Index: src/analyze.c
==================================================================
--- src/analyze.c
+++ src/analyze.c
@@ -524,11 +524,11 @@
 /*
 ** Copy the contents of sample *pNew into the p->a[] array. If necessary,
 ** remove the least desirable sample from p->a[] to make room.
 */
 static void sampleInsert(Stat4Accum *p, Stat4Sample *pNew, int nEqZero){
-  Stat4Sample *pSample;
+  Stat4Sample *pSample = 0;
   int i;
 
   assert( IsStat4 || nEqZero==0 );
 
 #ifdef SQLITE_ENABLE_STAT4
@@ -567,10 +567,11 @@
     tRowcnt *anLt = pMin->anLt;
     tRowcnt *anDLt = pMin->anDLt;
     sampleClear(p->db, pMin);
     memmove(pMin, &pMin[1], sizeof(p->a[0])*(p->nSample-p->iMin-1));
     pSample = &p->a[p->nSample-1];
+    pSample->nRowid = 0;
     pSample->anEq = anEq;
     pSample->anDLt = anDLt;
     pSample->anLt = anLt;
     p->nSample = p->mxSample-1;
   }

Index: src/vdbemem.c
==================================================================
--- src/vdbemem.c
+++ src/vdbemem.c
@@ -1029,11 +1029,11 @@
 
     if( pRec==0 ){
       Index *pIdx = p->pIdx;      /* Index being probed */
       int nByte;                  /* Bytes of space to allocate */
       int i;                      /* Counter variable */
-      int nCol = pIdx->nKeyCol+1; /* Number of index columns including rowid */
+      int nCol = pIdx->nColumn;   /* Number of index columns including rowid */
   
       nByte = sizeof(Mem) * nCol + sizeof(UnpackedRecord);
       pRec = (UnpackedRecord*)sqlite3DbMallocZero(db, nByte);
       if( pRec ){
         pRec->pKeyInfo = sqlite3IndexKeyinfo(p->pParse, pIdx);

ADDED   test/index7.test
Index: test/index7.test
==================================================================
--- test/index7.test
+++ test/index7.test
@@ -0,0 +1,251 @@
+# 2013-11-04
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#***********************************************************************
+#
+# Test cases for partial indices in WITHOUT ROWID tables
+#
+
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+ifcapable !vtab {
+  finish_test
+  return
+}
+
+load_static_extension db wholenumber;
+do_test index7-1.1 {
+  # Able to parse and manage partial indices
+  execsql {
+    CREATE TABLE t1(a,b,c PRIMARY KEY) WITHOUT rowid;
+    CREATE INDEX t1a ON t1(a) WHERE a IS NOT NULL;
+    CREATE INDEX t1b ON t1(b) WHERE b>10;
+    CREATE VIRTUAL TABLE nums USING wholenumber;
+    INSERT INTO t1(a,b,c)
+       SELECT CASE WHEN value%3!=0 THEN value END, value, value
+         FROM nums WHERE value<=20;
+    SELECT count(a), count(b) FROM t1;
+    PRAGMA integrity_check;
+  }
+} {14 20 ok}
+
+# Make sure the count(*) optimization works correctly with
+# partial indices.  Ticket [a5c8ed66cae16243be6] 2013-10-03.
+#
+do_execsql_test index7-1.1.1 {
+  SELECT count(*) FROM t1;
+} {20}
+
+# Error conditions during parsing...
+#
+do_test index7-1.2 {
+  catchsql {
+    CREATE INDEX bad1 ON t1(a,b) WHERE x IS NOT NULL;
+  }
+} {1 {no such column: x}}
+do_test index7-1.3 {
+  catchsql {
+    CREATE INDEX bad1 ON t1(a,b) WHERE EXISTS(SELECT * FROM t1);
+  }
+} {1 {subqueries prohibited in partial index WHERE clauses}}
+do_test index7-1.4 {
+  catchsql {
+    CREATE INDEX bad1 ON t1(a,b) WHERE a!=?1;
+  }
+} {1 {parameters prohibited in partial index WHERE clauses}}
+do_test index7-1.5 {
+  catchsql {
+    CREATE INDEX bad1 ON t1(a,b) WHERE a!=random();
+  }
+} {1 {functions prohibited in partial index WHERE clauses}}
+do_test index7-1.6 {
+  catchsql {
+    CREATE INDEX bad1 ON t1(a,b) WHERE a NOT LIKE 'abc%';
+  }
+} {1 {functions prohibited in partial index WHERE clauses}}
+
+do_test index7-1.10 {
+  execsql {
+    ANALYZE;
+    SELECT idx, stat FROM sqlite_stat1 ORDER BY idx;
+    PRAGMA integrity_check;
+  }
+} {t1 {20 1} t1a {14 1} t1b {10 1} ok}
+
+# STAT1 shows the partial indices have a reduced number of
+# rows.
+#
+do_test index7-1.11 {
+  execsql {
+    UPDATE t1 SET a=b;
+    ANALYZE;
+    SELECT idx, stat FROM sqlite_stat1 ORDER BY idx;
+    PRAGMA integrity_check;
+  }
+} {t1 {20 1} t1a {20 1} t1b {10 1} ok}
+
+do_test index7-1.11b {
+  execsql {
+    UPDATE t1 SET a=NULL WHERE b%3!=0;
+    UPDATE t1 SET b=b+100;
+    ANALYZE;
+    SELECT idx, stat FROM sqlite_stat1 ORDER BY idx;
+    PRAGMA integrity_check;
+  }
+} {t1 {20 1} t1a {6 1} t1b {20 1} ok}
+
+do_test index7-1.12 {
+  execsql {
+    UPDATE t1 SET a=CASE WHEN b%3!=0 THEN b END;
+    UPDATE t1 SET b=b-100;
+    ANALYZE;
+    SELECT idx, stat FROM sqlite_stat1 ORDER BY idx;
+    PRAGMA integrity_check;
+  }
+} {t1 {20 1} t1a {13 1} t1b {10 1} ok}
+
+do_test index7-1.13 {
+  execsql {
+    DELETE FROM t1 WHERE b BETWEEN 8 AND 12;
+    ANALYZE;
+    SELECT idx, stat FROM sqlite_stat1 ORDER BY idx;
+    PRAGMA integrity_check;
+  }
+} {t1 {15 1} t1a {10 1} t1b {8 1} ok}
+
+do_test index7-1.14 {
+  execsql {
+    REINDEX;
+    ANALYZE;
+    SELECT idx, stat FROM sqlite_stat1 ORDER BY idx;
+    PRAGMA integrity_check;
+  }
+} {t1 {15 1} t1a {10 1} t1b {8 1} ok}
+
+do_test index7-1.15 {
+  execsql {
+    CREATE INDEX t1c ON t1(c);
+    ANALYZE;
+    SELECT idx, stat FROM sqlite_stat1 ORDER BY idx;
+    PRAGMA integrity_check;
+  }
+} {t1 {15 1} t1a {10 1} t1b {8 1} t1c {15 1} ok}
+
+# Queries use partial indices as appropriate times.
+#
+do_test index7-2.1 {
+  execsql {
+    CREATE TABLE t2(a,b PRIMARY KEY) without rowid;
+    INSERT INTO t2(a,b) SELECT value, value FROM nums WHERE value<1000;
+    UPDATE t2 SET a=NULL WHERE b%5==0;
+    CREATE INDEX t2a1 ON t2(a) WHERE a IS NOT NULL;
+    SELECT count(*) FROM t2 WHERE a IS NOT NULL;
+  }
+} {800}
+do_test index7-2.2 {
+  execsql {
+    EXPLAIN QUERY PLAN
+    SELECT * FROM t2 WHERE a=5;
+  }
+} {/.* TABLE t2 USING COVERING INDEX t2a1 .*/}
+ifcapable stat4||stat3 {
+  do_test index7-2.3stat4 {
+    execsql {
+      EXPLAIN QUERY PLAN
+      SELECT * FROM t2 WHERE a IS NOT NULL;
+    }
+  } {/.* TABLE t2 USING COVERING INDEX t2a1 .*/}
+} else {
+  do_test index7-2.3stat4 {
+    execsql {
+      EXPLAIN QUERY PLAN
+      SELECT * FROM t2 WHERE a IS NOT NULL AND a>0;
+    }
+  } {/.* TABLE t2 USING COVERING INDEX t2a1 .*/}
+}
+do_test index7-2.4 {
+  execsql {
+    EXPLAIN QUERY PLAN
+    SELECT * FROM t2 WHERE a IS NULL;
+  }
+} {~/.*INDEX t2a1.*/}
+
+do_execsql_test index7-2.101 {
+  DROP INDEX t2a1;
+  UPDATE t2 SET a=b, b=b+10000;
+  SELECT b FROM t2 WHERE a=15;
+} {10015}
+do_execsql_test index7-2.102 {
+  CREATE INDEX t2a2 ON t2(a) WHERE a<100 OR a>200;
+  SELECT b FROM t2 WHERE a=15;
+  PRAGMA integrity_check;
+} {10015 ok}
+do_execsql_test index7-2.102eqp {
+  EXPLAIN QUERY PLAN
+  SELECT b FROM t2 WHERE a=15;
+} {~/.*INDEX t2a2.*/}
+do_execsql_test index7-2.103 {
+  SELECT b FROM t2 WHERE a=15 AND a<100;
+} {10015}
+do_execsql_test index7-2.103eqp {
+  EXPLAIN QUERY PLAN
+  SELECT b FROM t2 WHERE a=15 AND a<100;
+} {/.*INDEX t2a2.*/}
+do_execsql_test index7-2.104 {
+  SELECT b FROM t2 WHERE a=515 AND a>200;
+} {10515}
+do_execsql_test index7-2.104eqp {
+  EXPLAIN QUERY PLAN
+  SELECT b FROM t2 WHERE a=515 AND a>200;
+} {/.*INDEX t2a2.*/}
+
+# Partial UNIQUE indices
+#
+do_execsql_test index7-3.1 {
+  CREATE TABLE t3(a,b PRIMARY KEY) without rowid;
+  INSERT INTO t3 SELECT value, value FROM nums WHERE value<200;
+  UPDATE t3 SET a=999 WHERE b%5!=0;
+  CREATE UNIQUE INDEX t3a ON t3(a) WHERE a<>999;
+} {}
+do_test index7-3.2 {
+  # unable to insert a duplicate row a-value that is not 999.
+  catchsql {
+    INSERT INTO t3(a,b) VALUES(150, 'test1');
+  }
+} {1 {column a is not unique}}
+do_test index7-3.3 {
+  # can insert multiple rows with a==999 because such rows are not
+  # part of the unique index.
+  catchsql {
+    INSERT INTO t3(a,b) VALUES(999, 'test1'), (999, 'test2');
+  }
+} {0 {}}
+do_execsql_test index7-3.4 {
+  SELECT count(*) FROM t3 WHERE a=999;
+} {162}
+integrity_check index7-3.5
+
+do_execsql_test index7-4.0 {
+  VACUUM;
+  PRAGMA integrity_check;
+} {ok}
+
+# Silently ignore database name qualifiers in partial indices.
+#
+do_execsql_test index7-5.0 {
+  CREATE INDEX t3b ON t3(b) WHERE xyzzy.t3.b BETWEEN 5 AND 10;
+                               /* ^^^^^-- ignored */
+  ANALYZE;
+  SELECT count(*) FROM t3 WHERE t3.b BETWEEN 5 AND 10;
+  SELECT stat+0 FROM sqlite_stat1 WHERE idx='t3b';
+} {6 6}
+
+finish_test