SQLite

/*
** This function compares two index or table record keys in the same way
** as the sqlite3VdbeRecordCompare() routine. Unlike VdbeRecordCompare(),
** this function deserializes and compares values using the
** sqlite3VdbeSerialGet() and sqlite3MemCompare() functions. It is used
** in assert() statements to ensure that the optimized code in
** sqlite3VdbeRecordCompare() returns results with these two primitives.



*/
static int vdbeRecordCompareDebug(
  int nKey1, const void *pKey1, /* Left key */
  const UnpackedRecord *pPKey2  /* Right key */

){
  u32 d1;            /* Offset into aKey[] of next data element */
  u32 idx1;          /* Offset into aKey[] of next header element */
  u32 szHdr1;        /* Number of bytes in header */
  int i = 0;
  int rc = 0;
  const unsigned char *aKey1 = (const unsigned char *)pKey1;

    */
    rc = sqlite3MemCompare(&mem1, &pPKey2->aMem[i], pKeyInfo->aColl[i]);
    if( rc!=0 ){
      assert( mem1.zMalloc==0 );  /* See comment below */
      if( pKeyInfo->aSortOrder[i] ){
        rc = -rc;  /* Invert the result for DESC sort order. */
      }
      return rc;
    }
    i++;
  }while( idx1<szHdr1 && i<pPKey2->nField );

  /* No memory allocation is ever used on mem1.  Prove this using
  ** the following assert().  If the assert() fails, it indicates a
  ** memory leak and a need to call sqlite3VdbeMemRelease(&mem1).
  */
  assert( mem1.zMalloc==0 );

  /* rc==0 here means that one of the keys ran out of fields and
  ** all the fields up to that point were equal. Return the the default_rc
  ** value.  */
  return pPKey2->default_rc;








}
#endif

/*
** Both *pMem1 and *pMem2 contain string values. Compare the two values
** using the collation sequence pColl. As usual, return a negative , zero
** or positive value if *pMem1 is less than, equal to or greater than 

      rc = (serial_type!=0);
    }

    if( rc!=0 ){
      if( pKeyInfo->aSortOrder[i] ){
        rc = -rc;
      }
      assert( CORRUPT_DB
          || (rc<0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)<0)
          || (rc>0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)>0)
          || pKeyInfo->db->mallocFailed
      );
      assert( mem1.zMalloc==0 );  /* See comment below */
      return rc;
    }

    i++;
    pRhs++;
    d1 += sqlite3VdbeSerialTypeLen(serial_type);
    idx1 += sqlite3VarintLen(serial_type);
  }while( idx1<(unsigned)szHdr1 && i<pPKey2->nField && d1<=(unsigned)nKey1 );

  /* No memory allocation is ever used on mem1.  Prove this using
  ** the following assert().  If the assert() fails, it indicates a
  ** memory leak and a need to call sqlite3VdbeMemRelease(&mem1).  */
  assert( mem1.zMalloc==0 );

  /* rc==0 here means that one or both of the keys ran out of fields and
  ** all the fields up to that point were equal. Return the the default_rc
  ** value.  */
  assert( CORRUPT_DB 
       || pPKey2->default_rc==vdbeRecordCompareDebug(nKey1, pKey1, pPKey2) 
  );
  return pPKey2->default_rc;
}

/*
** This function is an optimized version of sqlite3VdbeRecordCompare() 
** that (a) the first field of pPKey2 is an integer, and (b) the 
** size-of-header varint at the start of (pKey1/nKey1) fits in a single

    res = sqlite3VdbeRecordCompare(nKey1, pKey1, pPKey2, 1);
  }else{
    /* The first fields of the two keys are equal and there are no trailing
    ** fields. Return pPKey2->default_rc in this case. */
    res = pPKey2->default_rc;
  }

  assert( (res==0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)==0)
       || (res<0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)<0)
       || (res>0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)>0)
       || CORRUPT_DB
  );
  return res;
}

/*
** This function is an optimized version of sqlite3VdbeRecordCompare() 
** that (a) the first field of pPKey2 is a string, that (b) the first field
** uses the collation sequence BINARY and (c) that the size-of-header varint 

    }else if( res>0 ){
      res = pPKey2->r2;
    }else{
      res = pPKey2->r1;
    }
  }

  assert( (res==0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)==0)
       || (res<0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)<0)
       || (res>0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)>0)
       || CORRUPT_DB
  );
  return res;
}

/*
** Return a pointer to an sqlite3VdbeRecordCompare() compatible function
** suitable for comparing serialized records to the unpacked record passed
** as the only argument.