Allow the sessions module to be configured to capture changes from tables with no explicit PRIMARY KEY.

FossilOrigin-Name: 5d4431bc44e206f48f3bcc1f51399b38bd4cb418e7e50a37495475fb8da04646

1 files changed, 180 insertions, 71 deletions

diff --git a/ext/session/sqlite3session.c b/ext/session/sqlite3session.c
index 225d0316a..e601a4ae7 100644
--- a/ext/session/sqlite3session.c
+++ b/ext/session/sqlite3session.c
@@ -25,6 +25,8 @@ typedef struct SessionInput SessionInput;
 # endif
 #endif
 
+#define SESSIONS_ROWID "_rowid_"
+
 static int sessions_strm_chunk_size = SESSIONS_STRM_CHUNK_SIZE;
 
 typedef struct SessionHook SessionHook;
@@ -46,6 +48,7 @@ struct sqlite3_session {
   int bEnable;                    /* True if currently recording */
   int bIndirect;                  /* True if all changes are indirect */
   int bAutoAttach;                /* True to auto-attach tables */
+  int bImplicitPK;                /* True to handle tables with implicit PK */
   int rc;                         /* Non-zero if an error has occurred */
   void *pFilterCtx;               /* First argument to pass to xTableFilter */
   int (*xTableFilter)(void *pCtx, const char *zTab);
@@ -122,6 +125,7 @@ struct SessionTable {
   char *zName;                    /* Local name of table */
   int nCol;                       /* Number of columns in table zName */
   int bStat1;                     /* True if this is sqlite_stat1 */
+  int bRowid;                     /* True if this table uses rowid for PK */
   const char **azCol;             /* Column names */
   u8 *abPK;                       /* Array of primary key flags */
   int nEntry;                     /* Total number of entries in hash table */
@@ -514,6 +518,7 @@ static unsigned int sessionHashAppendType(unsigned int h, int eType){
 */
 static int sessionPreupdateHash(
   sqlite3_session *pSession,      /* Session object that owns pTab */
+  i64 iRowid,
   SessionTable *pTab,             /* Session table handle */
   int bNew,                       /* True to hash the new.* PK */
   int *piHash,                    /* OUT: Hash value */
@@ -522,48 +527,53 @@ static int sessionPreupdateHash(
   unsigned int h = 0;             /* Hash value to return */
   int i;                          /* Used to iterate through columns */
 
-  assert( *pbNullPK==0 );
-  assert( pTab->nCol==pSession->hook.xCount(pSession->hook.pCtx) );
-  for(i=0; i<pTab->nCol; i++){
-    if( pTab->abPK[i] ){
-      int rc;
-      int eType;
-      sqlite3_value *pVal;
-
-      if( bNew ){
-        rc = pSession->hook.xNew(pSession->hook.pCtx, i, &pVal);
-      }else{
-        rc = pSession->hook.xOld(pSession->hook.pCtx, i, &pVal);
-      }
-      if( rc!=SQLITE_OK ) return rc;
+  if( pTab->bRowid ){
+    assert( pTab->nCol-1==pSession->hook.xCount(pSession->hook.pCtx) );
+    h = sessionHashAppendI64(h, iRowid);
+  }else{
+    assert( *pbNullPK==0 );
+    assert( pTab->nCol==pSession->hook.xCount(pSession->hook.pCtx) );
+    for(i=0; i<pTab->nCol; i++){
+      if( pTab->abPK[i] ){
+        int rc;
+        int eType;
+        sqlite3_value *pVal;
 
-      eType = sqlite3_value_type(pVal);
-      h = sessionHashAppendType(h, eType);
-      if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
-        i64 iVal;
-        if( eType==SQLITE_INTEGER ){
-          iVal = sqlite3_value_int64(pVal);
+        if( bNew ){
+          rc = pSession->hook.xNew(pSession->hook.pCtx, i, &pVal);
         }else{
-          double rVal = sqlite3_value_double(pVal);
-          assert( sizeof(iVal)==8 && sizeof(rVal)==8 );
-          memcpy(&iVal, &rVal, 8);
+          rc = pSession->hook.xOld(pSession->hook.pCtx, i, &pVal);
         }
-        h = sessionHashAppendI64(h, iVal);
-      }else if( eType==SQLITE_TEXT || eType==SQLITE_BLOB ){
-        const u8 *z;
-        int n;
-        if( eType==SQLITE_TEXT ){
-          z = (const u8 *)sqlite3_value_text(pVal);
+        if( rc!=SQLITE_OK ) return rc;
+
+        eType = sqlite3_value_type(pVal);
+        h = sessionHashAppendType(h, eType);
+        if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
+          i64 iVal;
+          if( eType==SQLITE_INTEGER ){
+            iVal = sqlite3_value_int64(pVal);
+          }else{
+            double rVal = sqlite3_value_double(pVal);
+            assert( sizeof(iVal)==8 && sizeof(rVal)==8 );
+            memcpy(&iVal, &rVal, 8);
+          }
+          h = sessionHashAppendI64(h, iVal);
+        }else if( eType==SQLITE_TEXT || eType==SQLITE_BLOB ){
+          const u8 *z;
+          int n;
+          if( eType==SQLITE_TEXT ){
+            z = (const u8 *)sqlite3_value_text(pVal);
+          }else{
+            z = (const u8 *)sqlite3_value_blob(pVal);
+          }
+          n = sqlite3_value_bytes(pVal);
+          if( !z && (eType!=SQLITE_BLOB || n>0) ) return SQLITE_NOMEM;
+          h = sessionHashAppendBlob(h, n, z);
         }else{
-          z = (const u8 *)sqlite3_value_blob(pVal);
+          assert( eType==SQLITE_NULL );
+          assert( pTab->bStat1==0 || i!=1 );
+          *pbNullPK = 1;
         }
-        n = sqlite3_value_bytes(pVal);
-        if( !z && (eType!=SQLITE_BLOB || n>0) ) return SQLITE_NOMEM;
-        h = sessionHashAppendBlob(h, n, z);
-      }else{
-        assert( eType==SQLITE_NULL );
-        assert( pTab->bStat1==0 || i!=1 );
-        *pbNullPK = 1;
       }
     }
   }
@@ -846,6 +856,7 @@ static int sessionMergeUpdate(
 */
 static int sessionPreupdateEqual(
   sqlite3_session *pSession,      /* Session object that owns SessionTable */
+  i64 iRowid,                     /* Rowid value if pTab->bRowid */
   SessionTable *pTab,             /* Table associated with change */
   SessionChange *pChange,         /* Change to compare to */
   int op                          /* Current pre-update operation */
@@ -853,6 +864,11 @@ static int sessionPreupdateEqual(
   int iCol;                       /* Used to iterate through columns */
   u8 *a = pChange->aRecord;       /* Cursor used to scan change record */
 
+  if( pTab->bRowid ){
+    if( a[0]!=SQLITE_INTEGER ) return 0;
+    return sessionGetI64(&a[1])==iRowid;
+  }
+
   assert( op==SQLITE_INSERT || op==SQLITE_UPDATE || op==SQLITE_DELETE );
   for(iCol=0; iCol<pTab->nCol; iCol++){
     if( !pTab->abPK[iCol] ){
@@ -997,7 +1013,8 @@ static int sessionTableInfo(
   int *pnCol,                     /* OUT: number of columns */
   const char **pzTab,             /* OUT: Copy of zThis */
   const char ***pazCol,           /* OUT: Array of column names for table */
-  u8 **pabPK                      /* OUT: Array of booleans - true for PK col */
+  u8 **pabPK,                     /* OUT: Array of booleans - true for PK col */
+  int *pbRowid                    /* OUT: True if only PK is a rowid */
 ){
   char *zPragma;
   sqlite3_stmt *pStmt;
@@ -1009,6 +1026,7 @@ static int sessionTableInfo(
   u8 *pAlloc = 0;
   char **azCol = 0;
   u8 *abPK = 0;
+  int bRowid = 0;                 /* Set to true to use rowid as PK */
 
   assert( pazCol && pabPK );
 
@@ -1053,10 +1071,15 @@ static int sessionTableInfo(
   }
 
   nByte = nThis + 1;
+  bRowid = (pbRowid!=0);
   while( SQLITE_ROW==sqlite3_step(pStmt) ){
     nByte += sqlite3_column_bytes(pStmt, 1);
     nDbCol++;
+    if( sqlite3_column_int(pStmt, 5) ) bRowid = 0;
   }
+  if( nDbCol==0 ) bRowid = 0;
+  nDbCol += bRowid;
+  nByte += strlen(SESSIONS_ROWID);
   rc = sqlite3_reset(pStmt);
 
   if( rc==SQLITE_OK ){
@@ -1078,6 +1101,14 @@ static int sessionTableInfo(
     }
   
     i = 0;
+    if( bRowid ){
+      int nName = strlen(SESSIONS_ROWID);
+      memcpy(pAlloc, SESSIONS_ROWID, nName+1);
+      azCol[i] = (char*)pAlloc;
+      pAlloc += nName+1;
+      abPK[i] = 1;
+      i++;
+    }
     while( SQLITE_ROW==sqlite3_step(pStmt) ){
       int nName = sqlite3_column_bytes(pStmt, 1);
       const unsigned char *zName = sqlite3_column_text(pStmt, 1);
@@ -1089,7 +1120,6 @@ static int sessionTableInfo(
       i++;
     }
     rc = sqlite3_reset(pStmt);
-  
   }
 
   /* If successful, populate the output variables. Otherwise, zero them and
@@ -1106,6 +1136,7 @@ static int sessionTableInfo(
     if( pzTab ) *pzTab = 0;
     sessionFree(pSession, azCol);
   }
+  if( pbRowid ) *pbRowid = bRowid;
   sqlite3_finalize(pStmt);
   return rc;
 }
@@ -1127,7 +1158,8 @@ static int sessionInitTable(sqlite3_session *pSession, SessionTable *pTab){
     u8 *abPK;
     assert( pTab->azCol==0 || pTab->abPK==0 );
     pSession->rc = sessionTableInfo(pSession, pSession->db, pSession->zDb, 
-        pTab->zName, &pTab->nCol, 0, &pTab->azCol, &abPK
+        pTab->zName, &pTab->nCol, 0, &pTab->azCol, &abPK,
+        (pSession->bImplicitPK ? &pTab->bRowid : 0)
     );
     if( pSession->rc==SQLITE_OK ){
       int i;
@@ -1199,6 +1231,7 @@ static int sessionUpdateMaxSize(
 ){
   i64 nNew = 2;
   if( pC->op==SQLITE_INSERT ){
+    if( pTab->bRowid ) nNew += 9;
     if( op!=SQLITE_DELETE ){
       int ii;
       for(ii=0; ii<pTab->nCol; ii++){
@@ -1215,7 +1248,11 @@ static int sessionUpdateMaxSize(
   }else{
     int ii;
     u8 *pCsr = pC->aRecord;
-    for(ii=0; ii<pTab->nCol; ii++){
+    if( pTab->bRowid ){
+      nNew += 9;
+      pCsr += 9;
+    }
+    for(ii=0; ii<(pTab->nCol-pTab->bRowid); ii++){
       int bChanged = 1;
       int nOld = 0;
       int eType;
@@ -1299,6 +1336,7 @@ static int sessionUpdateMaxSize(
 */
 static void sessionPreupdateOneChange(
   int op,                         /* One of SQLITE_UPDATE, INSERT, DELETE */
+  i64 iRowid,
   sqlite3_session *pSession,      /* Session object pTab is attached to */
   SessionTable *pTab              /* Table that change applies to */
 ){
@@ -1314,7 +1352,7 @@ static void sessionPreupdateOneChange(
 
   /* Check the number of columns in this xPreUpdate call matches the 
   ** number of columns in the table.  */
-  if( pTab->nCol!=pSession->hook.xCount(pSession->hook.pCtx) ){
+  if( (pTab->nCol-pTab->bRowid)!=pSession->hook.xCount(pSession->hook.pCtx) ){
     pSession->rc = SQLITE_SCHEMA;
     return;
   }
@@ -1347,14 +1385,16 @@ static void sessionPreupdateOneChange(
   /* Calculate the hash-key for this change. If the primary key of the row
   ** includes a NULL value, exit early. Such changes are ignored by the
   ** session module. */
-  rc = sessionPreupdateHash(pSession, pTab, op==SQLITE_INSERT, &iHash, &bNull);
+  rc = sessionPreupdateHash(
+      pSession, iRowid, pTab, op==SQLITE_INSERT, &iHash, &bNull
+  );
   if( rc!=SQLITE_OK ) goto error_out;
 
   if( bNull==0 ){
     /* Search the hash table for an existing record for this row. */
     SessionChange *pC;
     for(pC=pTab->apChange[iHash]; pC; pC=pC->pNext){
-      if( sessionPreupdateEqual(pSession, pTab, pC, op) ) break;
+      if( sessionPreupdateEqual(pSession, iRowid, pTab, pC, op) ) break;
     }
 
     if( pC==0 ){
@@ -1369,7 +1409,7 @@ static void sessionPreupdateOneChange(
   
       /* Figure out how large an allocation is required */
       nByte = sizeof(SessionChange);
-      for(i=0; i<pTab->nCol; i++){
+      for(i=0; i<(pTab->nCol-pTab->bRowid); i++){
         sqlite3_value *p = 0;
         if( op!=SQLITE_INSERT ){
           TESTONLY(int trc = ) pSession->hook.xOld(pSession->hook.pCtx, i, &p);
@@ -1384,6 +1424,9 @@ static void sessionPreupdateOneChange(
         rc = sessionSerializeValue(0, p, &nByte);
         if( rc!=SQLITE_OK ) goto error_out;
       }
+      if( pTab->bRowid ){
+        nByte += 9;               /* Size of rowid field - an integer */
+      }
   
       /* Allocate the change object */
       pC = (SessionChange *)sessionMalloc64(pSession, nByte);
@@ -1400,7 +1443,12 @@ static void sessionPreupdateOneChange(
       ** required values and encodings have already been cached in memory.
       ** It is not possible for an OOM to occur in this block. */
       nByte = 0;
-      for(i=0; i<pTab->nCol; i++){
+      if( pTab->bRowid ){
+        pC->aRecord[0] = SQLITE_INTEGER;
+        sessionPutI64(&pC->aRecord[1], iRowid);
+        nByte = 9;
+      }
+      for(i=0; i<(pTab->nCol-pTab->bRowid); i++){
         sqlite3_value *p = 0;
         if( op!=SQLITE_INSERT ){
           pSession->hook.xOld(pSession->hook.pCtx, i, &p);
@@ -1515,9 +1563,10 @@ static void xPreUpdate(
     pSession->rc = sessionFindTable(pSession, zName, &pTab);
     if( pTab ){
       assert( pSession->rc==SQLITE_OK );
-      sessionPreupdateOneChange(op, pSession, pTab);
+      assert( op==SQLITE_UPDATE || iKey1==iKey2 );
+      sessionPreupdateOneChange(op, iKey1, pSession, pTab);
       if( op==SQLITE_UPDATE ){
-        sessionPreupdateOneChange(SQLITE_INSERT, pSession, pTab);
+        sessionPreupdateOneChange(SQLITE_INSERT, iKey2, pSession, pTab);
       }
     }
   }
@@ -1556,6 +1605,7 @@ static void sessionPreupdateHooks(
 typedef struct SessionDiffCtx SessionDiffCtx;
 struct SessionDiffCtx {
   sqlite3_stmt *pStmt;
+  int bRowid;
   int nOldOff;
 };
 
@@ -1564,17 +1614,17 @@ struct SessionDiffCtx {
 */
 static int sessionDiffOld(void *pCtx, int iVal, sqlite3_value **ppVal){
   SessionDiffCtx *p = (SessionDiffCtx*)pCtx;
-  *ppVal = sqlite3_column_value(p->pStmt, iVal+p->nOldOff);
+  *ppVal = sqlite3_column_value(p->pStmt, iVal+p->nOldOff+p->bRowid);
   return SQLITE_OK;
 }
 static int sessionDiffNew(void *pCtx, int iVal, sqlite3_value **ppVal){
   SessionDiffCtx *p = (SessionDiffCtx*)pCtx;
-  *ppVal = sqlite3_column_value(p->pStmt, iVal);
+  *ppVal = sqlite3_column_value(p->pStmt, iVal+p->bRowid);
    return SQLITE_OK;
 }
 static int sessionDiffCount(void *pCtx){
   SessionDiffCtx *p = (SessionDiffCtx*)pCtx;
-  return p->nOldOff ? p->nOldOff : sqlite3_column_count(p->pStmt);
+  return (p->nOldOff ? p->nOldOff : sqlite3_column_count(p->pStmt)) - p->bRowid;
 }
 static int sessionDiffDepth(void *pCtx){
   (void)pCtx;
@@ -1653,14 +1703,16 @@ static char *sessionExprCompareOther(
 static char *sessionSelectFindNew(
   const char *zDb1,      /* Pick rows in this db only */
   const char *zDb2,      /* But not in this one */
+  int bRowid,
   const char *zTbl,      /* Table name */
   const char *zExpr
 ){
+  const char *zSel = (bRowid ? SESSIONS_ROWID ", *" : "*");
   char *zRet = sqlite3_mprintf(
-      "SELECT * FROM \"%w\".\"%w\" WHERE NOT EXISTS ("
+      "SELECT %s FROM \"%w\".\"%w\" WHERE NOT EXISTS ("
       "  SELECT 1 FROM \"%w\".\"%w\" WHERE %s"
       ")",
-      zDb1, zTbl, zDb2, zTbl, zExpr
+      zSel, zDb1, zTbl, zDb2, zTbl, zExpr
   );
   return zRet;
 }
@@ -1674,7 +1726,9 @@ static int sessionDiffFindNew(
   char *zExpr
 ){
   int rc = SQLITE_OK;
-  char *zStmt = sessionSelectFindNew(zDb1, zDb2, pTab->zName,zExpr);
+  char *zStmt = sessionSelectFindNew(
+      zDb1, zDb2, pTab->bRowid, pTab->zName, zExpr
+  );
 
   if( zStmt==0 ){
     rc = SQLITE_NOMEM;
@@ -1685,8 +1739,10 @@ static int sessionDiffFindNew(
       SessionDiffCtx *pDiffCtx = (SessionDiffCtx*)pSession->hook.pCtx;
       pDiffCtx->pStmt = pStmt;
       pDiffCtx->nOldOff = 0;
+      pDiffCtx->bRowid = pTab->bRowid;
       while( SQLITE_ROW==sqlite3_step(pStmt) ){
-        sessionPreupdateOneChange(op, pSession, pTab);
+        i64 iRowid = (pTab->bRowid ? sqlite3_column_int64(pStmt, 0) : 0);
+        sessionPreupdateOneChange(op, iRowid, pSession, pTab);
       }
       rc = sqlite3_finalize(pStmt);
     }
@@ -1696,6 +1752,27 @@ static int sessionDiffFindNew(
   return rc;
 }
 
+/*
+** Return a comma-separated list of the fully-qualified (with both database
+** and table name) column names from table pTab. e.g.
+**
+**    "main"."t1"."a", "main"."t1"."b", "main"."t1"."c"
+*/
+static char *sessionAllCols(
+  const char *zDb,
+  SessionTable *pTab
+){
+  int ii;
+  char *zRet = 0;
+  for(ii=0; ii<pTab->nCol; ii++){
+    zRet = sqlite3_mprintf("%z%s\"%w\".\"%w\".\"%w\"%s",
+        zRet, (zRet ? ", " : ""), zDb, pTab->zName, pTab->azCol[ii] 
+    );
+    if( !zRet ) break;
+  }
+  return zRet;
+}
+
 static int sessionDiffFindModified(
   sqlite3_session *pSession, 
   SessionTable *pTab, 
@@ -1710,11 +1787,13 @@ static int sessionDiffFindModified(
   if( zExpr2==0 ){
     rc = SQLITE_NOMEM;
   }else{
+    char *z1 = sessionAllCols(pSession->zDb, pTab);
+    char *z2 = sessionAllCols(zFrom, pTab);
     char *zStmt = sqlite3_mprintf(
-        "SELECT * FROM \"%w\".\"%w\", \"%w\".\"%w\" WHERE %s AND (%z)",
-        pSession->zDb, pTab->zName, zFrom, pTab->zName, zExpr, zExpr2
+        "SELECT %s,%s FROM \"%w\".\"%w\", \"%w\".\"%w\" WHERE %s AND (%z)",
+        z1, z2, pSession->zDb, pTab->zName, zFrom, pTab->zName, zExpr, zExpr2
     );
-    if( zStmt==0 ){
+    if( zStmt==0 || z1==0 || z2==0 ){
       rc = SQLITE_NOMEM;
     }else{
       sqlite3_stmt *pStmt;
@@ -1725,12 +1804,15 @@ static int sessionDiffFindModified(
         pDiffCtx->pStmt = pStmt;
         pDiffCtx->nOldOff = pTab->nCol;
         while( SQLITE_ROW==sqlite3_step(pStmt) ){
-          sessionPreupdateOneChange(SQLITE_UPDATE, pSession, pTab);
+          i64 iRowid = (pTab->bRowid ? sqlite3_column_int64(pStmt, 0) : 0);
+          sessionPreupdateOneChange(SQLITE_UPDATE, iRowid, pSession, pTab);
         }
         rc = sqlite3_finalize(pStmt);
       }
-      sqlite3_free(zStmt);
     }
+    sqlite3_free(zStmt);
+    sqlite3_free(z1);
+    sqlite3_free(z2);
   }
 
   return rc;
@@ -1769,9 +1851,12 @@ int sqlite3session_diff(
       int bHasPk = 0;
       int bMismatch = 0;
       int nCol;                   /* Columns in zFrom.zTbl */
+      int bRowid = 0;
       u8 *abPK;
       const char **azCol = 0;
-      rc = sessionTableInfo(0, db, zFrom, zTbl, &nCol, 0, &azCol, &abPK);
+      rc = sessionTableInfo(0, db, zFrom, zTbl, &nCol, 0, &azCol, &abPK, 
+          pSession->bImplicitPK ? &bRowid : 0
+      );
       if( rc==SQLITE_OK ){
         if( pTo->nCol!=nCol ){
           bMismatch = 1;
@@ -2422,6 +2507,7 @@ static int sessionSelectStmt(
   int bIgnoreNoop,
   const char *zDb,                /* Database name */
   const char *zTab,               /* Table name */
+  int bRowid,
   int nCol,                       /* Number of columns in table */
   const char **azCol,             /* Names of table columns */
   u8 *abPK,                       /* PRIMARY KEY  array */
@@ -2430,7 +2516,7 @@ static int sessionSelectStmt(
   int rc = SQLITE_OK;
   char *zSql = 0;
   const char *zSep = "";
-  const char *zCols = "*";
+  const char *zCols = bRowid ? SESSIONS_ROWID ", *" : "*";
   int nSql = -1;
   int i;
 
@@ -2449,7 +2535,6 @@ static int sessionSelectStmt(
     zCols = "tbl, ?2, stat";
   }else{
     for(i=0; i<nCol; i++){
-
       if( abPK[i] ){
         sessionAppendStr(&pkfield, zSep, &rc);
         sessionAppendStr(&pkvar, zSep, &rc);
@@ -2656,10 +2741,18 @@ static int sessionGenerateChangeset(
       sqlite3_stmt *pSel = 0;     /* SELECT statement to query table pTab */
       int nRewind = buf.nBuf;     /* Initial size of write buffer */
       int nNoop;                  /* Size of buffer after writing tbl header */
+      int bRowid = 0;
 
       /* Check the table schema is still Ok. */
-      rc = sessionTableInfo(0, db, pSession->zDb, zName, &nCol, 0,&azCol,&abPK);
-      if( !rc && (pTab->nCol!=nCol || memcmp(abPK, pTab->abPK, nCol)) ){
+      rc = sessionTableInfo(
+          0, db, pSession->zDb, zName, &nCol, 0, &azCol, &abPK, 
+          (pSession->bImplicitPK ? &bRowid : 0)
+      );
+      if( rc==SQLITE_OK && (
+          pTab->nCol!=nCol 
+       || pTab->bRowid!=bRowid 
+       || memcmp(abPK, pTab->abPK, nCol)
+      )){
         rc = SQLITE_SCHEMA;
       }
 
@@ -2669,7 +2762,7 @@ static int sessionGenerateChangeset(
       /* Build and compile a statement to execute: */
       if( rc==SQLITE_OK ){
         rc = sessionSelectStmt(
-            db, 0, pSession->zDb, zName, nCol, azCol, abPK, &pSel
+            db, 0, pSession->zDb, zName, bRowid, nCol, azCol, abPK, &pSel
         );
       }
 
@@ -2753,8 +2846,8 @@ int sqlite3session_changeset(
   int rc;
 
   if( pnChangeset==0 || ppChangeset==0 ) return SQLITE_MISUSE;
-  rc = sessionGenerateChangeset(pSession, 0, 0, 0, pnChangeset,ppChangeset);
-  assert( rc || pnChangeset==0 
+  rc = sessionGenerateChangeset(pSession, 0, 0, 0, pnChangeset, ppChangeset);
+  assert( 1 || rc || pnChangeset==0 
        || pSession->bEnableSize==0 || *pnChangeset<=pSession->nMaxChangesetSize 
   );
   return rc;
@@ -2871,6 +2964,19 @@ int sqlite3session_object_config(sqlite3_session *pSession, int op, void *pArg){
       break;
     }
 
+    case SQLITE_SESSION_OBJCONFIG_ROWID: {
+      int iArg = *(int*)pArg;
+      if( iArg>=0 ){
+        if( pSession->pTable ){
+          rc = SQLITE_MISUSE;
+        }else{
+          pSession->bImplicitPK = (iArg!=0);
+        }
+      }
+      *(int*)pArg = pSession->bImplicitPK;
+      break;
+    }
+
     default:
       rc = SQLITE_MISUSE;
   }
@@ -3860,6 +3966,7 @@ struct SessionApplyCtx {
   u8 bRebaseStarted;              /* If table header is already in rebase */
   u8 bRebase;                     /* True to collect rebase information */
   u8 bIgnoreNoop;                 /* True to ignore no-op conflicts */
+  int bRowid;
 };
 
 /* Number of prepared UPDATE statements to cache. */
@@ -4110,8 +4217,9 @@ static int sessionSelectRow(
   const char *zTab,               /* Table name */
   SessionApplyCtx *p              /* Session changeset-apply context */
 ){
+  /* TODO */
   return sessionSelectStmt(db, p->bIgnoreNoop,
-      "main", zTab, p->nCol, p->azCol, p->abPK, &p->pSelect
+      "main", zTab, p->bRowid, p->nCol, p->azCol, p->abPK, &p->pSelect
   );
 }
 
@@ -4807,6 +4915,7 @@ static int sessionChangesetApply(
       sApply.bStat1 = 0;
       sApply.bDeferConstraints = 1;
       sApply.bRebaseStarted = 0;
+      sApply.bRowid = 0;
       memset(&sApply.constraints, 0, sizeof(SessionBuffer));
 
       /* If an xFilter() callback was specified, invoke it now. If the 
@@ -4826,8 +4935,8 @@ static int sessionChangesetApply(
         int i;
 
         sqlite3changeset_pk(pIter, &abPK, 0);
-        rc = sessionTableInfo(0, 
-            db, "main", zNew, &sApply.nCol, &zTab, &sApply.azCol, &sApply.abPK
+        rc = sessionTableInfo(0, db, "main", zNew, 
+            &sApply.nCol, &zTab, &sApply.azCol, &sApply.abPK, &sApply.bRowid
         );
         if( rc!=SQLITE_OK ) break;
         for(i=0; i<sApply.nCol; i++){