Merge trunk changes into the sessions branch.

FossilOrigin-Name: 9f18e78f039ffa89a8806810ad385bdc51bc88ed

13 files changed, 374 insertions, 164 deletions

diff --git a/src/analyze.c b/src/analyze.c
index 2952b364c..4dcd7e8b8 100644
--- a/src/analyze.c
+++ b/src/analyze.c
@@ -1002,7 +1002,7 @@ static void analyzeOneTable(
     if( aGotoChng==0 ) continue;
 
     /* Populate the register containing the index name. */
-    if( pIdx->autoIndex==2 && !HasRowid(pTab) ){
+    if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) ){
       zIdxName = pTab->zName;
     }else{
       zIdxName = pIdx->zName;
diff --git a/src/btree.c b/src/btree.c
index e843a946b..9032a9304 100644
--- a/src/btree.c
+++ b/src/btree.c
@@ -4218,12 +4218,6 @@ static const void *fetchPayload(
   assert( cursorHoldsMutex(pCur) );
   assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
   assert( pCur->info.nSize>0 );
-#if 0
-  if( pCur->info.nSize==0 ){
-    btreeParseCell(pCur->apPage[pCur->iPage], pCur->aiIdx[pCur->iPage],
-                   &pCur->info);
-  }
-#endif
   *pAmt = pCur->info.nLocal;
   return (void*)(pCur->info.pCell + pCur->info.nHeader);
 }
diff --git a/src/build.c b/src/build.c
index 8615fe76d..677ba326c 100644
--- a/src/build.c
+++ b/src/build.c
@@ -757,7 +757,7 @@ int sqlite3CheckObjectName(Parse *pParse, const char *zName){
 */
 Index *sqlite3PrimaryKeyIndex(Table *pTab){
   Index *p;
-  for(p=pTab->pIndex; p && p->autoIndex!=2; p=p->pNext){}
+  for(p=pTab->pIndex; p && !IsPrimaryKeyIndex(p); p=p->pNext){}
   return p;
 }
 
@@ -1286,7 +1286,7 @@ void sqlite3AddPrimaryKey(
     p = sqlite3CreateIndex(pParse, 0, 0, 0, pList, onError, 0,
                            0, sortOrder, 0);
     if( p ){
-      p->autoIndex = 2;
+      p->idxType = SQLITE_IDXTYPE_PRIMARYKEY;
       if( v ) sqlite3VdbeJumpHere(v, pParse->addrSkipPK);
     }
     pList = 0;
@@ -1661,7 +1661,7 @@ static void convertToWithoutRowidTable(Parse *pParse, Table *pTab){
     assert( pParse->pNewTable==pTab );
     pPk = sqlite3CreateIndex(pParse, 0, 0, 0, pList, pTab->keyConf, 0, 0, 0, 0);
     if( pPk==0 ) return;
-    pPk->autoIndex = 2;
+    pPk->idxType = SQLITE_IDXTYPE_PRIMARYKEY;
     pTab->iPKey = -1;
   }else{
     pPk = sqlite3PrimaryKeyIndex(pTab);
@@ -1684,7 +1684,7 @@ static void convertToWithoutRowidTable(Parse *pParse, Table *pTab){
   */
   for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
     int n;
-    if( pIdx->autoIndex==2 ) continue;
+    if( IsPrimaryKeyIndex(pIdx) ) continue;
     for(i=n=0; i<nPk; i++){
       if( !hasColumn(pIdx->aiColumn, pIdx->nKeyCol, pPk->aiColumn[i]) ) n++;
     }
@@ -2764,7 +2764,7 @@ Index *sqlite3AllocateIndexObject(
 **
 ** If the index is created successfully, return a pointer to the new Index
 ** structure. This is used by sqlite3AddPrimaryKey() to mark the index
-** as the tables primary key (Index.autoIndex==2).
+** as the tables primary key (Index.idxType==SQLITE_IDXTYPE_PRIMARYKEY)
 */
 Index *sqlite3CreateIndex(
   Parse *pParse,     /* All information about this parse */
@@ -2979,7 +2979,7 @@ Index *sqlite3CreateIndex(
   pIndex->pTable = pTab;
   pIndex->onError = (u8)onError;
   pIndex->uniqNotNull = onError!=OE_None;
-  pIndex->autoIndex = (u8)(pName==0);
+  pIndex->idxType = pName ? SQLITE_IDXTYPE_APPDEF : SQLITE_IDXTYPE_UNIQUE;
   pIndex->pSchema = db->aDb[iDb].pSchema;
   pIndex->nKeyCol = pList->nExpr;
   if( pPIWhere ){
@@ -3091,7 +3091,7 @@ Index *sqlite3CreateIndex(
     for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
       int k;
       assert( pIdx->onError!=OE_None );
-      assert( pIdx->autoIndex );
+      assert( pIdx->idxType!=SQLITE_IDXTYPE_APPDEF );
       assert( pIndex->onError!=OE_None );
 
       if( pIdx->nKeyCol!=pIndex->nKeyCol ) continue;
@@ -3314,7 +3314,7 @@ void sqlite3DropIndex(Parse *pParse, SrcList *pName, int ifExists){
     pParse->checkSchema = 1;
     goto exit_drop_index;
   }
-  if( pIndex->autoIndex ){
+  if( pIndex->idxType!=SQLITE_IDXTYPE_APPDEF ){
     sqlite3ErrorMsg(pParse, "index associated with UNIQUE "
       "or PRIMARY KEY constraint cannot be dropped", 0);
     goto exit_drop_index;
@@ -3973,7 +3973,8 @@ void sqlite3UniqueConstraint(
   }
   zErr = sqlite3StrAccumFinish(&errMsg);
   sqlite3HaltConstraint(pParse, 
-    (pIdx->autoIndex==2)?SQLITE_CONSTRAINT_PRIMARYKEY:SQLITE_CONSTRAINT_UNIQUE,
+    IsPrimaryKeyIndex(pIdx) ? SQLITE_CONSTRAINT_PRIMARYKEY 
+                            : SQLITE_CONSTRAINT_UNIQUE,
     onError, zErr, P4_DYNAMIC, P5_ConstraintUnique);
 }
 
diff --git a/src/fkey.c b/src/fkey.c
index 336256e0f..c3cac276a 100644
--- a/src/fkey.c
+++ b/src/fkey.c
@@ -233,8 +233,8 @@ int sqlite3FkLocateIndex(
       if( zKey==0 ){
         /* If zKey is NULL, then this foreign key is implicitly mapped to 
         ** the PRIMARY KEY of table pParent. The PRIMARY KEY index may be 
-        ** identified by the test (Index.autoIndex==2).  */
-        if( pIdx->autoIndex==2 ){
+        ** identified by the test.  */
+        if( IsPrimaryKeyIndex(pIdx) ){
           if( aiCol ){
             int i;
             for(i=0; i<nCol; i++) aiCol[i] = pFKey->aCol[i].iFrom;
diff --git a/src/insert.c b/src/insert.c
index 31e16ba54..38e68ccdb 100644
--- a/src/insert.c
+++ b/src/insert.c
@@ -1475,7 +1475,7 @@ void sqlite3GenerateConstraintChecks(
           ** KEY values of this row before the update.  */
           int addrJump = sqlite3VdbeCurrentAddr(v)+pPk->nKeyCol;
           int op = OP_Ne;
-          int regCmp = (pIdx->autoIndex==2 ? regIdx : regR);
+          int regCmp = (IsPrimaryKeyIndex(pIdx) ? regIdx : regR);
   
           for(i=0; i<pPk->nKeyCol; i++){
             char *p4 = (char*)sqlite3LocateCollSeq(pParse, pPk->azColl[i]);
@@ -1576,7 +1576,7 @@ void sqlite3CompleteInsertion(
     sqlite3VdbeAddOp2(v, OP_IdxInsert, iIdxCur+i, aRegIdx[i]);
     pik_flags = 0;
     if( useSeekResult ) pik_flags = OPFLAG_USESEEKRESULT;
-    if( pIdx->autoIndex==2 && !HasRowid(pTab) ){
+    if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) ){
       assert( pParse->nested==0 );
       pik_flags |= OPFLAG_NCHANGE;
     }
@@ -1662,7 +1662,7 @@ int sqlite3OpenTableAndIndices(
   for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
     int iIdxCur = iBase++;
     assert( pIdx->pSchema==pTab->pSchema );
-    if( pIdx->autoIndex==2 && !HasRowid(pTab) && piDataCur ){
+    if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) && piDataCur ){
       *piDataCur = iIdxCur;
     }
     if( aToOpen==0 || aToOpen[i+1] ){
diff --git a/src/os_win.c b/src/os_win.c
index fcac665df..21f633e48 100644
--- a/src/os_win.c
+++ b/src/os_win.c
@@ -2825,7 +2825,7 @@ static int winGetReadLock(winFile *pFile){
     pFile->lastErrno = osGetLastError();
     /* No need to log a failure to lock */
   }
-  OSTRACE(("READ-LOCK file=%p, rc=%s\n", pFile->h, sqlite3ErrName(res)));
+  OSTRACE(("READ-LOCK file=%p, result=%d\n", pFile->h, res));
   return res;
 }
 
@@ -2849,7 +2849,7 @@ static int winUnlockReadLock(winFile *pFile){
     winLogError(SQLITE_IOERR_UNLOCK, pFile->lastErrno,
                 "winUnlockReadLock", pFile->zPath);
   }
-  OSTRACE(("READ-UNLOCK file=%p, rc=%s\n", pFile->h, sqlite3ErrName(res)));
+  OSTRACE(("READ-UNLOCK file=%p, result=%d\n", pFile->h, res));
   return res;
 }
 
@@ -2924,8 +2924,8 @@ static int winLock(sqlite3_file *id, int locktype){
       ** If you are using this code as a model for alternative VFSes, do not
       ** copy this retry logic.  It is a hack intended for Windows only.
       */
-      OSTRACE(("LOCK-PENDING-FAIL file=%p, count=%d, rc=%s\n",
-               pFile->h, cnt, sqlite3ErrName(res)));
+      OSTRACE(("LOCK-PENDING-FAIL file=%p, count=%d, result=%d\n",
+               pFile->h, cnt, res));
       if( cnt ) sqlite3_win32_sleep(1);
     }
     gotPendingLock = res;
@@ -3010,7 +3010,7 @@ static int winLock(sqlite3_file *id, int locktype){
 ** non-zero, otherwise zero.
 */
 static int winCheckReservedLock(sqlite3_file *id, int *pResOut){
-  int rc;
+  int res;
   winFile *pFile = (winFile*)id;
 
   SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
@@ -3018,17 +3018,17 @@ static int winCheckReservedLock(sqlite3_file *id, int *pResOut){
 
   assert( id!=0 );
   if( pFile->locktype>=RESERVED_LOCK ){
-    rc = 1;
-    OSTRACE(("TEST-WR-LOCK file=%p, rc=%d (local)\n", pFile->h, rc));
+    res = 1;
+    OSTRACE(("TEST-WR-LOCK file=%p, result=%d (local)\n", pFile->h, res));
   }else{
-    rc = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS,RESERVED_BYTE, 0, 1, 0);
-    if( rc ){
+    res = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS,RESERVED_BYTE, 0, 1, 0);
+    if( res ){
       winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
     }
-    rc = !rc;
-    OSTRACE(("TEST-WR-LOCK file=%p, rc=%d (remote)\n", pFile->h, rc));
+    res = !res;
+    OSTRACE(("TEST-WR-LOCK file=%p, result=%d (remote)\n", pFile->h, res));
   }
-  *pResOut = rc;
+  *pResOut = res;
   OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
            pFile->h, pResOut, *pResOut));
   return SQLITE_OK;
diff --git a/src/select.c b/src/select.c
index b3939ba64..ba6f6551a 100644
--- a/src/select.c
+++ b/src/select.c
@@ -4498,7 +4498,7 @@ static void explainSimpleCount(
   Index *pIdx                     /* Index used to optimize scan, or NULL */
 ){
   if( pParse->explain==2 ){
-    int bCover = (pIdx!=0 && (HasRowid(pTab) || pIdx->autoIndex!=2));
+    int bCover = (pIdx!=0 && (HasRowid(pTab) || !IsPrimaryKeyIndex(pIdx)));
     char *zEqp = sqlite3MPrintf(pParse->db, "SCAN TABLE %s%s%s",
         pTab->zName,
         bCover ? " USING COVERING INDEX " : "",
diff --git a/src/shell.c b/src/shell.c
index 08ed19544..9b45a2059 100644
--- a/src/shell.c
+++ b/src/shell.c
@@ -446,8 +446,9 @@ struct previous_mode_data {
 struct callback_data {
   sqlite3 *db;           /* The database */
   int echoOn;            /* True to echo input commands */
-  int autoEQP;           /* Run EXPLAIN QUERY PLAN prior to seach SQL statement */
+  int autoEQP;           /* Run EXPLAIN QUERY PLAN prior to seach SQL stmt */
   int statsOn;           /* True to display memory stats before each finalize */
+  int outCount;          /* Revert to stdout when reaching zero */
   int cnt;               /* Number of records displayed so far */
   FILE *out;             /* Write results here */
   FILE *traceOut;        /* Output for sqlite3_trace() */
@@ -878,7 +879,8 @@ static int shell_callback(void *pArg, int nArg, char **azArg, char **azCol, int
         }else if( aiType && aiType[i]==SQLITE_TEXT ){
           if( zSep[0] ) fprintf(p->out,"%s",zSep);
           output_quoted_string(p->out, azArg[i]);
-        }else if( aiType && (aiType[i]==SQLITE_INTEGER || aiType[i]==SQLITE_FLOAT) ){
+        }else if( aiType && (aiType[i]==SQLITE_INTEGER
+                             || aiType[i]==SQLITE_FLOAT) ){
           fprintf(p->out,"%s%s",zSep, azArg[i]);
         }else if( aiType && aiType[i]==SQLITE_BLOB && p->pStmt ){
           const void *pBlob = sqlite3_column_blob(p->pStmt, i);
@@ -1198,7 +1200,7 @@ static void explain_data_prepare(struct callback_data *p, sqlite3_stmt *pSql){
 
   const char *azNext[] = { "Next", "Prev", "VPrev", "VNext", "SorterNext",
                            "NextIfOpen", "PrevIfOpen", 0 };
-  const char *azYield[] = { "Yield", "SeekLt", "SeekGt", "RowSetRead", "Rewind", 0 };
+  const char *azYield[] = { "Yield", "SeekLT", "SeekGT", "RowSetRead", "Rewind", 0 };
   const char *azGoto[] = { "Goto", 0 };
 
   /* Try to figure out if this is really an EXPLAIN statement. If this
@@ -1570,17 +1572,17 @@ static int run_schema_dump_query(
 */
 static char zHelp[] =
   ".backup ?DB? FILE      Backup DB (default \"main\") to FILE\n"
-  ".bail ON|OFF           Stop after hitting an error.  Default OFF\n"
+  ".bail on|off           Stop after hitting an error.  Default OFF\n"
   ".clone NEWDB           Clone data into NEWDB from the existing database\n"
   ".databases             List names and files of attached databases\n"
   ".dump ?TABLE? ...      Dump the database in an SQL text format\n"
   "                         If TABLE specified, only dump tables matching\n"
   "                         LIKE pattern TABLE.\n"
-  ".echo ON|OFF           Turn command echo on or off\n"
+  ".echo on|off           Turn command echo on or off\n"
   ".exit                  Exit this program\n"
-  ".explain ?ON|OFF?      Turn output mode suitable for EXPLAIN on or off.\n"
+  ".explain ?on|off?      Turn output mode suitable for EXPLAIN on or off.\n"
   "                         With no args, it turns EXPLAIN on.\n"
-  ".header(s) ON|OFF      Turn display of headers on or off\n"
+  ".headers on|off        Turn display of headers on or off\n"
   ".help                  Show this message\n"
   ".import FILE TABLE     Import data from FILE into TABLE\n"
   ".indices ?TABLE?       Show names of all indices\n"
@@ -1603,9 +1605,9 @@ static char zHelp[] =
   "                         tabs     Tab-separated values\n"
   "                         tcl      TCL list elements\n"
   ".nullvalue STRING      Use STRING in place of NULL values\n"
+  ".once FILENAME         Output for the next SQL command only to FILENAME\n"
   ".open ?FILENAME?       Close existing database and reopen FILENAME\n"
-  ".output FILENAME       Send output to FILENAME\n"
-  ".output stdout         Send output to the screen\n"
+  ".output ?FILENAME?     Send output to FILENAME or stdout\n"
   ".print STRING...       Print literal STRING\n"
   ".prompt MAIN CONTINUE  Replace the standard prompts\n"
   ".quit                  Exit this program\n"
@@ -1616,19 +1618,19 @@ static char zHelp[] =
   "                         If TABLE specified, only show tables matching\n"
   "                         LIKE pattern TABLE.\n"
   ".separator STRING      Change separator used by output mode and .import\n"
+  ".shell CMD ARGS...     Run CMD ARGS... in a system shell\n"
   ".show                  Show the current values for various settings\n"
-  ".stats ON|OFF          Turn stats on or off\n"
+  ".stats on|off          Turn stats on or off\n"
+  ".system CMD ARGS...    Run CMD ARGS... in a system shell\n"
   ".tables ?TABLE?        List names of tables\n"
   "                         If TABLE specified, only list tables matching\n"
   "                         LIKE pattern TABLE.\n"
   ".timeout MS            Try opening locked tables for MS milliseconds\n"
+  ".timer on|off          Turn SQL timer on or off\n"
   ".trace FILE|off        Output each SQL statement as it is run\n"
   ".vfsname ?AUX?         Print the name of the VFS stack\n"
   ".width NUM1 NUM2 ...   Set column widths for \"column\" mode\n"
-;
-
-static char zTimerHelp[] =
-  ".timer ON|OFF          Turn the CPU timer measurement on or off\n"
+  "                         Negative values right-justify\n"
 ;
 
 /* Forward reference */
@@ -1672,6 +1674,7 @@ static void open_db(struct callback_data *p, int keepAlive){
 static void resolve_backslashes(char *z){
   int i, j;
   char c;
+  while( *z && *z!='\\' ) z++;
   for(i=j=0; (c = z[i])!=0; i++, j++){
     if( c=='\\' ){
       c = z[++i];
@@ -1697,7 +1700,7 @@ static void resolve_backslashes(char *z){
     }
     z[j] = c;
   }
-  z[j] = 0;
+  if( j<i ) z[j] = 0;
 }
 
 /*
@@ -2142,6 +2145,19 @@ static void tryToClone(struct callback_data *p, const char *zNewDb){
 }
 
 /*
+** Change the output file back to stdout
+*/
+static void output_reset(struct callback_data *p){
+  if( p->outfile[0]=='|' ){
+    pclose(p->out);
+  }else{
+    output_file_close(p->out);
+  }
+  p->outfile[0] = 0;
+  p->out = stdout;
+}
+
+/*
 ** If an input line begins with "." then invoke this routine to
 ** process that line.
 **
@@ -2239,8 +2255,13 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     sqlite3_close(pDest);
   }else
 
-  if( c=='b' && n>=3 && strncmp(azArg[0], "bail", n)==0 && nArg>1 && nArg<3 ){
-    bail_on_error = booleanValue(azArg[1]);
+  if( c=='b' && n>=3 && strncmp(azArg[0], "bail", n)==0 ){
+    if( nArg==2 ){
+      bail_on_error = booleanValue(azArg[1]);
+    }else{
+      fprintf(stderr, "Usage: .bail on|off\n");
+      rc = 1;
+    }
   }else
 
   /* The undocumented ".breakpoint" command causes a call to the no-op
@@ -2250,11 +2271,16 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     test_breakpoint();
   }else
 
-  if( c=='c' && strncmp(azArg[0], "clone", n)==0 && nArg>1 && nArg<3 ){
-    tryToClone(p, azArg[1]);
+  if( c=='c' && strncmp(azArg[0], "clone", n)==0 ){
+    if( nArg==2 ){
+      tryToClone(p, azArg[1]);
+    }else{
+      fprintf(stderr, "Usage: .clone FILENAME\n");
+      rc = 1;
+    }
   }else
 
-  if( c=='d' && n>1 && strncmp(azArg[0], "databases", n)==0 && nArg==1 ){
+  if( c=='d' && n>1 && strncmp(azArg[0], "databases", n)==0 ){
     struct callback_data data;
     char *zErrMsg = 0;
     open_db(p, 0);
@@ -2273,11 +2299,16 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     }
   }else
 
-  if( c=='d' && strncmp(azArg[0], "dump", n)==0 && nArg<3 ){
+  if( c=='d' && strncmp(azArg[0], "dump", n)==0 ){
     open_db(p, 0);
     /* When playing back a "dump", the content might appear in an order
     ** which causes immediate foreign key constraints to be violated.
     ** So disable foreign-key constraint enforcement to prevent problems. */
+    if( nArg!=1 && nArg!=2 ){
+      fprintf(stderr, "Usage: .dump ?LIKE-PATTERN?\n");
+      rc = 1;
+      goto meta_command_exit;
+    }
     fprintf(p->out, "PRAGMA foreign_keys=OFF;\n");
     fprintf(p->out, "BEGIN TRANSACTION;\n");
     p->writableSchema = 0;
@@ -2322,12 +2353,22 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     fprintf(p->out, p->nErr ? "ROLLBACK; -- due to errors\n" : "COMMIT;\n");
   }else
 
-  if( c=='e' && strncmp(azArg[0], "echo", n)==0 && nArg>1 && nArg<3 ){
-    p->echoOn = booleanValue(azArg[1]);
+  if( c=='e' && strncmp(azArg[0], "echo", n)==0 ){
+    if( nArg==2 ){
+      p->echoOn = booleanValue(azArg[1]);
+    }else{
+      fprintf(stderr, "Usage: .echo on|off\n");
+      rc = 1;
+    }
   }else
 
-  if( c=='e' && strncmp(azArg[0], "eqp", n)==0 && nArg>1 && nArg<3 ){
-    p->autoEQP = booleanValue(azArg[1]);
+  if( c=='e' && strncmp(azArg[0], "eqp", n)==0 ){
+    if( nArg==2 ){
+      p->autoEQP = booleanValue(azArg[1]);
+    }else{
+      fprintf(stderr, "Usage: .eqp on|off\n");
+      rc = 1;
+    }   
   }else
 
   if( c=='e' && strncmp(azArg[0], "exit", n)==0 ){
@@ -2335,7 +2376,7 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     rc = 2;
   }else
 
-  if( c=='e' && strncmp(azArg[0], "explain", n)==0 && nArg<3 ){
+  if( c=='e' && strncmp(azArg[0], "explain", n)==0 ){
     int val = nArg>=2 ? booleanValue(azArg[1]) : 1;
     if(val == 1) {
       if(!p->explainPrev.valid) {
@@ -2370,19 +2411,20 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     }
   }else
 
-  if( c=='h' && (strncmp(azArg[0], "header", n)==0 ||
-                 strncmp(azArg[0], "headers", n)==0) && nArg>1 && nArg<3 ){
-    p->showHeader = booleanValue(azArg[1]);
+  if( c=='h' && strncmp(azArg[0], "headers", n)==0 ){
+    if( nArg==2 ){
+      p->showHeader = booleanValue(azArg[1]);
+    }else{
+      fprintf(stderr, "Usage: .headers on|off\n");
+      rc = 1;
+    }
   }else
 
   if( c=='h' && strncmp(azArg[0], "help", n)==0 ){
-    fprintf(stderr,"%s",zHelp);
-    if( HAS_TIMER ){
-      fprintf(stderr,"%s",zTimerHelp);
-    }
+    fprintf(p->out, "%s", zHelp);
   }else
 
-  if( c=='i' && strncmp(azArg[0], "import", n)==0 && nArg==3 ){
+  if( c=='i' && strncmp(azArg[0], "import", n)==0 ){
     char *zTable = azArg[2];    /* Insert data into this table */
     char *zFile = azArg[1];     /* Name of file to extra content from */
     sqlite3_stmt *pStmt = NULL; /* A statement */
@@ -2395,6 +2437,10 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     CSVReader sCsv;             /* Reader context */
     int (*xCloser)(FILE*);      /* Procedure to close th3 connection */
 
+    if( nArg!=3 ){
+      fprintf(stderr, "Usage: .import FILE TABLE\n");
+      goto meta_command_exit;
+    }
     seenInterrupt = 0;
     memset(&sCsv, 0, sizeof(sCsv));
     open_db(p, 0);
@@ -2533,7 +2579,7 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     if( needCommit ) sqlite3_exec(db, "COMMIT", 0, 0, 0);
   }else
 
-  if( c=='i' && strncmp(azArg[0], "indices", n)==0 && nArg<3 ){
+  if( c=='i' && strncmp(azArg[0], "indices", n)==0 ){
     struct callback_data data;
     char *zErrMsg = 0;
     open_db(p, 0);
@@ -2550,7 +2596,7 @@ static int do_meta_command(char *zLine, struct callback_data *p){
         "ORDER BY 1",
         callback, &data, &zErrMsg
       );
-    }else{
+    }else if( nArg==2 ){
       zShellStatic = azArg[1];
       rc = sqlite3_exec(p->db,
         "SELECT name FROM sqlite_master "
@@ -2562,6 +2608,10 @@ static int do_meta_command(char *zLine, struct callback_data *p){
         callback, &data, &zErrMsg
       );
       zShellStatic = 0;
+    }else{
+      fprintf(stderr, "Usage: .indices ?LIKE-PATTERN?\n");
+      rc = 1;
+      goto meta_command_exit;
     }
     if( zErrMsg ){
       fprintf(stderr,"Error: %s\n", zErrMsg);
@@ -2597,9 +2647,14 @@ static int do_meta_command(char *zLine, struct callback_data *p){
 #endif
 
 #ifndef SQLITE_OMIT_LOAD_EXTENSION
-  if( c=='l' && strncmp(azArg[0], "load", n)==0 && nArg>=2 ){
+  if( c=='l' && strncmp(azArg[0], "load", n)==0 ){
     const char *zFile, *zProc;
     char *zErrMsg = 0;
+    if( nArg<2 ){
+      fprintf(stderr, "Usage: .load FILE ?ENTRYPOINT?\n");
+      rc = 1;
+      goto meta_command_exit;
+    }
     zFile = azArg[1];
     zProc = nArg>=3 ? azArg[2] : 0;
     open_db(p, 0);
@@ -2612,38 +2667,41 @@ static int do_meta_command(char *zLine, struct callback_data *p){
   }else
 #endif
 
-  if( c=='l' && strncmp(azArg[0], "log", n)==0 && nArg>=2 ){
-    const char *zFile = azArg[1];
-    output_file_close(p->pLog);
-    p->pLog = output_file_open(zFile);
+  if( c=='l' && strncmp(azArg[0], "log", n)==0 ){
+    if( nArg!=2 ){
+      fprintf(stderr, "Usage: .log FILENAME\n");
+      rc = 1;
+    }else{
+      const char *zFile = azArg[1];
+      output_file_close(p->pLog);
+      p->pLog = output_file_open(zFile);
+    }
   }else
 
-  if( c=='m' && strncmp(azArg[0], "mode", n)==0 && nArg==2 ){
-    int n2 = strlen30(azArg[1]);
-    if( (n2==4 && strncmp(azArg[1],"line",n2)==0)
-        ||
-        (n2==5 && strncmp(azArg[1],"lines",n2)==0) ){
+  if( c=='m' && strncmp(azArg[0], "mode", n)==0 ){
+    const char *zMode = nArg>=2 ? azArg[1] : "";
+    int n2 = (int)strlen(zMode);
+    int c2 = zMode[0];
+    if( c2=='l' && n2>2 && strncmp(azArg[1],"lines",n2)==0 ){
       p->mode = MODE_Line;
-    }else if( (n2==6 && strncmp(azArg[1],"column",n2)==0)
-              ||
-              (n2==7 && strncmp(azArg[1],"columns",n2)==0) ){
+    }else if( c2=='c' && strncmp(azArg[1],"columns",n2)==0 ){
       p->mode = MODE_Column;
-    }else if( n2==4 && strncmp(azArg[1],"list",n2)==0 ){
+    }else if( c2=='l' && n2>2 && strncmp(azArg[1],"list",n2)==0 ){
       p->mode = MODE_List;
-    }else if( n2==4 && strncmp(azArg[1],"html",n2)==0 ){
+    }else if( c2=='h' && strncmp(azArg[1],"html",n2)==0 ){
       p->mode = MODE_Html;
-    }else if( n2==3 && strncmp(azArg[1],"tcl",n2)==0 ){
+    }else if( c2=='t' && strncmp(azArg[1],"tcl",n2)==0 ){
       p->mode = MODE_Tcl;
       sqlite3_snprintf(sizeof(p->separator), p->separator, " ");
-    }else if( n2==3 && strncmp(azArg[1],"csv",n2)==0 ){
+    }else if( c2=='c' && strncmp(azArg[1],"csv",n2)==0 ){
       p->mode = MODE_Csv;
       sqlite3_snprintf(sizeof(p->separator), p->separator, ",");
-    }else if( n2==4 && strncmp(azArg[1],"tabs",n2)==0 ){
+    }else if( c2=='t' && strncmp(azArg[1],"tabs",n2)==0 ){
       p->mode = MODE_List;
       sqlite3_snprintf(sizeof(p->separator), p->separator, "\t");
-    }else if( n2==6 && strncmp(azArg[1],"insert",n2)==0 ){
+    }else if( c2=='i' && strncmp(azArg[1],"insert",n2)==0 ){
       p->mode = MODE_Insert;
-      set_table_name(p, "table");
+      set_table_name(p, nArg>=3 ? azArg[2] : "table");
     }else {
       fprintf(stderr,"Error: mode should be one of: "
          "column csv html insert line list tabs tcl\n");
@@ -2651,23 +2709,16 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     }
   }else
 
-  if( c=='m' && strncmp(azArg[0], "mode", n)==0 && nArg==3 ){
-    int n2 = strlen30(azArg[1]);
-    if( n2==6 && strncmp(azArg[1],"insert",n2)==0 ){
-      p->mode = MODE_Insert;
-      set_table_name(p, azArg[2]);
-    }else {
-      fprintf(stderr, "Error: invalid arguments: "
-        " \"%s\". Enter \".help\" for help\n", azArg[2]);
+  if( c=='n' && strncmp(azArg[0], "nullvalue", n)==0 ){
+    if( nArg==2 ){
+      sqlite3_snprintf(sizeof(p->nullvalue), p->nullvalue,
+                       "%.*s", (int)ArraySize(p->nullvalue)-1, azArg[1]);
+    }else{
+      fprintf(stderr, "Usage: .nullvalue STRING\n");
       rc = 1;
     }
   }else
 
-  if( c=='n' && strncmp(azArg[0], "nullvalue", n)==0 && nArg==2 ) {
-    sqlite3_snprintf(sizeof(p->nullvalue), p->nullvalue,
-                     "%.*s", (int)ArraySize(p->nullvalue)-1, azArg[1]);
-  }else
-
   if( c=='o' && strncmp(azArg[0], "open", n)==0 && n>=2 ){
     sqlite3 *savedDb = p->db;
     const char *zSavedFilename = p->zDbFilename;
@@ -2688,32 +2739,45 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     }
   }else
 
-  if( c=='o' && strncmp(azArg[0], "output", n)==0 && nArg==2 ){
-    if( p->outfile[0]=='|' ){
-      pclose(p->out);
+  if( c=='o'
+   && (strncmp(azArg[0], "output", n)==0 || strncmp(azArg[0], "once", n)==0)
+  ){
+    const char *zFile = nArg>=2 ? azArg[1] : "stdout";
+    if( nArg>2 ){
+      fprintf(stderr, "Usage: .%s FILE\n", azArg[0]);
+      rc = 1;
+      goto meta_command_exit;
+    }
+    if( n>1 && strncmp(azArg[0], "once", n)==0 ){
+      if( nArg<2 ){
+        fprintf(stderr, "Usage: .once FILE\n");
+        rc = 1;
+        goto meta_command_exit;
+      }
+      p->outCount = 2;
     }else{
-      output_file_close(p->out);
+      p->outCount = 0;
     }
-    p->outfile[0] = 0;
-    if( azArg[1][0]=='|' ){
-      p->out = popen(&azArg[1][1], "w");
+    output_reset(p);
+    if( zFile[0]=='|' ){
+      p->out = popen(zFile + 1, "w");
       if( p->out==0 ){
-        fprintf(stderr,"Error: cannot open pipe \"%s\"\n", &azArg[1][1]);
+        fprintf(stderr,"Error: cannot open pipe \"%s\"\n", zFile + 1);
         p->out = stdout;
         rc = 1;
       }else{
-        sqlite3_snprintf(sizeof(p->outfile), p->outfile, "%s", azArg[1]);
+        sqlite3_snprintf(sizeof(p->outfile), p->outfile, "%s", zFile);
       }
     }else{
-      p->out = output_file_open(azArg[1]);
+      p->out = output_file_open(zFile);
       if( p->out==0 ){
-        if( strcmp(azArg[1],"off")!=0 ){
-          fprintf(stderr,"Error: cannot write to \"%s\"\n", azArg[1]);
+        if( strcmp(zFile,"off")!=0 ){
+          fprintf(stderr,"Error: cannot write to \"%s\"\n", zFile);
         }
         p->out = stdout;
         rc = 1;
       } else {
-        sqlite3_snprintf(sizeof(p->outfile), p->outfile, "%s", azArg[1]);
+        sqlite3_snprintf(sizeof(p->outfile), p->outfile, "%s", zFile);
       }
     }
   }else
@@ -2727,7 +2791,7 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     fprintf(p->out, "\n");
   }else
 
-  if( c=='p' && strncmp(azArg[0], "prompt", n)==0 && (nArg==2 || nArg==3)){
+  if( c=='p' && strncmp(azArg[0], "prompt", n)==0 ){
     if( nArg >= 2) {
       strncpy(mainPrompt,azArg[1],(int)ArraySize(mainPrompt)-1);
     }
@@ -2736,12 +2800,18 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     }
   }else
 
-  if( c=='q' && strncmp(azArg[0], "quit", n)==0 && nArg==1 ){
+  if( c=='q' && strncmp(azArg[0], "quit", n)==0 ){
     rc = 2;
   }else
 
-  if( c=='r' && n>=3 && strncmp(azArg[0], "read", n)==0 && nArg==2 ){
-    FILE *alt = fopen(azArg[1], "rb");
+  if( c=='r' && n>=3 && strncmp(azArg[0], "read", n)==0 ){
+    FILE *alt;
+    if( nArg!=2 ){
+      fprintf(stderr, "Usage: .read FILE\n");
+      rc = 1;
+      goto meta_command_exit;
+    }
+    alt = fopen(azArg[1], "rb");
     if( alt==0 ){
       fprintf(stderr,"Error: cannot open \"%s\"\n", azArg[1]);
       rc = 1;
@@ -2751,7 +2821,7 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     }
   }else
 
-  if( c=='r' && n>=3 && strncmp(azArg[0], "restore", n)==0 && nArg>1 && nArg<4){
+  if( c=='r' && n>=3 && strncmp(azArg[0], "restore", n)==0 ){
     const char *zSrcFile;
     const char *zDb;
     sqlite3 *pSrc;
@@ -2761,9 +2831,13 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     if( nArg==2 ){
       zSrcFile = azArg[1];
       zDb = "main";
-    }else{
+    }else if( nArg==3 ){
       zSrcFile = azArg[2];
       zDb = azArg[1];
+    }else{
+      fprintf(stderr, "Usage: .restore ?DB? FILE\n");
+      rc = 1;
+      goto meta_command_exit;
     }
     rc = sqlite3_open(zSrcFile, &pSrc);
     if( rc!=SQLITE_OK ){
@@ -2798,14 +2872,14 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     sqlite3_close(pSrc);
   }else
 
-  if( c=='s' && strncmp(azArg[0], "schema", n)==0 && nArg<3 ){
+  if( c=='s' && strncmp(azArg[0], "schema", n)==0 ){
     struct callback_data data;
     char *zErrMsg = 0;
     open_db(p, 0);
     memcpy(&data, p, sizeof(data));
     data.showHeader = 0;
     data.mode = MODE_Semi;
-    if( nArg>1 ){
+    if( nArg==2 ){
       int i;
       for(i=0; azArg[1][i]; i++) azArg[1][i] = ToLower(azArg[1][i]);
       if( strcmp(azArg[1],"sqlite_master")==0 ){
@@ -2849,7 +2923,7 @@ static int do_meta_command(char *zLine, struct callback_data *p){
           callback, &data, &zErrMsg);
         zShellStatic = 0;
       }
-    }else{
+    }else if( nArg==1 ){
       rc = sqlite3_exec(p->db,
          "SELECT sql FROM "
          "  (SELECT sql sql, type type, tbl_name tbl_name, name name, rowid x"
@@ -2859,6 +2933,10 @@ static int do_meta_command(char *zLine, struct callback_data *p){
          "ORDER BY rowid",
          callback, &data, &zErrMsg
       );
+    }else{
+      fprintf(stderr, "Usage: .schema ?LIKE-PATTERN?\n");
+      rc = 1;
+      goto meta_command_exit;
     }
     if( zErrMsg ){
       fprintf(stderr,"Error: %s\n", zErrMsg);
@@ -2888,20 +2966,49 @@ static int do_meta_command(char *zLine, struct callback_data *p){
       for(i=1; i<nArg; i++){
         char zBuf[200];
         v = integerValue(azArg[i]);
-        sqlite3_snprintf(sizeof(zBuf), zBuf, "%s: %lld 0x%llx\n", azArg[i], v, v);
+        sqlite3_snprintf(sizeof(zBuf),zBuf,"%s: %lld 0x%llx\n", azArg[i],v,v);
         fprintf(p->out, "%s", zBuf);
       }
     }
   }else
 #endif
 
-  if( c=='s' && strncmp(azArg[0], "separator", n)==0 && nArg==2 ){
-    sqlite3_snprintf(sizeof(p->separator), p->separator,
-                     "%.*s", (int)sizeof(p->separator)-1, azArg[1]);
+  if( c=='s' && strncmp(azArg[0], "separator", n)==0 ){
+    if( nArg==2 ){
+      sqlite3_snprintf(sizeof(p->separator), p->separator,
+                       "%.*s", (int)sizeof(p->separator)-1, azArg[1]);
+    }else{
+      fprintf(stderr, "Usage: .separator STRING\n");
+      rc = 1;
+    }
+  }else
+
+  if( c=='s'
+   && (strncmp(azArg[0], "shell", n)==0 || strncmp(azArg[0],"system",n)==0)
+  ){
+    char *zCmd;
+    int i;
+    if( nArg<2 ){
+      fprintf(stderr, "Usage: .system COMMAND\n");
+      rc = 1;
+      goto meta_command_exit;
+    }
+    zCmd = sqlite3_mprintf(strchr(azArg[1],' ')==0?"%s":"\"%s\"", azArg[1]);
+    for(i=2; i<nArg; i++){
+      zCmd = sqlite3_mprintf(strchr(azArg[i],' ')==0?"%z %s":"%z \"%s\"",
+                             zCmd, azArg[i]);
+    }
+    system(zCmd);
+    sqlite3_free(zCmd);
   }else
 
-  if( c=='s' && strncmp(azArg[0], "show", n)==0 && nArg==1 ){
+  if( c=='s' && strncmp(azArg[0], "show", n)==0 ){
     int i;
+    if( nArg!=1 ){
+      fprintf(stderr, "Usage: .show\n");
+      rc = 1;
+      goto meta_command_exit;
+    }
     fprintf(p->out,"%9.9s: %s\n","echo", p->echoOn ? "on" : "off");
     fprintf(p->out,"%9.9s: %s\n","eqp", p->autoEQP ? "on" : "off");
     fprintf(p->out,"%9.9s: %s\n","explain", p->explainPrev.valid ? "on" :"off");
@@ -2923,11 +3030,16 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     fprintf(p->out,"\n");
   }else
 
-  if( c=='s' && strncmp(azArg[0], "stats", n)==0 && nArg>1 && nArg<3 ){
-    p->statsOn = booleanValue(azArg[1]);
+  if( c=='s' && strncmp(azArg[0], "stats", n)==0 ){
+    if( nArg==2 ){
+      p->statsOn = booleanValue(azArg[1]);
+    }else{
+      fprintf(stderr, "Usage: .stats on|off\n");
+      rc = 1;
+    }
   }else
 
-  if( c=='t' && n>1 && strncmp(azArg[0], "tables", n)==0 && nArg<3 ){
+  if( c=='t' && n>1 && strncmp(azArg[0], "tables", n)==0 ){
     sqlite3_stmt *pStmt;
     char **azResult;
     int nRow, nAlloc;
@@ -3133,20 +3245,32 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     }
   }else
 
-  if( c=='t' && n>4 && strncmp(azArg[0], "timeout", n)==0 && nArg==2 ){
+  if( c=='t' && n>4 && strncmp(azArg[0], "timeout", n)==0 ){
     open_db(p, 0);
-    sqlite3_busy_timeout(p->db, (int)integerValue(azArg[1]));
+    sqlite3_busy_timeout(p->db, nArg>=2 ? (int)integerValue(azArg[1]) : 0);
   }else
     
-  if( HAS_TIMER && c=='t' && n>=5 && strncmp(azArg[0], "timer", n)==0
-   && nArg==2
-  ){
-    enableTimer = booleanValue(azArg[1]);
+  if( c=='t' && n>=5 && strncmp(azArg[0], "timer", n)==0 ){
+    if( nArg==2 ){
+      enableTimer = booleanValue(azArg[1]);
+      if( enableTimer && !HAS_TIMER ){
+        fprintf(stderr, "Error: timer not available on this system.\n");
+        enableTimer = 0;
+      }
+    }else{
+      fprintf(stderr, "Usage: .timer on|off\n");
+      rc = 1;
+    }
   }else
   
-  if( c=='t' && strncmp(azArg[0], "trace", n)==0 && nArg>1 ){
+  if( c=='t' && strncmp(azArg[0], "trace", n)==0 ){
     open_db(p, 0);
     output_file_close(p->traceOut);
+    if( nArg!=2 ){
+      fprintf(stderr, "Usage: .trace FILE|off\n");
+      rc = 1;
+      goto meta_command_exit;
+    }
     p->traceOut = output_file_open(azArg[1]);
 #if !defined(SQLITE_OMIT_TRACE) && !defined(SQLITE_OMIT_FLOATING_POINT)
     if( p->traceOut==0 ){
@@ -3177,11 +3301,11 @@ static int do_meta_command(char *zLine, struct callback_data *p){
 #if defined(SQLITE_DEBUG) && defined(SQLITE_ENABLE_WHERETRACE)
   if( c=='w' && strncmp(azArg[0], "wheretrace", n)==0 ){
     extern int sqlite3WhereTrace;
-    sqlite3WhereTrace = booleanValue(azArg[1]);
+    sqlite3WhereTrace = nArg>=2 ? booleanValue(azArg[1]) : 0xff;
   }else
 #endif
 
-  if( c=='w' && strncmp(azArg[0], "width", n)==0 && nArg>1 ){
+  if( c=='w' && strncmp(azArg[0], "width", n)==0 ){
     int j;
     assert( nArg<=ArraySize(azArg) );
     for(j=1; j<nArg && j<ArraySize(p->colWidth); j++){
@@ -3195,6 +3319,11 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     rc = 1;
   }
 
+meta_command_exit:
+  if( p->outCount ){
+    p->outCount--;
+    if( p->outCount==0 ) output_reset(p);
+  }
   return rc;
 }
 
@@ -3362,6 +3491,10 @@ static int process_input(struct callback_data *p, FILE *in){
         errCnt++;
       }
       nSql = 0;
+      if( p->outCount ){
+        output_reset(p);
+        p->outCount = 0;
+      }
     }else if( nSql && _all_whitespace(zSql) ){
       if( p->echoOn ) printf("%s\n", zSql);
       nSql = 0;
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 9b4215dd8..061c9e2bc 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -1702,7 +1702,7 @@ struct Index {
   u16 nKeyCol;             /* Number of columns forming the key */
   u16 nColumn;             /* Number of columns stored in the index */
   u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
-  unsigned autoIndex:2;    /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
+  unsigned idxType:2;      /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
   unsigned bUnordered:1;   /* Use this index for == or IN queries only */
   unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
   unsigned isResized:1;    /* True if resizeIndexObject() has been called */
@@ -1716,6 +1716,16 @@ struct Index {
 };
 
 /*
+** Allowed values for Index.idxType
+*/
+#define SQLITE_IDXTYPE_APPDEF      0   /* Created using CREATE INDEX */
+#define SQLITE_IDXTYPE_UNIQUE      1   /* Implements a UNIQUE constraint */
+#define SQLITE_IDXTYPE_PRIMARYKEY  2   /* Is the PRIMARY KEY for the table */
+
+/* Return true if index X is a PRIMARY KEY index */
+#define IsPrimaryKeyIndex(X)  ((X)->idxType==SQLITE_IDXTYPE_PRIMARYKEY)
+
+/*
 ** Each sample stored in the sqlite_stat3 table is represented in memory 
 ** using a structure of this type.  See documentation at the top of the
 ** analyze.c source file for additional information.
diff --git a/src/update.c b/src/update.c
index a1082068e..0c8a4202e 100644
--- a/src/update.c
+++ b/src/update.c
@@ -187,7 +187,7 @@ void sqlite3Update(
   iIdxCur = iDataCur+1;
   pPk = HasRowid(pTab) ? 0 : sqlite3PrimaryKeyIndex(pTab);
   for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){
-    if( pIdx->autoIndex==2 && pPk!=0 ){
+    if( IsPrimaryKeyIndex(pIdx) && pPk!=0 ){
       iDataCur = pParse->nTab;
       pTabList->a[0].iCursor = iDataCur;
     }
diff --git a/src/vdbe.c b/src/vdbe.c
index ebb7478db..20d5c46b5 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -6342,7 +6342,7 @@ case OP_Init: {          /* jump */
   if( zTrace ){
     int i;
     for(i=0; i<db->nDb; i++){
-      if( MASKBIT(i) & p->btreeMask)==0 ) continue;
+      if( (MASKBIT(i) & p->btreeMask)==0 ) continue;
       sqlite3_file_control(db, db->aDb[i].zName, SQLITE_FCNTL_TRACE, zTrace);
     }
   }
diff --git a/src/vdbesort.c b/src/vdbesort.c
index d1b726b72..d3690244c 100644
--- a/src/vdbesort.c
+++ b/src/vdbesort.c
@@ -350,7 +350,6 @@ static int vdbeSorterIterInit(
       rc = sqlite3OsRead(
           pSorter->pTemp1, &pIter->aBuffer[iBuf], nRead, iStart
       );
-      assert( rc!=SQLITE_IOERR_SHORT_READ );
     }
 
     if( rc==SQLITE_OK ){
diff --git a/src/where.c b/src/where.c
index b9385a5ec..25c1c0414 100644
--- a/src/where.c
+++ b/src/where.c
@@ -2722,7 +2722,7 @@ static void explainOneScan(
       Index *pIdx = pLoop->u.btree.pIndex;
       char *zWhere = explainIndexRange(db, pLoop, pItem->pTab);
       assert( !(flags&WHERE_AUTO_INDEX) || (flags&WHERE_IDX_ONLY) );
-      if( !HasRowid(pItem->pTab) && pIdx->autoIndex==2 ){
+      if( !HasRowid(pItem->pTab) && IsPrimaryKeyIndex(pIdx) ){
         zFmt = zWhere ? "%s USING PRIMARY KEY%.0s%s" : "%s%.0s%s";
       }else if( flags & WHERE_AUTO_INDEX ){
         zFmt = "%s USING AUTOMATIC COVERING INDEX%.0s%s";
@@ -3223,7 +3223,7 @@ static Bitmask codeOneLoopStart(
       sqlite3VdbeAddOp2(v, OP_IdxRowid, iIdxCur, iRowidReg);
       sqlite3ExprCacheStore(pParse, iCur, -1, iRowidReg);
       sqlite3VdbeAddOp2(v, OP_Seek, iCur, iRowidReg);  /* Deferred seek */
-    }else{
+    }else if( iCur!=iIdxCur ){
       Index *pPk = sqlite3PrimaryKeyIndex(pIdx->pTable);
       iRowidReg = sqlite3GetTempRange(pParse, pPk->nKeyCol);
       for(j=0; j<pPk->nKeyCol; j++){
@@ -3293,6 +3293,10 @@ static Bitmask codeOneLoopStart(
     **
     **       B: <after the loop>
     **
+    ** Added 2014-05-26: If the table is a WITHOUT ROWID table, then
+    ** use an ephermeral index instead of a RowSet to record the primary
+    ** keys of the rows we have already seen.
+    **
     */
     WhereClause *pOrWc;    /* The OR-clause broken out into subterms */
     SrcList *pOrTab;       /* Shortened table list or OR-clause generation */
@@ -3307,6 +3311,7 @@ static Bitmask codeOneLoopStart(
     int untestedTerms = 0;             /* Some terms not completely tested */
     int ii;                            /* Loop counter */
     Expr *pAndExpr = 0;                /* An ".. AND (...)" expression */
+    Table *pTab = pTabItem->pTab;
    
     pTerm = pLoop->aLTerm[0];
     assert( pTerm!=0 );
@@ -3339,7 +3344,8 @@ static Bitmask codeOneLoopStart(
     }
 
     /* Initialize the rowset register to contain NULL. An SQL NULL is 
-    ** equivalent to an empty rowset.
+    ** equivalent to an empty rowset.  Or, create an ephermeral index
+    ** capable of holding primary keys in the case of a WITHOUT ROWID.
     **
     ** Also initialize regReturn to contain the address of the instruction 
     ** immediately following the OP_Return at the bottom of the loop. This
@@ -3350,9 +3356,16 @@ static Bitmask codeOneLoopStart(
     ** called on an uninitialized cursor.
     */
     if( (pWInfo->wctrlFlags & WHERE_DUPLICATES_OK)==0 ){
-      regRowset = ++pParse->nMem;
+      if( HasRowid(pTab) ){
+        regRowset = ++pParse->nMem;
+        sqlite3VdbeAddOp2(v, OP_Null, 0, regRowset);
+      }else{
+        Index *pPk = sqlite3PrimaryKeyIndex(pTab);
+        regRowset = pParse->nTab++;
+        sqlite3VdbeAddOp2(v, OP_OpenEphemeral, regRowset, pPk->nKeyCol);
+        sqlite3VdbeSetP4KeyInfo(pParse, pPk);
+      }
       regRowid = ++pParse->nMem;
-      sqlite3VdbeAddOp2(v, OP_Null, 0, regRowset);
     }
     iRetInit = sqlite3VdbeAddOp2(v, OP_Integer, 0, regReturn);
 
@@ -3388,11 +3401,16 @@ static Bitmask codeOneLoopStart(
       }
     }
 
+    /* Run a separate WHERE clause for each term of the OR clause.  After
+    ** eliminating duplicates from other WHERE clauses, the action for each
+    ** sub-WHERE clause is to to invoke the main loop body as a subroutine.
+    */
     for(ii=0; ii<pOrWc->nTerm; ii++){
       WhereTerm *pOrTerm = &pOrWc->a[ii];
       if( pOrTerm->leftCursor==iCur || (pOrTerm->eOperator & WO_AND)!=0 ){
-        WhereInfo *pSubWInfo;          /* Info for single OR-term scan */
-        Expr *pOrExpr = pOrTerm->pExpr;
+        WhereInfo *pSubWInfo;           /* Info for single OR-term scan */
+        Expr *pOrExpr = pOrTerm->pExpr; /* Current OR clause term */
+        int j1 = 0;                     /* Address of jump operation */
         if( pAndExpr && !ExprHasProperty(pOrExpr, EP_FromJoin) ){
           pAndExpr->pLeft = pOrExpr;
           pOrExpr = pAndExpr;
@@ -3407,17 +3425,63 @@ static Bitmask codeOneLoopStart(
           explainOneScan(
               pParse, pOrTab, &pSubWInfo->a[0], iLevel, pLevel->iFrom, 0
           );
+          /* This is the sub-WHERE clause body.  First skip over
+          ** duplicate rows from prior sub-WHERE clauses, and record the
+          ** rowid (or PRIMARY KEY) for the current row so that the same
+          ** row will be skipped in subsequent sub-WHERE clauses.
+          */
           if( (pWInfo->wctrlFlags & WHERE_DUPLICATES_OK)==0 ){
-            int iSet = ((ii==pOrWc->nTerm-1)?-1:ii);
             int r;
-            r = sqlite3ExprCodeGetColumn(pParse, pTabItem->pTab, -1, iCur, 
-                                         regRowid, 0);
-            sqlite3VdbeAddOp4Int(v, OP_RowSetTest, regRowset,
-                                 sqlite3VdbeCurrentAddr(v)+2, r, iSet);
-            VdbeCoverage(v);
+            int iSet = ((ii==pOrWc->nTerm-1)?-1:ii);
+            if( HasRowid(pTab) ){
+              r = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iCur, regRowid, 0);
+              j1 = sqlite3VdbeAddOp4Int(v, OP_RowSetTest, regRowset, 0, r,iSet);
+              VdbeCoverage(v);
+            }else{
+              Index *pPk = sqlite3PrimaryKeyIndex(pTab);
+              int nPk = pPk->nKeyCol;
+              int iPk;
+
+              /* Read the PK into an array of temp registers. */
+              r = sqlite3GetTempRange(pParse, nPk);
+              for(iPk=0; iPk<nPk; iPk++){
+                int iCol = pPk->aiColumn[iPk];
+                sqlite3ExprCodeGetColumn(pParse, pTab, iCol, iCur, r+iPk, 0);
+              }
+
+              /* Check if the temp table already contains this key. If so,
+              ** the row has already been included in the result set and
+              ** can be ignored (by jumping past the Gosub below). Otherwise,
+              ** insert the key into the temp table and proceed with processing
+              ** the row.
+              **
+              ** Use some of the same optimizations as OP_RowSetTest: If iSet
+              ** is zero, assume that the key cannot already be present in
+              ** the temp table. And if iSet is -1, assume that there is no 
+              ** need to insert the key into the temp table, as it will never 
+              ** be tested for.  */ 
+              if( iSet ){
+                j1 = sqlite3VdbeAddOp4Int(v, OP_Found, regRowset, 0, r, nPk);
+                VdbeCoverage(v);
+              }
+              if( iSet>=0 ){
+                sqlite3VdbeAddOp3(v, OP_MakeRecord, r, nPk, regRowid);
+                sqlite3VdbeAddOp3(v, OP_IdxInsert, regRowset, regRowid, 0);
+                if( iSet ) sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
+              }
+
+              /* Release the array of temp registers */
+              sqlite3ReleaseTempRange(pParse, r, nPk);
+            }
           }
+
+          /* Invoke the main loop body as a subroutine */
           sqlite3VdbeAddOp2(v, OP_Gosub, regReturn, iLoopBody);
 
+          /* Jump here (skipping the main loop body subroutine) if the
+          ** current sub-WHERE row is a duplicate from prior sub-WHEREs. */
+          if( j1 ) sqlite3VdbeJumpHere(v, j1);
+
           /* The pSubWInfo->untestedTerms flag means that this OR term
           ** contained one or more AND term from a notReady table.  The
           ** terms from the notReady table could not be tested and will
@@ -3441,6 +3505,7 @@ static Bitmask codeOneLoopStart(
           assert( (pSubLoop->wsFlags & WHERE_AUTO_INDEX)==0 );
           if( (pSubLoop->wsFlags & WHERE_INDEXED)!=0
            && (ii==0 || pSubLoop->u.btree.pIndex==pCov)
+           && (HasRowid(pTab) || !IsPrimaryKeyIndex(pSubLoop->u.btree.pIndex))
           ){
             assert( pSubWInfo->a[0].iIdxCur==iCovCur );
             pCov = pSubLoop->u.btree.pIndex;
@@ -4766,7 +4831,6 @@ static int whereLoopAddOr(WhereLoopBuilder *pBuilder, Bitmask mExtra){
   pNew = pBuilder->pNew;
   memset(&sSum, 0, sizeof(sSum));
   pItem = pWInfo->pTabList->a + pNew->iTab;
-  if( !HasRowid(pItem->pTab) ) return SQLITE_OK;
   iCur = pItem->iCursor;
 
   for(pTerm=pWC->a; pTerm<pWCEnd && rc==SQLITE_OK; pTerm++){
@@ -6015,7 +6079,14 @@ WhereInfo *sqlite3WhereBegin(
       int op = OP_OpenRead;
       /* iIdxCur is always set if to a positive value if ONEPASS is possible */
       assert( iIdxCur!=0 || (pWInfo->wctrlFlags & WHERE_ONEPASS_DESIRED)==0 );
-      if( pWInfo->okOnePass ){
+      if( !HasRowid(pTab) && IsPrimaryKeyIndex(pIx)
+       && (wctrlFlags & WHERE_ONETABLE_ONLY)!=0
+      ){
+        /* This is one term of an OR-optimization using the PRIMARY KEY of a
+        ** WITHOUT ROWID table.  No need for a separate index */
+        iIndexCur = pLevel->iTabCur;
+        op = 0;
+      }else if( pWInfo->okOnePass ){
         Index *pJ = pTabItem->pTab->pIndex;
         iIndexCur = iIdxCur;
         assert( wctrlFlags & WHERE_ONEPASS_DESIRED );
@@ -6033,9 +6104,11 @@ WhereInfo *sqlite3WhereBegin(
       pLevel->iIdxCur = iIndexCur;
       assert( pIx->pSchema==pTab->pSchema );
       assert( iIndexCur>=0 );
-      sqlite3VdbeAddOp3(v, op, iIndexCur, pIx->tnum, iDb);
-      sqlite3VdbeSetP4KeyInfo(pParse, pIx);
-      VdbeComment((v, "%s", pIx->zName));
+      if( op ){
+        sqlite3VdbeAddOp3(v, op, iIndexCur, pIx->tnum, iDb);
+        sqlite3VdbeSetP4KeyInfo(pParse, pIx);
+        VdbeComment((v, "%s", pIx->zName));
+      }
     }
     if( iDb>=0 ) sqlite3CodeVerifySchema(pParse, iDb);
     notReady &= ~getMask(&pWInfo->sMaskSet, pTabItem->iCursor);