diff --git a/manifest b/manifest
index d62ec50283..6553897649 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Still\smore\srefinements\sto\sthe\shasHotJournal()\sfix\sof\sticket\s#3883.\s(CVS\s6689)
-D 2009-05-29T11:57:38
+C Refinements\sin\sexpression\shandling\slogic\sthat\shave\sresulted\sfrom\srecent\nstructural\stesting.\s(CVS\s6690)
+D 2009-05-29T14:39:08
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in 583e87706abc3026960ed759aff6371faf84c211
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -114,7 +114,7 @@ F src/callback.c 57359fa93de47c341b6b8ee504a88ff276397686
 F src/complete.c 5ad5c6cd4548211867c204c41a126d73a9fbcea0
 F src/date.c ab5f7137656652a48434d64f96bdcdc823bb23b3
 F src/delete.c cb791855c7948cecc96def9d97989879ca26f257
-F src/expr.c 9d25d7229719334dc87909f8094b10d033b994f1
+F src/expr.c ba5ba6a6332ec07d81cda97585dabf6c88bffbab
 F src/fault.c dc88c821842157460750d2d61a8a8b4197d047ff
 F src/func.c 9d7b47729c337c5e4b78d795922ed34eec4aef67
 F src/global.c 448419c44ce0701104c2121b0e06919b44514c0c
@@ -156,7 +156,7 @@ F src/pragma.c d4a6fd74fd1dba0f22c8930791f7fbbe80d2ef26
 F src/prepare.c f46d1a029760edee5447e27164fb3ae10e2a6839
 F src/printf.c 3f4dca207a88258d37af5a7a03e800a825fe6456
 F src/random.c 676b9d7ac820fe81e6fb2394ac8c10cff7f38628
-F src/resolve.c fc6fdd01305518fd1462e1621213e63bd011a115
+F src/resolve.c 42065c05d4dd56894d1ae232974668674435e468
 F src/rowset.c c64dafba1f9fd876836c8db8682966b9d197eb1f
 F src/select.c fd1737a667bab296f50049a841b3aba5ec89418e
 F src/shell.c 7eacd0bdaa887931f5ff205c9defc3e8df95a2dd
@@ -226,7 +226,7 @@ F test/async.test c042ff6d2a29f65e05d498a52448229d25bb5d9d
 F test/async2.test bf5e2ca2c96763b4cba3d016249ad7259a5603b6
 F test/async3.test 93edaa9122f498e56ea98c36c72abc407f4fb11e
 F test/async4.test bdb997924394a2034ff3df1d839ff95b2e602ed4
-F test/attach.test e710d543769305942e9354cee5aba8cfcbe89577
+F test/attach.test 1d1be27b9e4c654f9bb14d011a4a87753c0b197a
 F test/attach2.test a295d2d7061adcee5884ef4a93c7c96a82765437
 F test/attach3.test 7b92dc8e40c1ebca9732ca6f2d3fefbd46f196df
 F test/attachmalloc.test cf8cf17d183de357b1147a9baacbdfc85b940b61
@@ -731,7 +731,7 @@ F tool/speedtest16.c c8a9c793df96db7e4933f0852abb7a03d48f2e81
 F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
-P a2ba61d927a06c390a9a818a013328092b802222
-R df5faf03661654bce8e5953dac271838
+P 726b425e43e5d864e7e83853bdf134debc1ffb59
+R 7782c740d0e684d85e0d73fa4ed3175a
 U drh
-Z c67a8bef852bbf3b9d8397d68afe4414
+Z 3b276276ba95400e6569bffb7e01828d
diff --git a/manifest.uuid b/manifest.uuid
index 87047ac88a..56bb8a9768 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-726b425e43e5d864e7e83853bdf134debc1ffb59
\ No newline at end of file
+bd89f2c29b00e6b473f30c2e929d2f626721ad92
\ No newline at end of file
diff --git a/src/expr.c b/src/expr.c
index e69cc2d696..d0b96a039a 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -12,7 +12,7 @@
 ** This file contains routines used for analyzing expressions and
 ** for generating VDBE code that evaluates expressions in SQLite.
 **
-** $Id: expr.c,v 1.439 2009/05/28 21:04:38 drh Exp $
+** $Id: expr.c,v 1.440 2009/05/29 14:39:08 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -1378,7 +1378,7 @@ int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
   ** ephemeral table.
   */
   p = (ExprHasProperty(pX, EP_xIsSelect) ? pX->x.pSelect : 0);
-  if( pParse->nErr==0 && isCandidateForInOpt(p) ){
+  if( ALWAYS(pParse->nErr==0) && isCandidateForInOpt(p) ){
     sqlite3 *db = pParse->db;              /* Database connection */
     Expr *pExpr = p->pEList->a[0].pExpr;   /* Expression <column> */
     int iCol = pExpr->iColumn;             /* Index of column <column> */
@@ -1489,17 +1489,29 @@ int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
 ** to some integer key column of a table B-Tree. In this case, use an
 ** intkey B-Tree to store the set of IN(...) values instead of the usual
 ** (slower) variable length keys B-Tree.
+**
+** If rMayHaveNull is non-zero, that means that the operation is an IN
+** (not a SELECT or EXISTS) and that the RHS might contains NULLs.
+** Furthermore, the IN is in a WHERE clause and that we really want
+** to iterate over the RHS of the IN operator in order to quickly locate
+** all corresponding LHS elements.  All this routine does is initialize
+** the register given by rMayHaveNull to NULL.  Calling routines will take
+** care of changing this register value to non-NULL if the RHS is NULL-free.
+**
+** If rMayHaveNull is zero, that means that the subquery is being used
+** for membership testing only.  There is no need to initialize any
+** registers to indicate the presense or absence of NULLs on the RHS.
 */
 #ifndef SQLITE_OMIT_SUBQUERY
 void sqlite3CodeSubselect(
-  Parse *pParse, 
-  Expr *pExpr, 
-  int rMayHaveNull,
-  int isRowid
+  Parse *pParse,          /* Parsing context */
+  Expr *pExpr,            /* The IN, SELECT, or EXISTS operator */
+  int rMayHaveNull,       /* Register that records whether NULLs exist in RHS */
+  int isRowid             /* If true, LHS of IN operator is a rowid */
 ){
   int testAddr = 0;                       /* One-time test address */
   Vdbe *v = sqlite3GetVdbe(pParse);
-  if( v==0 ) return;
+  if( NEVER(v==0) ) return;
   sqlite3ExprCachePush(pParse);
 
   /* This code must be run in its entirety every time it is encountered
@@ -1567,11 +1579,11 @@ void sqlite3CodeSubselect(
           return;
         }
         pEList = pExpr->x.pSelect->pEList;
-        if( pEList && pEList->nExpr>0 ){ 
+        if( ALWAYS(pEList!=0 && pEList->nExpr>0) ){ 
           keyInfo.aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
               pEList->a[0].pExpr);
         }
-      }else if( pExpr->x.pList ){
+      }else if( pExpr->x.pList!=0 ){
         /* Case 2:     expr IN (exprlist)
         **
         ** For each expression, build an index key from the evaluation and
@@ -1627,14 +1639,20 @@ void sqlite3CodeSubselect(
     }
 
     case TK_EXISTS:
-    case TK_SELECT: {
-      /* This has to be a scalar SELECT.  Generate code to put the
+    case TK_SELECT:
+    default: {
+      testcase( pExpr->op==TK_EXISTS );
+      testcase( pExpr->op==TK_SELECT );
+      assert( pExpr->op==TK_EXISTS || pExpr->op==TK_SELECT );
+      /* If this has to be a scalar SELECT.  Generate code to put the
       ** value of this select in a memory cell and record the number
-      ** of the memory cell in iColumn.
+      ** of the memory cell in iColumn.  If this is an EXISTS, write
+      ** an integer 0 (not exists) or 1 (exists) into a memory cell
+      ** and record that memory cell in iColumn.
       */
-      static const Token one = { "1", 1 };
-      Select *pSel;
-      SelectDest dest;
+      static const Token one = { "1", 1 };  /* Token for literal value 1 */
+      Select *pSel;                         /* SELECT statement to encode */
+      SelectDest dest;                      /* How to deal with SELECt result */
 
       assert( ExprHasProperty(pExpr, EP_xIsSelect) );
       pSel = pExpr->x.pSelect;
@@ -1688,8 +1706,7 @@ static char *dup8bytes(Vdbe *v, const char *in){
 ** like the continuation of the number.
 */
 static void codeReal(Vdbe *v, const char *z, int negateFlag, int iMem){
-  assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );
-  if( z ){
+  if( ALWAYS(z!=0) ){
     double value;
     char *zV;
     sqlite3AtoF(z, &value);
@@ -1713,19 +1730,14 @@ static void codeReal(Vdbe *v, const char *z, int negateFlag, int iMem){
 ** like the continuation of the number.
 */
 static void codeInteger(Vdbe *v, Expr *pExpr, int negFlag, int iMem){
-  const char *z;
   if( pExpr->flags & EP_IntValue ){
     int i = pExpr->u.iValue;
     if( negFlag ) i = -i;
     sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
-  }else if( (z = pExpr->u.zToken)!=0 ){
-    int i;
-    int n = sqlite3Strlen30(pExpr->u.zToken);
-    assert( !sqlite3Isdigit(z[n]) );
-    if( sqlite3GetInt32(z, &i) ){
-      if( negFlag ) i = -i;
-      sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
-    }else if( sqlite3FitsIn64Bits(z, negFlag) ){
+  }else{
+    const char *z = pExpr->u.zToken;
+    assert( z!=0 );
+    if( sqlite3FitsIn64Bits(z, negFlag) ){
       i64 value;
       char *zV;
       sqlite3Atoi64(z, &value);
diff --git a/src/resolve.c b/src/resolve.c
index dc750b1e99..55a47ca444 100644
--- a/src/resolve.c
+++ b/src/resolve.c
@@ -14,7 +14,7 @@
 ** resolve all identifiers by associating them with a particular
 ** table and column.
 **
-** $Id: resolve.c,v 1.26 2009/05/28 14:34:50 drh Exp $
+** $Id: resolve.c,v 1.27 2009/05/29 14:39:08 drh Exp $
 */
 #include "sqliteInt.h"
 #include <stdlib.h>
@@ -1127,7 +1127,7 @@ int sqlite3ResolveExprNames(
 #if SQLITE_MAX_EXPR_DEPTH>0
   pNC->pParse->nHeight -= pExpr->nHeight;
 #endif
-  if( pNC->nErr>0 ){
+  if( pNC->nErr>0 || w.pParse->nErr>0 ){
     ExprSetProperty(pExpr, EP_Error);
   }
   if( pNC->hasAgg ){
diff --git a/test/attach.test b/test/attach.test
index 8dda7f2a82..7ee659749c 100644
--- a/test/attach.test
+++ b/test/attach.test
@@ -12,7 +12,7 @@
 # focus of this script is testing the ATTACH and DETACH commands
 # and related functionality.
 #
-# $Id: attach.test,v 1.51 2009/05/28 01:00:56 drh Exp $
+# $Id: attach.test,v 1.52 2009/05/29 14:39:08 drh Exp $
 #
 
 set testdir [file dirname $argv0]
@@ -756,7 +756,7 @@ ifcapable subquery {
       DETACH RAISE ( IGNORE ) IN ( SELECT "AAAAAA" . * ORDER BY 
       REGISTER LIMIT "AAAAAA" . "AAAAAA" OFFSET RAISE ( IGNORE ) NOT NULL )
     }
-  } {1 {invalid name: ""}}
+  } {1 {no such table: AAAAAA}}
 }
 
 # Create a malformed file (a file that is not a valid database)