SQLite

    /* Code that appears at the end of the integrity check.  If no error
    ** messages have been generated, output OK.  Otherwise output the
    ** error message
    */
    static const int iLn = VDBE_OFFSET_LINENO(2);
    static const VdbeOpList endCode[] = {
      { OP_IfNeg,       1, 0,        0},    /* 0 */

      { OP_String8,     0, 3,        0},    /* 1 */
      { OP_ResultRow,   3, 1,        0},
    };

    int isQuick = (sqlite3Tolower(zLeft[0])=='q');

    /* If the PRAGMA command was of the form "PRAGMA <db>.integrity_check",
    ** then iDb is set to the index of the database identified by <db>.

          sqlite3VdbeAddOp3(v, OP_Concat, 3, 2, 7);
          sqlite3VdbeAddOp2(v, OP_ResultRow, 7, 1);
        }
#endif /* SQLITE_OMIT_BTREECOUNT */
      } 
    }
    addr = sqlite3VdbeAddOpList(v, ArraySize(endCode), endCode, iLn);
    sqlite3VdbeChangeP3(v, addr, -mxErr);
    sqlite3VdbeJumpHere(v, addr);
    sqlite3VdbeChangeP4(v, addr+1, "ok", P4_STATIC);
  }
  break;
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_UTF16
  /*
  **   PRAGMA encoding

    int addr;
    int iLimit;
    if( pSelect->iOffset ){
      iLimit = pSelect->iOffset+1;
    }else{
      iLimit = pSelect->iLimit;
    }
    addr = sqlite3VdbeAddOp3(v, OP_IfNotZero, iLimit, 0, -1); VdbeCoverage(v);
    sqlite3VdbeAddOp1(v, OP_Last, pSort->iECursor);
    sqlite3VdbeAddOp1(v, OP_Delete, pSort->iECursor);
    sqlite3VdbeJumpHere(v, addr);
  }
}

/*
** Add code to implement the OFFSET
*/
static void codeOffset(
  Vdbe *v,          /* Generate code into this VM */
  int iOffset,      /* Register holding the offset counter */
  int iContinue     /* Jump here to skip the current record */
){
  if( iOffset>0 ){
    int addr;
    addr = sqlite3VdbeAddOp3(v, OP_IfNeg, iOffset, 0, -1); VdbeCoverage(v);
    sqlite3VdbeGoto(v, iContinue);
    VdbeComment((v, "skip OFFSET records"));
    sqlite3VdbeJumpHere(v, addr);
  }
}

/*
** Add code that will check to make sure the N registers starting at iMem
** form a distinct entry.  iTab is a sorting index that holds previously
** seen combinations of the N values.  A new entry is made in iTab

** the reuse of the same limit and offset registers across multiple
** SELECT statements.
*/
static void computeLimitRegisters(Parse *pParse, Select *p, int iBreak){
  Vdbe *v = 0;
  int iLimit = 0;
  int iOffset;
  int addr1, n;
  if( p->iLimit ) return;

  /* 
  ** "LIMIT -1" always shows all rows.  There is some
  ** controversy about what the correct behavior should be.
  ** The current implementation interprets "LIMIT 0" to mean
  ** no rows.

    }
    if( p->pOffset ){
      p->iOffset = iOffset = ++pParse->nMem;
      pParse->nMem++;   /* Allocate an extra register for limit+offset */
      sqlite3ExprCode(pParse, p->pOffset, iOffset);
      sqlite3VdbeAddOp1(v, OP_MustBeInt, iOffset); VdbeCoverage(v);
      VdbeComment((v, "OFFSET counter"));
      addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iOffset); VdbeCoverage(v);
      sqlite3VdbeAddOp2(v, OP_Integer, 0, iOffset);
      sqlite3VdbeJumpHere(v, addr1);
      sqlite3VdbeAddOp3(v, OP_Add, iLimit, iOffset, iOffset+1);
      VdbeComment((v, "LIMIT+OFFSET"));
      addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iLimit); VdbeCoverage(v);
      sqlite3VdbeAddOp2(v, OP_Integer, -1, iOffset+1);
      sqlite3VdbeJumpHere(v, addr1);
    }
  }
}

#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** Return the appropriate collating sequence for the iCol-th column of

      p->pPrior = 0;
      p->iLimit = pPrior->iLimit;
      p->iOffset = pPrior->iOffset;
      if( p->iLimit ){
        addr = sqlite3VdbeAddOp1(v, OP_IfNot, p->iLimit); VdbeCoverage(v);
        VdbeComment((v, "Jump ahead if LIMIT reached"));
        if( p->iOffset ){
          int addr2;
          sqlite3VdbeAddOp3(v, OP_Add, p->iLimit, p->iOffset, p->iOffset+1);
          addr2 = sqlite3VdbeAddOp1(v, OP_IfPos, p->iOffset); VdbeCoverage(v);
          sqlite3VdbeAddOp2(v, OP_SCopy, p->iLimit, p->iOffset+1);
          sqlite3VdbeJumpHere(v, addr2);
          addr2 = sqlite3VdbeAddOp1(v, OP_IfPos, p->iLimit); VdbeCoverage(v);
          sqlite3VdbeAddOp2(v, OP_Integer, -1, p->iOffset+1);
          sqlite3VdbeJumpHere(v, addr2);
        }
      }
      explainSetInteger(iSub2, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, p, &dest);
      testcase( rc!=SQLITE_OK );
      pDelete = p->pPrior;
      p->pPrior = pPrior;

  if( pIn1->u.i<pIn2->u.i){
    pIn1->u.i = pIn2->u.i;
  }
  break;
}
#endif /* SQLITE_OMIT_AUTOINCREMENT */

/* Opcode: IfPos P1 P2 * * *
** Synopsis: if r[P1]>0 goto P2
**
** Register P1 must contain an integer.
** If the value of register P1 is 1 or greater, jump to P2 and
** add the literal value P3 to register P1.
**
** If the initial value of register P1 is less than 1, then the
** value is unchanged and control passes through to the next instruction.
*/
case OP_IfPos: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  VdbeBranchTaken( pIn1->u.i>0, 2);
  if( pIn1->u.i>0 ) goto jump_to_p2;



  break;
}

/* Opcode: IfNeg P1 P2 P3 * *
** Synopsis: r[P1]+=P3, if r[P1]<0 goto P2
**
** Register P1 must contain an integer.  Add literal P3 to the value in
** register P1 then if the value of register P1 is less than zero, jump to P2. 

*/
case OP_IfNeg: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  pIn1->u.i += pOp->p3;
  VdbeBranchTaken(pIn1->u.i<0, 2);
  if( pIn1->u.i<0 ) goto jump_to_p2;



  break;
}

/* Opcode: IfNotZero P1 P2 P3 * *
** Synopsis: if r[P1]!=0 then r[P1]+=P3, goto P2
**
** Register P1 must contain an integer.  If the content of register P1 is

** initially nonzero, then add P3 to P1 and jump to P2.  If register P1 is
** initially zero, leave it unchanged and fall through.
*/
case OP_IfNotZero: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  VdbeBranchTaken(pIn1->u.i<0, 2);
  if( pIn1->u.i ){
     pIn1->u.i += pOp->p3;
     goto jump_to_p2;
  }
  break;
}

/* Opcode: DecrJumpZero P1 P2 * * *
** Synopsis: if (--r[P1])==0 goto P2