Problem : Mysql

1. Foreign Key concept is not working on MySQL version
4.1.15-max .
Actually I made two tables and I was able to "delete &
update" from primary key value even if those values are
present as a foreign key in another table.


2. Another problem is with _rowid. It only works when we
create Integer Primary key other wise it doesn't work.

How can we differentiate two rows when no primary key is
defined and both the rows contains same data. I can do in
Oracle with rowid.

how can we delete all those duplicate records in a table
which doesn't contain primary key or doesn't contain
numbered primary key. this can be done in oracle by rowid
but this can't be done in mysql. Plz give me solution at
earlist.

Regards,
Vipin Chandna

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RE: Problem : Mysql

Vipin Chandna,

You may already have received replies to your question but if so, I =
guess
they may have been private replies.

With regard to your question about rowid:

MySQL doesn't require record uniqueness but allows the database designer =
to
include an auto increment field which provides the same function but at =
a
user level. My impression is that the MySQL designers felt that this
provided the same functionality as the ROWID that Oracle provides. I =
can't
speak for all application interface methods, but in Visual Basic ADO, =
the
LastInsertID variable is stored in the connection object and is =
accessible
as an attribute. Presumably this carries over to other application =
access
methods.

If you add a field to your record such as MAINKEY (or whatever name you
want) with a type of bigint and an attribute of auto_increment you'll be
able to access this variable (LastInsertID) after an INSERT command to =
get
the equivalent of the Oracle ROWID variable. This also allows =
uniqueness in
indexing by concatenating it to any other index variables being used =
that
need uniqueness.

If I'm incorrect in what I've said, I hope others will correct any
misconceptions I may be causing.

Hope this helps.

Regards.



Lawson
lawson@vrtinc.com
+1(480)308-0641 (Voice)
+1(602)996-0376 (Fax)
=20

-----Original Message-----
From: vipin.chandna@monster.co.in [mailto:vipin.chandna@monster.co.in]=20
Sent: Wednesday, September 13, 2006 12:44 AM
To: myodbc@lists.mysql.com
Subject: Problem : Mysql


1. Foreign Key concept is not working on MySQL version
4.1.15-max .
Actually I made two tables and I was able to "delete &
update" from primary key value even if those values are
present as a foreign key in another table.


2. Another problem is with _rowid. It only works when we
create Integer Primary key other wise it doesn't work.

How can we differentiate two rows when no primary key is
defined and both the rows contains same data. I can do in
Oracle with rowid.

how can we delete all those duplicate records in a table
which doesn't contain primary key or doesn't contain
numbered primary key. this can be done in oracle by rowid
but this can't be done in mysql. Plz give me solution at
earlist.

Regards,
Vipin Chandna

--=20
MySQL ODBC Mailing List
For list archives: http://lists.mysql.com/myodbc
To unsubscribe: =
http://lists.mysql.com/myodbc?unsub=3Dlawson@vrtinc.com


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