46
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/aggerror.test a867e273ef9e3d7919f03ef4f0e8c0d2767944f2
@@ -406,7 +406,7 @@ F test/corruptF.test be9fde98e4c93648f1ba52b74e5318edc8f59fe4
 F test/corruptG.test 1ab3bf97ee7bdba70e0ff3ba2320657df55d1804
 F test/corruptH.test 88ed71a086e13591c917aac6de32750e7c7281cb
 F test/corruptI.test b3e4203d420490fc3d3062711597bc1dea06a789
-F test/cost.test 8a2b846e896c744b940c29e8bab46416a1324717
+F test/cost.test 39d014a90b67169f8482ede8713bff694761d879
 F test/count.test 42a251178e32f617eda33f76236a7f79825a50b5
 F test/coveridxscan.test cdb47d01acc4a634a34fd25abe85189e0d0f1e62
 F test/crash.test fb9dc4a02dcba30d4aa5c2c226f98b220b2b959f
@@ -1162,7 +1162,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh d1a6de74685f360ab718efda6265994b99bbea01
 F tool/win/sqlite.vsix 030f3eeaf2cb811a3692ab9c14d021a75ce41fff
-P c51efaa5d29ee0a91b9e6a83a8dd82530670811a
-R 95df5cff60bc1a7189139d237d77a9d7
+P dee204092421a239f9f60ab83c3a5b3e24d1baea
+R 3b87cec4307de74fea71def903d4f518
 U dan
-Z c6c47e040169e1387f5404e0d25c212f
+Z dce0ef4becf30f1f5b6dab0637076369
diff --git a/manifest.uuid b/manifest.uuid
index 22512678d7..94e48b42ff 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-dee204092421a239f9f60ab83c3a5b3e24d1baea
\ No newline at end of file
+d491de62fce69d93e89f65f7713972f7c2c451f7
\ No newline at end of file
diff --git a/src/where.c b/src/where.c
index 6d924e0782..dd80ab4ccb 100644
--- a/src/where.c
+++ b/src/where.c
@@ -4241,7 +4241,12 @@ static int whereLoopAddBtreeIndex(
     pNew->nOut += nInMul + nIn;
     whereLoopOutputAdjust(pBuilder->pWC, pNew);
     rc = whereLoopInsert(pBuilder, pNew);
-    pNew->nOut = nOutUnadjusted;
+
+    if( pNew->wsFlags & WHERE_COLUMN_RANGE ){
+      pNew->nOut = saved_nOut;
+    }else{
+      pNew->nOut = nOutUnadjusted;
+    }
 
     if( (pNew->wsFlags & WHERE_TOP_LIMIT)==0
      && pNew->u.btree.nEq<(pProbe->nKeyCol + (pProbe->zName!=0))
diff --git a/test/cost.test b/test/cost.test
index 8df32d8ed1..faaa7bdf16 100644
--- a/test/cost.test
+++ b/test/cost.test
@@ -63,6 +63,33 @@ do_eqp_test 3.2 {
   0 0 0 {USE TEMP B-TREE FOR ORDER BY}
 }
 
+#-------------------------------------------------------------------------
+# If there is no likelihood() or stat3 data, SQLite assumes that a closed
+# range scan (e.g. one constrained by "col BETWEEN ? AND ?" constraint)
+# visits 1/16 of the rows in a table.
+#
+# Note: 1/17 =~ 0.058
+# Note: 1/15 =~ 0.067
+#
+reset_db
+do_execsql_test 4.1 {
+  CREATE TABLE t1(a, b);
+  CREATE INDEX i1 ON t1(a);
+  CREATE INDEX i2 ON t1(b);
+}
+do_eqp_test 4.2 {
+  SELECT * FROM t1 WHERE likelihood(a=?, 0.058) AND b BETWEEN ? AND ?;
+} {
+  0 0 0 {SEARCH TABLE t1 USING INDEX i1 (a=?)}
+}
+do_eqp_test 4.3 {
+  SELECT * FROM t1 WHERE likelihood(a=?, 0.067) AND b BETWEEN ? AND ?;
+} {
+  0 0 0 {SEARCH TABLE t1 USING INDEX i2 (b>? AND b<?)}
+}
 
 
 finish_test
+
+
+