Re: Doubts about oid

Hi,
> Even in Oracle, I don't believe rowid bypasses
> indexes, its more like an implicit SERIAL PRIMARY KEY field.
Well, I understand the point is not very relevant, since oid is not
similar to rowid. In Oracle, index scans are bypassed if we use rowid.

1)Access by unique index

SQL> select * from myt where id=200;
Execution Plan
----------------------------------------------------------
Plan hash value: 1325982734

--------------------------------------------------------------------------------

----

| Id | Operation | Name | Rows | Bytes | Cost (%CPU)|
Time
|

--------------------------------------------------------------------------------

----

| 0 | SELECT STATEMENT | | 1 | 65 | 1 (0)|
00:00:

01 |

| 1 | TABLE ACCESS BY INDEX ROWID| MYT | 1 | 65 | 1 (0)|
00:00:

01 |

|* 2 | INDEX UNIQUE SCAN | MYDX | 1 | | 1 (0)|
00:00:

01 |

--------------------------------------------------------------------------------

2) Access by rowid
SQL> select * from myt where rowid='AAAH9iAAEAAAAafADH';

ID
----------
NAME
--------------------------------------------------------------------------------

200
REFCON$

Execution Plan
----------------------------------------------------------
Plan hash value: 4204525950

--------------------------------------------------------------------------------

---

| Id | Operation | Name | Rows | Bytes | Cost (%CPU)|
Time
|

--------------------------------------------------------------------------------

---

| 0 | SELECT STATEMENT | | 1 | 77 | 1 (0)|
00:00:0

1 |

| 1 | TABLE ACCESS BY USER ROWID| MYT | 1 | 77 | 1 (0)|
00:00:0

Regards,
Jayadevan

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