SQLite

Check-in [2305411097]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Experimental sqlite_db_config() setting to disable writing to all btrees except for one btree with a particular root page.
Downloads: Tarball | ZIP archive
Timelines: family | ancestors | descendants | both | one-writable-btree
Files: files | file ages | folders
SHA1: 2305411097c4985b61c5faf4361c4da8414101f2
User & Date: drh 2015-01-29 02:26:40.456
Context
2015-01-29
14:48
Avoid overlength command lines in Makefile.msc when using TOP= with a large directory name. (check-in: 0cdd59bf36 user: drh tags: one-writable-btree)
02:26
Experimental sqlite_db_config() setting to disable writing to all btrees except for one btree with a particular root page. (check-in: 2305411097 user: drh tags: one-writable-btree)
2015-01-27
21:24
Fix harmless compiler warnings. (check-in: e7d2ec048c user: mistachkin tags: trunk)
Changes
Side-by-Side Diff Ignore Whitespace Patch
Changes to src/delete.c.
670
671
672
673
674
675
676

677
678
679




680
681
682
683
684
685
686
670
671
672
673
674
675
676
677



678
679
680
681
682
683
684
685
686
687
688







+
-
-
-
+
+
+
+







  }

  /* Delete the index and table entries. Skip this step if pTab is really
  ** a view (in which case the only effect of the DELETE statement is to
  ** fire the INSTEAD OF triggers).  */ 
  if( pTab->pSelect==0 ){
    sqlite3GenerateRowIndexDelete(pParse, pTab, iDataCur, iIdxCur, 0);
    if( !WRITE_RESTRICT(pParse->db, pTab->tnum) ){
    sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, (count?OPFLAG_NCHANGE:0));
    if( count ){
      sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT);
      sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, (count?OPFLAG_NCHANGE:0));
      if( count ){
        sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT);
      }
    }
  }

  /* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
  ** handle rows (possibly in other tables) that refer via a foreign key
  ** to the row just deleted. */ 
  sqlite3FkActions(pParse, pTab, 0, iOld, 0, 0);
732
733
734
735
736
737
738

739
740
741
742
743
744
745
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748







+








  v = pParse->pVdbe;
  pPk = HasRowid(pTab) ? 0 : sqlite3PrimaryKeyIndex(pTab);
  for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
    assert( iIdxCur+i!=iDataCur || pPk==pIdx );
    if( aRegIdx!=0 && aRegIdx[i]==0 ) continue;
    if( pIdx==pPk ) continue;
    if( WRITE_RESTRICT(pParse->db, pIdx->tnum) ) continue;
    VdbeModuleComment((v, "GenRowIdxDel for %s", pIdx->zName));
    r1 = sqlite3GenerateIndexKey(pParse, pIdx, iDataCur, 0, 1,
                                 &iPartIdxLabel, pPrior, r1);
    sqlite3VdbeAddOp3(v, OP_IdxDelete, iIdxCur+i, r1,
                      pIdx->uniqNotNull ? pIdx->nKeyCol : pIdx->nColumn);
    sqlite3ResolvePartIdxLabel(pParse, iPartIdxLabel);
    pPrior = pIdx;
Changes to src/insert.c.
1362
1363
1364
1365
1366
1367
1368

1369
1370
1371
1372
1373
1374
1375
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376







+







  for(ix=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, ix++){
    int regIdx;          /* Range of registers hold conent for pIdx */
    int regR;            /* Range of registers holding conflicting PK */
    int iThisCur;        /* Cursor for this UNIQUE index */
    int addrUniqueOk;    /* Jump here if the UNIQUE constraint is satisfied */

    if( aRegIdx[ix]==0 ) continue;  /* Skip indices that do not change */
    if( WRITE_RESTRICT(db, pIdx->tnum) ) continue;
    if( bAffinityDone==0 ){
      sqlite3TableAffinity(v, pTab, regNewData+1);
      bAffinityDone = 1;
    }
    iThisCur = iIdxCur+ix;
    addrUniqueOk = sqlite3VdbeMakeLabel(v);

1541
1542
1543
1544
1545
1546
1547

1548
1549
1550
1551
1552
1553
1554
1555
1556

1557
1558

1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573

1574
1575
1576
1577
1578
1579
1580
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585







+









+


+















+







  int *aRegIdx,       /* Register used by each index.  0 for unused indices */
  int isUpdate,       /* True for UPDATE, False for INSERT */
  int appendBias,     /* True if this is likely to be an append */
  int useSeekResult   /* True to set the USESEEKRESULT flag on OP_[Idx]Insert */
){
  Vdbe *v;            /* Prepared statements under construction */
  Index *pIdx;        /* An index being inserted or updated */
  sqlite3 *db;
  u8 pik_flags;       /* flag values passed to the btree insert */
  int regData;        /* Content registers (after the rowid) */
  int regRec;         /* Register holding assembled record for the table */
  int i;              /* Loop counter */
  u8 bAffinityDone = 0; /* True if OP_Affinity has been run already */

  v = sqlite3GetVdbe(pParse);
  assert( v!=0 );
  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
  db = pParse->db;
  for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
    if( aRegIdx[i]==0 ) continue;
    if( WRITE_RESTRICT(db, pIdx->tnum) ) continue;
    bAffinityDone = 1;
    if( pIdx->pPartIdxWhere ){
      sqlite3VdbeAddOp2(v, OP_IsNull, aRegIdx[i], sqlite3VdbeCurrentAddr(v)+2);
      VdbeCoverage(v);
    }
    sqlite3VdbeAddOp2(v, OP_IdxInsert, iIdxCur+i, aRegIdx[i]);
    pik_flags = 0;
    if( useSeekResult ) pik_flags = OPFLAG_USESEEKRESULT;
    if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) ){
      assert( pParse->nested==0 );
      pik_flags |= OPFLAG_NCHANGE;
    }
    if( pik_flags )  sqlite3VdbeChangeP5(v, pik_flags);
  }
  if( !HasRowid(pTab) ) return;
  if( WRITE_RESTRICT(db, pTab->tnum) ) return;
  regData = regNewData + 1;
  regRec = sqlite3GetTempReg(pParse);
  sqlite3VdbeAddOp3(v, OP_MakeRecord, regData, pTab->nCol, regRec);
  if( !bAffinityDone ) sqlite3TableAffinity(v, pTab, 0);
  sqlite3ExprCacheAffinityChange(pParse, regData, pTab->nCol);
  if( pParse->nested ){
    pik_flags = 0;
Changes to src/main.c.
720
721
722
723
724
725
726





727
728
729
730
731
732
733
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738







+
+
+
+
+







  switch( op ){
    case SQLITE_DBCONFIG_LOOKASIDE: {
      void *pBuf = va_arg(ap, void*); /* IMP: R-26835-10964 */
      int sz = va_arg(ap, int);       /* IMP: R-47871-25994 */
      int cnt = va_arg(ap, int);      /* IMP: R-04460-53386 */
      rc = setupLookaside(db, pBuf, sz, cnt);
      break;
    }
    case SQLITE_DBCONFIG_WRITABLE_BTREE: {
      db->onlyWritableBtree = va_arg(ap,int);
      rc = SQLITE_OK;
      break;
    }
    default: {
      static const struct {
        int op;      /* The opcode */
        u32 mask;    /* Mask of the bit in sqlite3.flags to set/clear */
      } aFlagOp[] = {
        { SQLITE_DBCONFIG_ENABLE_FKEY,    SQLITE_ForeignKeys    },
Changes to src/shell.c.
2563
2564
2565
2566
2567
2568
2569














































2570
2571
2572
2573
2574
2575
2576
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622







+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+







    sqlite3_exec(p->db, "PRAGMA database_list; ", callback, &data, &zErrMsg);
    if( zErrMsg ){
      fprintf(stderr,"Error: %s\n", zErrMsg);
      sqlite3_free(zErrMsg);
      rc = 1;
    }
  }else

  if( c=='d' && n>1 && strncmp(azArg[0], "dbconfig", n)==0 ){
    int nHit = 0, x;
    open_db(p, 0);
    if( nArg>=2 ){
      n = (int)strlen(azArg[1]);
      if( strncmp(azArg[1], "writable_btree",n)==0 ){
        if( nArg!=3 ){
          fprintf(stderr, "Usage: .dbconfig writable_btree N\n");
          rc = 1;
        }else{
          sqlite3_db_config(p->db, SQLITE_DBCONFIG_WRITABLE_BTREE,
                            integerValue(azArg[2]));
        }
        nHit = 1;
      }else
      if( strncmp(azArg[1], "enable_fkey",n)==0 ){
        if( nArg!=3 ){
          fprintf(stderr, "Usage: .dbconfig enable_fkey (1|0|-1)\n");
          rc = 1;
        }else{
          sqlite3_db_config(p->db, SQLITE_DBCONFIG_ENABLE_FKEY,
                            integerValue(azArg[2]), &x);
          printf("result: %d\n", x);
        }
        nHit = 1;
      }else
      if( strncmp(azArg[1], "enable_trigger",n)==0 ){
        if( nArg!=3 ){
          fprintf(stderr, "Usage: .dbconfig enable_trigger (1|0|-1)\n");
          rc = 1;
        }else{
          sqlite3_db_config(p->db, SQLITE_DBCONFIG_ENABLE_TRIGGER,
                            integerValue(azArg[2]), &x);
          printf("result: %d\n", x);
        }
        nHit = 1;
      }
    }
    if( nHit==0 ){
      fprintf(stderr, "Usage: .dbconfig COMMAND ARGS...\n");
      fprintf(stderr, 
        "COMMAND is one of: writable_btree enable_fkey enable_trigger\n");
      rc = 1;
    }    
  }else

  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 ){
Changes to src/sqlite.h.in.
1836
1837
1838
1839
1840
1841
1842








1843
1844
1845
1846
1847

1848
1849
1850
1851
1852
1853
1854
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863







+
+
+
+
+
+
+
+





+







** The first argument is an integer which is 0 to disable triggers,
** positive to enable triggers or negative to leave the setting unchanged.
** The second parameter is a pointer to an integer into which
** is written 0 or 1 to indicate whether triggers are disabled or enabled
** following this call.  The second parameter may be a NULL pointer, in
** which case the trigger setting is not reported back. </dd>
**
** <dt>SQLITE_DBCONFIG_WRITABLE_BTREE</dt>
** <dd> ^This option is used to disable INSERT and DELETE operations
** against all attached b-trees, except for b-trees that have a 
** particular root page. 
** There must be one additional integer argument which is the root page
** that is allowed to be written.  If the argument is zero, then
** writing is allowed to all b-trees, as is normally the case.
**
** </dl>
*/
#define SQLITE_DBCONFIG_LOOKASIDE       1001  /* void* int int */
#define SQLITE_DBCONFIG_ENABLE_FKEY     1002  /* int int* */
#define SQLITE_DBCONFIG_ENABLE_TRIGGER  1003  /* int int* */
#define SQLITE_DBCONFIG_WRITABLE_BTREE  1004  /* int */


/*
** CAPI3REF: Enable Or Disable Extended Result Codes
**
** ^The sqlite3_extended_result_codes() routine enables or disables the
** [extended result codes] feature of SQLite. ^The extended result
Changes to src/sqliteInt.h.
1073
1074
1075
1076
1077
1078
1079

1080
1081
1082
1083
1084
1085
1086
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087







+







  u8 mallocFailed;              /* True if we have seen a malloc failure */
  u8 dfltLockMode;              /* Default locking-mode for attached dbs */
  signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
  u8 suppressErr;               /* Do not issue error messages if true */
  u8 vtabOnConflict;            /* Value to return for s3_vtab_on_conflict() */
  u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
  int nextPagesize;             /* Pagesize after VACUUM if >0 */
  int onlyWritableBtree;        /* Do not write to any other b-tree */
  u32 magic;                    /* Magic number for detect library misuse */
  int nChange;                  /* Value returned by sqlite3_changes() */
  int nTotalChange;             /* Value returned by sqlite3_total_changes() */
  int aLimit[SQLITE_N_LIMIT];   /* Limits */
  int nMaxSorterMmap;           /* Maximum size of regions mapped by sorter */
  struct sqlite3InitInfo {      /* Information used during initialization */
    int newTnum;                /* Rootpage of table being initialized */
1162
1163
1164
1165
1166
1167
1168







1169
1170
1171
1172
1173
1174
1175
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183







+
+
+
+
+
+
+







  sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
#endif
#ifdef SQLITE_USER_AUTHENTICATION
  sqlite3_userauth auth;        /* User authentication information */
#endif
};

/*
** This macro returns true if the only_writable_btree pragma is turned
** on and is set to a btree root node other than N.
*/
#define WRITE_RESTRICT(db,N) ((db)->onlyWritableBtree>0 && \
                              (db)->onlyWritableBtree!=(N))

/*
** A macro to discover the encoding of a database.
*/
#define SCHEMA_ENC(db) ((db)->aDb[0].pSchema->enc)
#define ENC(db)        ((db)->enc)

/*