diff --git a/manifest b/manifest
index a17919ee09..1ea2e4a1dc 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Import\sthe\sautomatic\scomment\sgenerating\schanges\sfrom\strunk.
-D 2013-10-29T20:47:26.079
+C Merge\sEXPLAIN\senhancements\sfrom\strunk.
+D 2013-10-30T02:37:50.150
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 0522b53cdc1fcfc18f3a98e0246add129136c654
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -145,7 +145,7 @@ F main.mk c6a433cb334bbb019625c137ab5d5e7568b47cff
 F mkdll.sh 7d09b23c05d56532e9d44a50868eb4b12ff4f74a
 F mkextu.sh 416f9b7089d80e5590a29692c9d9280a10dbad9f
 F mkextw.sh d2a981497b404d6498f5ff3e3b1f3816bdfcb338
-F mkopcodec.awk 393b20a2a99557ca695f7e1261c32d087ff7c0b4
+F mkopcodec.awk c2ff431854d702cdd2d779c9c0d1f58fa16fa4ea
 F mkopcodeh.awk 987ee588ff3bb4043bed2185c1ee2bdc39b1e526
 F mkso.sh fd21c06b063bb16a5d25deea1752c2da6ac3ed83
 F mptest/config01.test 3c6adcbc50b991866855f1977ff172eb6d901271
@@ -223,7 +223,7 @@ F src/shell.c d5eebdc6034014103de2b9d58e1d3f6f7de0fb50
 F src/sqlite.h.in 547a44dd4ff4d975e92a645ea2d609e543a83d0f
 F src/sqlite3.rc 11094cc6a157a028b301a9f06b3d03089ea37c3e
 F src/sqlite3ext.h 886f5a34de171002ad46fae8c36a7d8051c190fc
-F src/sqliteInt.h 2653257af49bf87af81d7c35899297043f10879a
+F src/sqliteInt.h 03e6459326d16123441ada0a053163fd1e2e341d
 F src/sqliteLimit.h 164b0e6749d31e0daa1a4589a169d31c0dec7b3d
 F src/status.c 7ac05a5c7017d0b9f0b4bcd701228b784f987158
 F src/table.c 2cd62736f845d82200acfa1287e33feb3c15d62e
@@ -274,16 +274,16 @@ F src/test_vfs.c e72f555ef7a59080f898fcf1a233deb9eb704ea9
 F src/test_vfstrace.c 34b544e80ba7fb77be15395a609c669df2e660a2
 F src/test_wsd.c 41cadfd9d97fe8e3e4e44f61a4a8ccd6f7ca8fe9
 F src/tokenize.c 70061085a51f2f4fc15ece94f32c03bcb78e63b2
-F src/trigger.c ba0a883cd536b7dfdd4df3733001f5372a4299da
+F src/trigger.c 53d6b5d50b3b23d4fcd0a36504feb5cff9aed716
 F src/update.c e39378bc5ed0c42e80624229703e59b5c7a4d50a
 F src/utf.c 6fc6c88d50448c469c5c196acf21617a24f90269
 F src/util.c 2fa6c821d28bbdbeec1b2a7b091a281c9ef8f918
 F src/vacuum.c 3728d74919d4fb1356f9e9a13e27773db60b7179
-F src/vdbe.c cb3df2d7b2ebadf22a39efcfb12a1277e273616e
-F src/vdbe.h 4f554b5627f26710c4c36d919110a3fc611ca5c4
+F src/vdbe.c 3c98b77343f8a1f4624b86795bf29cfd008b0e4a
+F src/vdbe.h 6bdee35c54d57fd52733d4c542781820009311dc
 F src/vdbeInt.h 42dcff74dbeb2b071e569b53f885fc9c2e4b4cb0
 F src/vdbeapi.c 93a22a9ba2abe292d5c2cf304d7eb2e894dde0ed
-F src/vdbeaux.c 3c36d92d3ad7225e0436474f4256243e5ceaeabb
+F src/vdbeaux.c 4b01ac1c84534cd5a240dffba6e8173aeff628c5
 F src/vdbeblob.c ef973d8d9f8170015343dd8824f795da675caa87
 F src/vdbemem.c 6087553f2c61c06c8e1ab3959a60e174d6240c98
 F src/vdbesort.c 3937e06b2a0e354500e17dc206ef4c35770a5017
@@ -1127,7 +1127,7 @@ F tool/vdbe-compress.tcl f12c884766bd14277f4fcedcae07078011717381
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh d1a6de74685f360ab718efda6265994b99bbea01
 F tool/win/sqlite.vsix 030f3eeaf2cb811a3692ab9c14d021a75ce41fff
-P 141a38a7a636e3e4255b59c27df4a1b3d6f26e97 5f310c6a22b8bb5f860296074aee130c14101681
-R 092c8ad63995bcb3387c2f88e6abbbb4
+P 8bb51da1305d5e35c7b75bbb176c21e04ea2a48a e1a89b56f7173166bb9224e2e360fd67ad3399c3
+R 880887149918aa46e6b88c9f75c81815
 U drh
-Z 2daff0292132d8122decef0d377e8179
+Z 77a0862498d22b2e5464d4447bba8799
diff --git a/manifest.uuid b/manifest.uuid
index bc00d07846..5eb709e725 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-8bb51da1305d5e35c7b75bbb176c21e04ea2a48a
\ No newline at end of file
+2fcac056074f0a23884ab5425003a7ca1d35c2a8
\ No newline at end of file
diff --git a/mkopcodec.awk b/mkopcodec.awk
index f4a09bf3e5..de19068c20 100644
--- a/mkopcodec.awk
+++ b/mkopcodec.awk
@@ -14,7 +14,7 @@ BEGIN {
   printf "#if !defined(SQLITE_OMIT_EXPLAIN)"
   printf    " || defined(VDBE_PROFILE)"
   print     " || defined(SQLITE_DEBUG)"
-  print "#if defined(SQLITE_DEBUG)"
+  print "#if defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) || defined(SQLITE_DEBUG)"
   print "# define OpHelp(X) \"\\0\" X"
   print "#else"
   print "# define OpHelp(X)"
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 0d5a68d504..ec4aaa14db 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -217,6 +217,13 @@
 # undef NDEBUG
 #endif
 
+/*
+** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
+*/
+#if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
+# define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
+#endif
+
 /*
 ** The testcase() macro is used to aid in coverage testing.  When 
 ** doing coverage testing, the condition inside the argument to
diff --git a/src/trigger.c b/src/trigger.c
index 774711f0f5..607b831243 100644
--- a/src/trigger.c
+++ b/src/trigger.c
@@ -784,7 +784,7 @@ static int codeTriggerProgram(
   return 0;
 }
 
-#ifdef SQLITE_DEBUG
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
 /*
 ** This function is used to add VdbeComment() annotations to a VDBE
 ** program. It is not used in production code, only for debugging.
diff --git a/src/vdbe.c b/src/vdbe.c
index f0400a64dc..1dd8757f4b 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -1035,7 +1035,7 @@ case OP_Variable: {            /* out2-prerelease */
 }
 
 /* Opcode: Move P1 P2 P3 * *
-** Synopsis:  r[P2]=r[P1] N=P3
+** Synopsis:  r[P2@P3]=r[P1@P3]
 **
 ** Move the values in register P1..P1+P3 over into
 ** registers P2..P2+P3.  Registers P1..P1+P3 are
@@ -1078,7 +1078,7 @@ case OP_Move: {
 }
 
 /* Opcode: Copy P1 P2 P3 * *
-** Synopsis: r[P2]=r[P1] N=P3
+** Synopsis: r[P2@P3]=r[P1@P3]
 **
 ** Make a copy of registers P1..P1+P3 into registers P2..P2+P3.
 **
@@ -1132,7 +1132,7 @@ case OP_SCopy: {            /* in1, out2 */
 }
 
 /* Opcode: ResultRow P1 P2 * * *
-** Synopsis:  output=r[P1].. columns=P1
+** Synopsis:  output=r[P1@P2]
 **
 ** The registers P1 through P1+P2-1 contain a single row of
 ** results. This opcode causes the sqlite3_step() call to terminate
@@ -1400,7 +1400,7 @@ case OP_CollSeq: {
 }
 
 /* Opcode: Function P1 P2 P3 P4 P5
-** Synopsis: r[P3]=func(r[P2]..) N=P5
+** Synopsis: r[P3]=func(r[P2@P5])
 **
 ** Invoke a user function (P4 is a pointer to a Function structure that
 ** defines the function) with P5 arguments taken from register P2 and
@@ -2513,7 +2513,7 @@ op_column_out:
 }
 
 /* Opcode: Affinity P1 P2 * P4 *
-** Synopsis: affinity(r[P1]) N=P2
+** Synopsis: affinity(r[P1@P2])
 **
 ** Apply affinities to a range of P2 registers starting with P1.
 **
@@ -2540,7 +2540,7 @@ case OP_Affinity: {
 }
 
 /* Opcode: MakeRecord P1 P2 P3 P4 *
-** Synopsis: r[P3]=rec(r[P1]..) N=P2
+** Synopsis: r[P3]=mkrec(r[P1@P2])
 **
 ** Convert P2 registers beginning with P1 into the [record format]
 ** use as a data record in a database table or as a key
@@ -3379,7 +3379,7 @@ case OP_SorterOpen: {
 }
 
 /* Opcode: OpenPseudo P1 P2 P3 * P5
-** Synopsis: content in r[P2].. N=P3
+** Synopsis: content in r[P2@P3]
 **
 ** Open a new cursor that points to a fake table that contains a single
 ** row of data.  The content of that one row in the content of memory
@@ -3422,7 +3422,7 @@ case OP_Close: {
 }
 
 /* Opcode: SeekGe P1 P2 P3 P4 *
-** Synopsis: key=r[P3].. N=P4
+** Synopsis: key=r[P3@P4]
 **
 ** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
 ** use the value in register P3 as the key.  If cursor P1 refers 
@@ -3436,7 +3436,7 @@ case OP_Close: {
 ** See also: Found, NotFound, Distinct, SeekLt, SeekGt, SeekLe
 */
 /* Opcode: SeekGt P1 P2 P3 P4 *
-** Synopsis: key=r[P3].. N=P4
+** Synopsis: key=r[P3@P4]
 **
 ** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
 ** use the value in register P3 as a key. If cursor P1 refers 
@@ -3450,7 +3450,7 @@ case OP_Close: {
 ** See also: Found, NotFound, Distinct, SeekLt, SeekGe, SeekLe
 */
 /* Opcode: SeekLt P1 P2 P3 P4 * 
-** Synopsis: key=r[P3].. N=P4
+** Synopsis: key=r[P3@P4]
 **
 ** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
 ** use the value in register P3 as a key. If cursor P1 refers 
@@ -3464,7 +3464,7 @@ case OP_Close: {
 ** See also: Found, NotFound, Distinct, SeekGt, SeekGe, SeekLe
 */
 /* Opcode: SeekLe P1 P2 P3 P4 *
-** Synopsis: key=r[P3].. N=P4
+** Synopsis: key=r[P3@P4]
 **
 ** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
 ** use the value in register P3 as a key. If cursor P1 refers 
@@ -3658,7 +3658,7 @@ case OP_Seek: {    /* in2 */
   
 
 /* Opcode: Found P1 P2 P3 P4 *
-** Synopsis: key=r[P3].. N=P4
+** Synopsis: key=r[P3@P4]
 **
 ** If P4==0 then register P3 holds a blob constructed by MakeRecord.  If
 ** P4>0 then register P3 is the first of P4 registers that form an unpacked
@@ -3671,7 +3671,7 @@ case OP_Seek: {    /* in2 */
 ** See also: NotFound, NoConflict, NotExists. SeekGe
 */
 /* Opcode: NotFound P1 P2 P3 P4 *
-** Synopsis: key=r[P3] N=P4
+** Synopsis: key=r[P3@P4]
 **
 ** If P4==0 then register P3 holds a blob constructed by MakeRecord.  If
 ** P4>0 then register P3 is the first of P4 registers that form an unpacked
@@ -3686,6 +3686,7 @@ case OP_Seek: {    /* in2 */
 ** See also: Found, NotExists, NoConflict
 */
 /* Opcode: NoConflict P1 P2 P3 P4 *
+** Synopsis: key=r[P3@P4]
 **
 ** If P4==0 then register P3 holds a blob constructed by MakeRecord.  If
 ** P4>0 then register P3 is the first of P4 registers that form an unpacked
@@ -4585,7 +4586,7 @@ case OP_IdxInsert: {        /* in2 */
 }
 
 /* Opcode: IdxDelete P1 P2 P3 * *
-** Synopsis: key=r[P2]..
+** Synopsis: key=r[P2@P3]
 **
 ** The content of P3 registers starting at register P2 form
 ** an unpacked index key. This opcode removes that entry from the 
@@ -4658,7 +4659,7 @@ case OP_IdxRowid: {              /* out2-prerelease */
 }
 
 /* Opcode: IdxGE P1 P2 P3 P4 P5
-** Synopsis: key=r[P3] N=P4
+** Synopsis: key=r[P3@P4]
 **
 ** The P4 register values beginning with P3 form an unpacked index 
 ** key that omits the ROWID.  Compare this key value against the index 
@@ -4673,7 +4674,7 @@ case OP_IdxRowid: {              /* out2-prerelease */
 ** the result is false whereas it would be true with IdxGT.
 */
 /* Opcode: IdxLT P1 P2 P3 P4 P5
-** Synopsis: key=r[P3] N=P4
+** Synopsis: key=r[P3@P4]
 **
 ** The P4 register values beginning with P3 form an unpacked index 
 ** key that omits the ROWID.  Compare this key value against the index 
@@ -5416,7 +5417,7 @@ case OP_IfZero: {        /* jump, in1 */
 }
 
 /* Opcode: AggStep * P2 P3 P4 P5
-** Synopsis: accum=r[P3] step(r[P2]..) N=P5
+** Synopsis: accum=r[P3] step(r[P2@P5])
 **
 ** Execute the step function for an aggregate.  The
 ** function has P5 arguments.   P4 is a pointer to the FuncDef
@@ -6034,7 +6035,7 @@ case OP_VRename: {
 
 #ifndef SQLITE_OMIT_VIRTUALTABLE
 /* Opcode: VUpdate P1 P2 P3 P4 *
-** Synopsis: data=r[P3] N=P2
+** Synopsis: data=r[P3@P2]
 **
 ** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
 ** This opcode invokes the corresponding xUpdate method. P2 values
diff --git a/src/vdbe.h b/src/vdbe.h
index a6cc915444..966ea75264 100644
--- a/src/vdbe.h
+++ b/src/vdbe.h
@@ -61,7 +61,7 @@ struct VdbeOp {
     SubProgram *pProgram;  /* Used when p4type is P4_SUBPROGRAM */
     int (*xAdvance)(BtCursor *, int *);
   } p4;
-#ifdef SQLITE_DEBUG
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
   char *zComment;          /* Comment to improve readability */
 #endif
 #ifdef VDBE_PROFILE
@@ -219,7 +219,7 @@ void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
 #endif
 
 
-#ifndef NDEBUG
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
   void sqlite3VdbeComment(Vdbe*, const char*, ...);
 # define VdbeComment(X)  sqlite3VdbeComment X
   void sqlite3VdbeNoopComment(Vdbe*, const char*, ...);
diff --git a/src/vdbeaux.c b/src/vdbeaux.c
index c71b29caff..97c1c8cfc7 100644
--- a/src/vdbeaux.c
+++ b/src/vdbeaux.c
@@ -144,8 +144,10 @@ int sqlite3VdbeAddOp3(Vdbe *p, int op, int p1, int p2, int p3){
   pOp->p3 = p3;
   pOp->p4.p = 0;
   pOp->p4type = P4_NOTUSED;
-#ifdef SQLITE_DEBUG
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
   pOp->zComment = 0;
+#endif
+#ifdef SQLITE_DEBUG
   if( p->db->flags & SQLITE_VdbeAddopTrace ){
     sqlite3VdbePrintOp(0, i, &p->aOp[i]);
   }
@@ -532,8 +534,10 @@ int sqlite3VdbeAddOpList(Vdbe *p, int nOp, VdbeOpList const *aOp){
       pOut->p4type = P4_NOTUSED;
       pOut->p4.p = 0;
       pOut->p5 = 0;
-#ifdef SQLITE_DEBUG
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
       pOut->zComment = 0;
+#endif
+#ifdef SQLITE_DEBUG
       if( p->db->flags & SQLITE_VdbeAddopTrace ){
         sqlite3VdbePrintOp(0, i+addr, &p->aOp[i+addr]);
       }
@@ -663,7 +667,7 @@ static void vdbeFreeOpArray(sqlite3 *db, Op *aOp, int nOp){
     Op *pOp;
     for(pOp=aOp; pOp<&aOp[nOp]; pOp++){
       freeP4(db, pOp->p4type, pOp->p4.p);
-#ifdef SQLITE_DEBUG
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
       sqlite3DbFree(db, pOp->zComment);
 #endif     
     }
@@ -781,7 +785,7 @@ void sqlite3VdbeChangeP4(Vdbe *p, int addr, const char *zP4, int n){
   }
 }
 
-#ifndef NDEBUG
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
 /*
 ** Change the comment on the most recently coded instruction.  Or
 ** insert a No-op and add the comment to that new instruction.  This
@@ -856,11 +860,28 @@ VdbeOp *sqlite3VdbeGetOp(Vdbe *p, int addr){
   }
 }
 
-#if defined(SQLITE_DEBUG)
+#if defined(SQLITE_ENABLE_EXPLAIN_COMMENTS)
+/*
+** Return an integer value for one of the parameters to the opcode pOp
+** determined by character c.
+*/
+static int translateP(char c, const Op *pOp){
+  if( c=='1' ) return pOp->p1;
+  if( c=='2' ) return pOp->p2;
+  if( c=='3' ) return pOp->p3;
+  if( c=='4' ) return pOp->p4.i;
+  return pOp->p5;
+}
+
 /*
 ** Compute a string for the "comment" field of a VDBE opcode listing
 */
-static int displayComment(Op *pOp, const char *zP4, char *zTemp, int nTemp){
+static int displayComment(
+  const Op *pOp,     /* The opcode to be commented */
+  const char *zP4,   /* Previously obtained value for P4 */
+  char *zTemp,       /* Write result here */
+  int nTemp          /* Space available in zTemp[] */
+){
   const char *zOpName;
   const char *zSynopsis;
   int nOpName;
@@ -869,28 +890,32 @@ static int displayComment(Op *pOp, const char *zP4, char *zTemp, int nTemp){
   nOpName = sqlite3Strlen30(zOpName);
   if( zOpName[nOpName+1] ){
     int seenCom = 0;
+    char c;
     zSynopsis = zOpName += nOpName + 1;
-    for(ii=jj=0; jj<nTemp-1 && zSynopsis[ii]; ii++){
-      if( zSynopsis[ii]=='P' ){
-        int v;
-        const char *zShow = 0;
-        ii++;
-        switch( zSynopsis[ii] ){
-          case '1': v = pOp->p1;  break;
-          case '2': v = pOp->p2;  break;
-          case '3': v = pOp->p3;  break;
-          case '5': v = pOp->p5;  break;
-          case '4': zShow = zP4;  break;
-          case 'X': zShow = pOp->zComment; seenCom = 1; break;
-        }
-        if( zShow ){
-          sqlite3_snprintf(nTemp-jj, zTemp+jj, "%s", zShow);
+    for(ii=jj=0; jj<nTemp-1 && (c = zSynopsis[ii])!=0; ii++){
+      if( c=='P' ){
+        c = zSynopsis[++ii];
+        if( c=='4' ){
+          sqlite3_snprintf(nTemp-jj, zTemp+jj, "%s", zP4);
+        }else if( c=='X' ){
+          sqlite3_snprintf(nTemp-jj, zTemp+jj, "%s", pOp->zComment);
+          seenCom = 1;
         }else{
-          sqlite3_snprintf(nTemp-jj, zTemp+jj, "%d", v);
+          int v1 = translateP(c, pOp);
+          int v2;
+          sqlite3_snprintf(nTemp-jj, zTemp+jj, "%d", v1);
+          if( strncmp(zSynopsis+ii+1, "@P", 2)==0 ){
+            ii += 3;
+            jj += sqlite3Strlen30(zTemp+jj);
+            v2 = translateP(zSynopsis[ii], pOp);
+            if( v2>1 ) sqlite3_snprintf(nTemp-jj, zTemp+jj, "..%d", v1+v2-1);
+          }else if( strncmp(zSynopsis+ii+1, "..P3", 4)==0 && pOp->p3==0 ){
+            ii += 4;
+          }
         }
         jj += sqlite3Strlen30(zTemp+jj);
       }else{
-        zTemp[jj++] = zSynopsis[ii];
+        zTemp[jj++] = c;
       }
     }
     if( !seenCom && jj<nTemp-5 && pOp->zComment ){
@@ -1107,7 +1132,7 @@ void sqlite3VdbePrintOp(FILE *pOut, int pc, Op *pOp){
   static const char *zFormat1 = "%4d %-13s %4d %4d %4d %-4s %.2X %s\n";
   if( pOut==0 ) pOut = stdout;
   zP4 = displayP4(pOp, zPtr, sizeof(zPtr));
-#ifdef SQLITE_DEBUG
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
   displayComment(pOp, zP4, zCom, sizeof(zCom));
 #else
   zCom[0] = 0
@@ -1353,7 +1378,7 @@ int sqlite3VdbeList(
       pMem->enc = SQLITE_UTF8;
       pMem++;
   
-#ifdef SQLITE_DEBUG
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
       if( sqlite3VdbeMemGrow(pMem, 500, 0) ){
         assert( p->db->mallocFailed );
         return SQLITE_ERROR;