SQLite

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle INSERT statements in SQLite.
**
** $Id: insert.c,v 1.225 2008/01/17 16:22:15 drh Exp $
*/
#include "sqliteInt.h"

/*
** Set P4 of the most recently inserted opcode to a column affinity
** string for index pIdx. A column affinity string has one character
** for each column in the table, according to the affinity of the column:

/*
** Generate code to do constraint checks prior to an INSERT or an UPDATE.
**
** The input is a range of consecutive registers as follows:
**
**    1.  The rowid of the row to be updated before the update.  This
**        value is omitted unless we are doing an UPDATE that involves a
**        change to the record number. (Or writing to a virtual table.)
**
**    2.  The rowid of the row after the update.
**
**    3.  The data in the first column of the entry after the update.
**
**    i.  Data from middle columns...
**
**    N.  The data in the last column of the entry after the update.
**
** The regRowid parameter is the index of the register containing (2).
**
** The old rowid shown as entry (1) above is omitted unless both isUpdate
** and rowidChng are 1.  isUpdate is true for UPDATEs and false for

** INSERTs and rowidChng is true if the record number is being changed.


**
** The code generated by this routine store new index entries into
** registers identified by aRegIdx[].  No index entry is created for
** indices where aRegIdx[i]==0.  The order of indices in aRegIdx[] is
** the same as the order of indices on the linked list of indices
** attached to the table.
**

** for the constraint is used.
**
** The calling routine must open a read/write cursor for pTab with
** cursor number "baseCur".  All indices of pTab must also have open
** read/write cursors with cursor number baseCur+i for the i-th cursor.
** Except, if there is no possibility of a REPLACE action then
** cursors do not need to be open for indices where aRegIdx[i]==0.
**
** If the isUpdate flag is true, it means that the "baseCur" cursor is
** initially pointing to an entry that is being updated.  The isUpdate
** flag causes extra code to be generated so that the "baseCur" cursor
** is still pointing at the same entry after the routine returns.
** Without the isUpdate flag, the "baseCur" cursor might be moved.
*/
void sqlite3GenerateConstraintChecks(
  Parse *pParse,      /* The parser context */
  Table *pTab,        /* the table into which we are inserting */
  int baseCur,        /* Index of a read/write cursor pointing at pTab */
  int regRowid,       /* Index of the range of input registers */
  int *aRegIdx,       /* Register used by each index.  0 for unused indices */
  int rowidChng,      /* True if the rowid will change */
  int isUpdate,       /* True for UPDATE, False for INSERT */
  int overrideError,  /* Override onError to this if not OE_Default */
  int ignoreDest      /* Jump to this label on an OE_Ignore resolution */
){
  int i;
  Vdbe *v;
  int nCol;
  int onError;
  int j1, j2, j3;     /* Address of jump instructions */
  int regData;        /* Register containing first data column */
  int iCur;
  Index *pIdx;
  int seenReplace = 0;
  int hasTwoRowids = (isUpdate && rowidChng);

  v = sqlite3GetVdbe(pParse);

    onError = pTab->keyConf;
    if( overrideError!=OE_Default ){
      onError = overrideError;
    }else if( onError==OE_Default ){
      onError = OE_Abort;
    }
    



    if( isUpdate ){
      j2 = sqlite3VdbeAddOp3(v, OP_Eq, regRowid, 0, regRowid-1);
    }
    j3 = sqlite3VdbeAddOp3(v, OP_NotExists, baseCur, 0, regRowid);
    switch( onError ){
      default: {
        onError = OE_Abort;
        /* Fall thru into the next case */
      }
      case OE_Rollback:
      case OE_Abort:
      case OE_Fail: {
        sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, onError, 0,
                         "PRIMARY KEY must be unique", P4_STATIC);
        break;
      }
      case OE_Replace: {
        sqlite3GenerateRowIndexDelete(pParse, pTab, baseCur, 0);
        if( isUpdate ){
          sqlite3VdbeAddOp3(v, OP_MoveGe, baseCur, 0, regRowid-hasTwoRowids);
        }
        seenReplace = 1;
        break;
      }
      case OE_Ignore: {
        assert( seenReplace==0 );
        sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
        break;
      }
    }
    sqlite3VdbeJumpHere(v, j3);
    if( isUpdate ){
      sqlite3VdbeJumpHere(v, j2);
      sqlite3VdbeAddOp3(v, OP_MoveGe, baseCur, 0, regRowid-1);

    }
  }

  /* Test all UNIQUE constraints by creating entries for each UNIQUE
  ** index and making sure that duplicate entries do not already exist.
  ** Add the new records to the indices as we go.
  */

      case OE_Ignore: {
        assert( seenReplace==0 );
        sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
        break;
      }
      case OE_Replace: {
        sqlite3GenerateRowDelete(pParse, pTab, baseCur, regR, 0);
        if( isUpdate ){
          sqlite3VdbeAddOp3(v, OP_MoveGe, baseCur, 0, regRowid-hasTwoRowids);
        }
        seenReplace = 1;
        break;
      }
    }
    sqlite3VdbeJumpHere(v, j2);
    sqlite3VdbeJumpHere(v, j3);
    sqlite3ReleaseTempReg(pParse, regR);

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.405 2008/01/17 17:15:56 drh Exp $
*/
#include "sqliteInt.h"


/*
** Delete all the content of a Select structure but do not deallocate
** the select structure itself.

    }

    /* Construct a record from the query result, but instead of
    ** saving that record, use it as a key to delete elements from
    ** the temporary table iParm.
    */
    case SRT_Except: {
      int addr, r1;
      r1 = sqlite3GetTempReg(pParse);
      addr = sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
      sqlite3VdbeChangeP4(v, -1, aff, P4_STATIC);
      sqlite3VdbeAddOp3(v, OP_NotFound, iParm, addr+3, r1);
      sqlite3VdbeAddOp1(v, OP_Delete, iParm);
      sqlite3ReleaseTempReg(pParse, r1);
      break;
    }
#endif

    /* Store the result as data using a unique key.
    */

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle UPDATE statements.
**
** $Id: update.c,v 1.169 2008/01/17 16:22:15 drh Exp $
*/
#include "sqliteInt.h"

#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Forward declaration */
static void updateVirtualTable(
  Parse *pParse,       /* The parsing context */

                         ** aXRef[i]==-1 if the i-th column is not changed. */
  int chngRowid;         /* True if the record number is being changed */
  Expr *pRowidExpr = 0;  /* Expression defining the new record number */
  int openAll = 0;       /* True if all indices need to be opened */
  AuthContext sContext;  /* The authorization context */
  NameContext sNC;       /* The name-context to resolve expressions in */
  int iDb;               /* Database containing the table being updated */


#ifndef SQLITE_OMIT_TRIGGER
  int isView;                  /* Trying to update a view */
  int triggers_exist = 0;      /* True if any row triggers exist */
#endif
  int iBeginAfterTrigger;      /* Address of after trigger program */
  int iEndAfterTrigger;        /* Exit of after trigger program */

    */
    sqlite3GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
                                    aRegIdx, chngRowid, 1,
                                    onError, addr);

    /* Delete the old indices for the current record.
    */

    sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);

    /* If changing the record number, delete the old record.
    */
    if( chngRowid ){
      sqlite3VdbeAddOp2(v, OP_Delete, iCur, 0);
    }


    /* Create the new index entries and the new record.
    */
    sqlite3CompleteInsertion(pParse, pTab, iCur, regNewRowid, 
                             aRegIdx, chngRowid, 1, -1, 0);
  }

**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.699 2008/01/18 14:08:25 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
#include "vdbeInt.h"

/*
** The following global variable is incremented every time a cursor

      if( db->nProgressOps==nProgressOps ){
        int prc;
        if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
        prc =db->xProgress(db->pProgressArg);
        if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
        if( prc!=0 ){
          rc = SQLITE_INTERRUPT;
          goto vdbe_halt;
        }
        nProgressOps = 0;
      }
      nProgressOps++;
    }
#endif

  assert( pOp->p2>0 );
  assert( pOp->p2<=p->nMem );
  pOut = &p->aMem[pOp->p2];
  assert( pOut!=pIn1 );
  if( pOp->opcode==OP_Move ){
    rc = sqlite3VdbeMemMove(pOut, pIn1);
  }else{
    Release(pOut);
    sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
    if( pOp->opcode==OP_Copy ){
      Deephemeralize(pOut);
    }
  }
  REGISTER_TRACE(pOp->p2, pOut);
  break;

case OP_Add:                   /* same as TK_PLUS, in1, in2, out3 */
case OP_Subtract:              /* same as TK_MINUS, in1, in2, out3 */
case OP_Multiply:              /* same as TK_STAR, in1, in2, out3 */
case OP_Divide:                /* same as TK_SLASH, in1, in2, out3 */
case OP_Remainder: {           /* same as TK_REM, in1, in2, out3 */
  int flags;
  flags = pIn1->flags | pIn2->flags;
  if( (flags & MEM_Null)!=0 ){
    Release(pOut);
    pOut->flags = MEM_Null;
  }else if( (pIn1->flags & pIn2->flags & MEM_Int)==MEM_Int ){
    i64 a, b;
    a = pIn1->u.i;
    b = pIn2->u.i;
    switch( pOp->opcode ){
      case OP_Add:         b += a;       break;
      case OP_Subtract:    b -= a;       break;
      case OP_Multiply:    b *= a;       break;
      case OP_Divide: {
        if( a==0 ) goto divide_by_zero;
        /* Dividing the largest possible negative 64-bit integer (1<<63) by 
        ** -1 returns an integer to large to store in a 64-bit data-type. On
        ** some architectures, the value overflows to (1<<63). On others,
        ** a SIGFPE is issued. The following statement normalizes this
        ** behaviour so that all architectures behave as if integer 
        ** overflow occured.
        */
        if( a==-1 && b==(((i64)1)<<63) ) a = 1;
        b /= a;
        break;
      }
      default: {
        if( a==0 ) goto divide_by_zero;
        if( a==-1 ) a = 1;
        b %= a;
        break;
      }
    }
    Release(pOut);
    pOut->u.i = b;
    pOut->flags = MEM_Int;
  }else{
    double a, b;
    a = sqlite3VdbeRealValue(pIn1);
    b = sqlite3VdbeRealValue(pIn2);
    switch( pOp->opcode ){
      case OP_Add:         b += a;       break;
      case OP_Subtract:    b -= a;       break;
      case OP_Multiply:    b *= a;       break;
      case OP_Divide: {
        if( a==0.0 ) goto divide_by_zero;
        b /= a;
        break;
      }
      default: {
        i64 ia = (i64)a;
        i64 ib = (i64)b;
        if( ia==0 ) goto divide_by_zero;
        if( ia==-1 ) ia = 1;
        b = ib % ia;
        break;
      }
    }
    if( sqlite3_isnan(b) ){
      goto divide_by_zero;
    }
    Release(pOut);
    pOut->r = b;
    pOut->flags = MEM_Real;
    if( (flags & MEM_Real)==0 ){
      sqlite3VdbeIntegerAffinity(pOut);
    }
  }
  break;

divide_by_zero:
  Release(pOut);
  pOut->flags = MEM_Null;
  break;
}

/* Opcode: CollSeq * * P4
**
** P4 is a pointer to a CollSeq struct. If the next call to a user function
** or aggregate calls sqlite3GetFuncCollSeq(), this collation sequence will

case OP_BitAnd:                 /* same as TK_BITAND, in1, in2, out3 */
case OP_BitOr:                  /* same as TK_BITOR, in1, in2, out3 */
case OP_ShiftLeft:              /* same as TK_LSHIFT, in1, in2, out3 */
case OP_ShiftRight: {           /* same as TK_RSHIFT, in1, in2, out3 */
  i64 a, b;

  if( (pIn1->flags | pIn2->flags) & MEM_Null ){
    Release(pOut);
    pOut->flags = MEM_Null;
    break;
  }
  a = sqlite3VdbeIntValue(pIn2);
  b = sqlite3VdbeIntValue(pIn1);
  switch( pOp->opcode ){
    case OP_BitAnd:      a &= b;     break;
    case OP_BitOr:       a |= b;     break;
    case OP_ShiftLeft:   a <<= b;    break;

    case OP_ShiftRight:  a >>= b;    break;
    default:   /* CANT HAPPEN */     break;
  }
  Release(pOut);
  pOut->u.i = a;
  pOut->flags = MEM_Int;
  break;
}

      i64 payloadSize64;
      sqlite3BtreeKeySize(pCrsr, &payloadSize64);
      payloadSize = payloadSize64;
    }else{
      sqlite3BtreeDataSize(pCrsr, &payloadSize);
    }
    nField = pC->nField;

  }else if( pC->pseudoTable ){
    /* The record is the sole entry of a pseudo-table */
    payloadSize = pC->nData;
    zRec = pC->pData;
    pC->cacheStatus = CACHE_STALE;
    assert( payloadSize==0 || zRec!=0 );
    nField = pC->nField;
    pCrsr = 0;
  }else{
    zRec = 0;
    payloadSize = 0;
    pCrsr = 0;
    nField = 0;
  }

  /* If payloadSize is 0, then just store a NULL */
  if( payloadSize==0 ){
    assert( pDest->flags==MEM_Null );
    goto op_column_out;
  }
  if( payloadSize>SQLITE_MAX_LENGTH ){
    goto too_big;
  }

  assert( p2<nField );

  /* Read and parse the table header.  Store the results of the parse
  ** into the record header cache fields of the cursor.
  */
  if( pC && pC->cacheStatus==p->cacheCtr ){
    aType = pC->aType;
    aOffset = pC->aOffset;
  }else{
    u8 *zIdx;        /* Index into header */
    u8 *zEndHdr;     /* Pointer to first byte after the header */
    u32 offset;      /* Offset into the data */
    int szHdrSz;     /* Size of the header size field at start of record */

  */
  for(pRec=pData0; pRec<=pLast; pRec++){
    int len;
    if( zAffinity ){
      applyAffinity(pRec, zAffinity[pRec-pData0], encoding);
    }
    if( pRec->flags&MEM_Zero && pRec->n>0 ){
      ExpandBlob(pRec);
    }
    serial_type = sqlite3VdbeSerialType(pRec, file_format);
    len = sqlite3VdbeSerialTypeLen(serial_type);
    nData += len;
    nHdr += sqlite3VarintLen(serial_type);
    if( pRec->flags & MEM_Zero ){
      /* Only pure zero-filled BLOBs can be input to this Opcode.

** commit when the VDBE halts.
**
** The statement is begun on the database file with index P1.  The main
** database file has an index of 0 and the file used for temporary tables
** has an index of 1.
*/
case OP_Statement: {

  int i = pOp->p1;
  Btree *pBt;
  if( i>=0 && i<db->nDb && (pBt = db->aDb[i].pBt)!=0
        && (db->autoCommit==0 || db->activeVdbeCnt>1) ){

    assert( sqlite3BtreeIsInTrans(pBt) );
    assert( (p->btreeMask & (1<<i))!=0 );
    if( !sqlite3BtreeIsInStmt(pBt) ){
      rc = sqlite3BtreeBeginStmt(pBt);
      p->openedStatement = 1;
    }
  }

    p2 = pIn2->u.i;
    assert( p2>=2 );
  }
  assert( i>=0 );
  pCur = allocateCursor(p, i, iDb);
  if( pCur==0 ) goto no_mem;
  pCur->nullRow = 1;
  if( pX==0 ) break;
  /* We always provide a key comparison function.  If the table being
  ** opened is of type INTKEY, the comparision function will be ignored. */
  rc = sqlite3BtreeCursor(pX, p2, wrFlag,
           sqlite3VdbeRecordCompare, pOp->p4.p,
           &pCur->pCursor);
  if( pOp->p4type==P4_KEYINFO ){
    pCur->pKeyInfo = pOp->p4.pKeyInfo;

/* Opcode: Close P1 * * * *
**
** Close a cursor previously opened as P1.  If P1 is not
** currently open, this instruction is a no-op.
*/
case OP_Close: {
  int i = pOp->p1;
  if( i>=0 && i<p->nCursor ){
    sqlite3VdbeFreeCursor(p, p->apCsr[i]);
    p->apCsr[i] = 0;
  }
  break;
}

/* Opcode: MoveGe P1 P2 P3 * *
**
** Use the value in register P3 as a key.  Reposition
** cursor P1 so that it points to the smallest entry that is greater

** This instruction only works on tables.  The equivalent instruction
** for indices is OP_IdxInsert.
*/
case OP_Insert: {
  Mem *pData = &p->aMem[pOp->p2];
  Mem *pKey = &p->aMem[pOp->p3];


  int i = pOp->p1;
  Cursor *pC;
  assert( i>=0 && i<p->nCursor );

  assert( p->apCsr[i]!=0 );



  REGISTER_TRACE(pOp->p2, pData);
  REGISTER_TRACE(pOp->p3, pKey);
  if( ((pC = p->apCsr[i])->pCursor!=0 || pC->pseudoTable) ){
    i64 iKey;   /* The integer ROWID or key for the record to be inserted */

    assert( pKey->flags & MEM_Int );
    assert( pC->isTable );
    iKey = intToKey(pKey->u.i);

    if( pOp->p5 & OPFLAG_NCHANGE ) p->nChange++;
    if( pOp->p5 & OPFLAG_LASTROWID ) db->lastRowid = pKey->u.i;
    if( pC->nextRowidValid && pKey->u.i>=pC->nextRowid ){
      pC->nextRowidValid = 0;
    }
    if( pData->flags & MEM_Null ){
      pData->z = 0;
      pData->n = 0;
    }else{
      assert( pData->flags & (MEM_Blob|MEM_Str) );
    }
    if( pC->pseudoTable ){
      sqlite3_free(pC->pData);
      pC->iKey = iKey;
      pC->nData = pData->n;
      if( pData->flags & MEM_Dyn ){
        pC->pData = pData->z;
        pData->flags &= ~MEM_Dyn;
        pData->flags |= MEM_Ephem;
      }else{
        pC->pData = sqlite3_malloc( pC->nData+2 );
        if( !pC->pData ) goto no_mem;
        memcpy(pC->pData, pData->z, pC->nData);
        pC->pData[pC->nData] = 0;
        pC->pData[pC->nData+1] = 0;
      }
      pC->nullRow = 0;
    }else{
      int nZero;
      if( pData->flags & MEM_Zero ){
        nZero = pData->u.i;
      }else{
        nZero = 0;
      }
      rc = sqlite3BtreeInsert(pC->pCursor, 0, iKey,
                              pData->z, pData->n, nZero,
                              pOp->p5 & OPFLAG_APPEND);
    }
    
    pC->rowidIsValid = 0;
    pC->deferredMoveto = 0;
    pC->cacheStatus = CACHE_STALE;

    /* Invoke the update-hook if required. */
    if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
      const char *zDb = db->aDb[pC->iDb].zName;
      const char *zTbl = pOp->p4.z;
      int op = ((pOp->p5 & OPFLAG_ISUPDATE) ? SQLITE_UPDATE : SQLITE_INSERT);
      assert( pC->isTable );
      db->xUpdateCallback(db->pUpdateArg, op, zDb, zTbl, iKey);
      assert( pC->iDb>=0 );
    }
  }

  break;
}

/* Opcode: Delete P1 P2 * P4 *
**
** Delete the record at which the P1 cursor is currently pointing.
**

  assert( pC!=0 );
  if( pC->nullRow ){
    pOut->flags = MEM_Null;
  }else if( pC->pCursor!=0 ){
    BtCursor *pCrsr = pC->pCursor;
    rc = sqlite3VdbeCursorMoveto(pC);
    if( rc ) goto abort_due_to_error;
    if( pC->nullRow ){
      pOut->flags = MEM_Null;
      break;
    }else if( pC->isIndex ){
      i64 n64;
      assert( !pC->isTable );
      sqlite3BtreeKeySize(pCrsr, &n64);
      if( n64>SQLITE_MAX_LENGTH ){
        goto too_big;
      }
      n = n64;

      pOut->z = z;
    }
    if( pC->isIndex ){
      rc = sqlite3BtreeKey(pCrsr, 0, n, pOut->z);
    }else{
      rc = sqlite3BtreeData(pCrsr, 0, n, pOut->z);
    }

  }else if( pC->pseudoTable ){
    pOut->n = pC->nData;
    assert( pC->nData<=SQLITE_MAX_LENGTH );
    pOut->z = pC->pData;
    pOut->flags = MEM_Blob|MEM_Ephem;
  }else{
    pOut->flags = MEM_Null;
  }
  pOut->enc = SQLITE_UTF8;  /* In case the blob is ever cast to text */
  UPDATE_MAX_BLOBSIZE(pOut);
  break;
}

/* Opcode: Rowid P1 P2 * * *

  assert( pC!=0 );
  rc = sqlite3VdbeCursorMoveto(pC);
  if( rc ) goto abort_due_to_error;
  if( pC->rowidIsValid ){
    v = pC->lastRowid;
  }else if( pC->pseudoTable ){
    v = keyToInt(pC->iKey);
  }else if( pC->nullRow || pC->pCursor==0 ){
    /* Leave the rowid set to a NULL */
    break;
  }else{
    assert( pC->pCursor!=0 );
    sqlite3BtreeKeySize(pC->pCursor, &v);
    v = keyToInt(v);
  }

** If P2 is 0 or if the table or index is not empty, fall through
** to the following instruction.
*/
case OP_Last: {        /* jump */
  int i = pOp->p1;
  Cursor *pC;
  BtCursor *pCrsr;


  assert( i>=0 && i<p->nCursor );
  pC = p->apCsr[i];
  assert( pC!=0 );
  if( (pCrsr = pC->pCursor)!=0 ){
    int res;
    rc = sqlite3BtreeLast(pCrsr, &res);
    pC->nullRow = res;
    pC->deferredMoveto = 0;
    pC->cacheStatus = CACHE_STALE;
    if( res && pOp->p2>0 ){
      pc = pOp->p2 - 1;
    }
  }else{
    pC->nullRow = 0;
  }
  break;
}


/* Opcode: Sort P1 P2 * * *
**

    pC->atFirst = res==0;
    pC->deferredMoveto = 0;
    pC->cacheStatus = CACHE_STALE;
  }else{
    res = 1;
  }
  pC->nullRow = res;

  if( res && pOp->p2>0 ){
    pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: Next P1 P2 * * *
**

      pOut->flags = MEM_Int;
      pOut->u.i = rowid;
    }
  }
  break;
}

/* Opcode: IdxGT P1 P2 P3 * *
**
** The value in register P3 is an index entry that omits the ROWID.  Compare
** the value in register P3 against the index that P1 is currently pointing to.
** Ignore the ROWID on the P1 index.
**
** The P3 value might have fewer columns that P1 index.
**
** If the P1 index entry is greater than the value in register P3
** then jump to P2.  Otherwise fall through to the next instruction.
*/
/* Opcode: IdxGE P1 P2 P3 * P5
**
** The value in register P3 is an index entry that omits the ROWID.  Compare
** this value against the index that P1 is currently pointing to.
** Ignore the ROWID on the P1 index.
**
** If the P1 index entry is greater than or equal to the value in 

**
** If P5 is non-zero then the
** index taken from register P3 is temporarily increased by
** an epsilon prior to the comparison.  This makes the opcode work
** like IdxLE.
*/
case OP_IdxLT:          /* jump, in3 */
case OP_IdxGT:          /* jump, in3 */
case OP_IdxGE: {        /* jump, in3 */
  int i= pOp->p1;
  Cursor *pC;

  assert( i>=0 && i<p->nCursor );
  assert( p->apCsr[i]!=0 );
  if( (pC = p->apCsr[i])->pCursor!=0 ){
    int res;
 
    assert( pIn3->flags & MEM_Blob );  /* Created using OP_MakeRecord */
    assert( pC->deferredMoveto==0 );
    ExpandBlob(pIn3);

    *pC->pIncrKey = pOp->p5!=0;
    assert( pOp->opcode!=OP_IdxGT || pOp->p5==0 );
    rc = sqlite3VdbeIdxKeyCompare(pC, pIn3->n, (u8*)pIn3->z, &res);
    *pC->pIncrKey = 0;
    if( rc!=SQLITE_OK ){
      break;
    }
    if( pOp->opcode==OP_IdxLT ){
      res = -res;

    }else if( pOp->opcode==OP_IdxGE ){
      res++;
    }
    if( res>0 ){
      pc = pOp->p2 - 1 ;
    }
  }
  break;

  }
  aRoot[j] = 0;
  assert( pOp->p5<db->nDb );
  assert( (p->btreeMask & (1<<pOp->p5))!=0 );
  z = sqlite3BtreeIntegrityCheck(db->aDb[pOp->p5].pBt, aRoot, nRoot,
                                 pnErr->u.i, &nErr);
  pnErr->u.i -= nErr;
  Release(pIn1);
  if( nErr==0 ){
    assert( z==0 );
    pIn1->flags = MEM_Null;
  }else{
    pIn1->z = z;
    pIn1->n = strlen(z);
    pIn1->flags = MEM_Str | MEM_Dyn | MEM_Term;
    pIn1->xDel = 0;
  }
  pIn1->enc = SQLITE_UTF8;

        registerTrace(p->trace, pOp->p3, pOut);
      }
    }
#endif  /* SQLITE_DEBUG */
#endif  /* NDEBUG */
  }  /* The end of the for(;;) loop the loops through opcodes */

  /* If we reach this point, it means that execution is finished.

  */
vdbe_halt:
  if( rc ){
    p->rc = rc;
    rc = SQLITE_ERROR;
  }else{
    rc = SQLITE_DONE;
  }
  sqlite3VdbeHalt(p);

  /* This is the only way out of this procedure.  We have to
  ** release the mutexes on btrees that were acquired at the
  ** top. */
vdbe_return:
  sqlite3BtreeMutexArrayLeave(&p->aMutex);
  return rc;

  /* Jump to here if a string or blob larger than SQLITE_MAX_LENGTH
  ** is encountered.
  */
too_big:
  sqlite3SetString(&p->zErrMsg, "string or blob too big", (char*)0);
  rc = SQLITE_TOOBIG;
  goto vdbe_halt;

  /* Jump to here if a malloc() fails.
  */
no_mem:
  db->mallocFailed = 1;
  sqlite3SetString(&p->zErrMsg, "out of memory", (char*)0);
  rc = SQLITE_NOMEM;
  goto vdbe_halt;

  /* Jump to here for an SQLITE_MISUSE error.
  */
abort_due_to_misuse:
  rc = SQLITE_MISUSE;
  /* Fall thru into abort_due_to_error */

  /* Jump to here for any other kind of fatal error.  The "rc" variable
  ** should hold the error number.
  */
abort_due_to_error:
  if( p->zErrMsg==0 ){
    if( db->mallocFailed ) rc = SQLITE_NOMEM;
    sqlite3SetString(&p->zErrMsg, sqlite3ErrStr(rc), (char*)0);
  }
  goto vdbe_halt;

  /* Jump to here if the sqlite3_interrupt() API sets the interrupt
  ** flag.
  */
abort_due_to_interrupt:
  assert( db->u1.isInterrupted );
  if( db->magic!=SQLITE_MAGIC_BUSY ){
    rc = SQLITE_MISUSE;
  }else{
    rc = SQLITE_INTERRUPT;
  }
  p->rc = rc;
  sqlite3SetString(&p->zErrMsg, sqlite3ErrStr(rc), (char*)0);
  goto vdbe_halt;
}

    return n>SQLITE_MAX_LENGTH;
  }
  return 0; 
}

/*
** Make an shallow copy of pFrom into pTo.  Prior contents of
** pTo are overwritten.  The pFrom->z field is not duplicated.  If
** pFrom->z is used, then pTo->z points to the same thing as pFrom->z
** and flags gets srcType (either MEM_Ephem or MEM_Static).
*/
void sqlite3VdbeMemShallowCopy(Mem *pTo, const Mem *pFrom, int srcType){

  memcpy(pTo, pFrom, sizeof(*pFrom)-sizeof(pFrom->zShort));
  pTo->xDel = 0;
  if( pTo->flags & (MEM_Str|MEM_Blob) ){
    pTo->flags &= ~(MEM_Dyn|MEM_Static|MEM_Short|MEM_Ephem);
    assert( srcType==MEM_Ephem || srcType==MEM_Static );
    pTo->flags |= srcType;
  }
}

/*
** Make a full copy of pFrom into pTo.  Prior contents of pTo are
** freed before the copy is made.
*/
int sqlite3VdbeMemCopy(Mem *pTo, const Mem *pFrom){
  int rc;
  if( pTo->flags & MEM_Dyn ){
    sqlite3VdbeMemRelease(pTo);
  }
  sqlite3VdbeMemShallowCopy(pTo, pFrom, MEM_Ephem);
  if( pTo->flags & MEM_Ephem ){
    rc = sqlite3VdbeMemMakeWriteable(pTo);
  }else{
    rc = SQLITE_OK;
  }
  return rc;