KSAM locks vs C-ISAM locks

Wed, 30 Jul 2003 06:28:10 -0400

This message is in MIME format. Since your mail reader does not understand
this format, some or all of this message may not be legible.

------_=_NextPart_001_01C35685.46289650
Content-Type: text/plain

Set LOCK/NOLOCK is an MPE specific option based on how the file system (both
MPE and KSAM files) works. SET LOCK says that the file open is such that it
allows locking (i.e. locking enabled). However, this does not necessarily
mean that the file is locked. SET NOLOCK says that the file open is such
that it does not allow locking.

The reason for this option is that opens in MPE must be consistent. In other
words, if I open a file with locking enabled, then when you open the file,
you must also have locking enabled. I know it may seem strange not to have
locking enabled, but it is an MPE option.

Other platforms do not need this option because the operating systems don't
have the option. Locking is always enabled.

As for the actual locking mechanisms, both KSAM and C-ISAM allow file level
locks. C-ISAM also allows record level locks while KSAM does not.

So unless you're using SET NOLOCK (because SET LOCK is the default) your
KSAM locking should translate over to C-ISAM with no changes.

Bob Deskin              
Product Manager, Application Development Tools
Cognos Inc. 3755 Riverside Drive, Ottawa ON K1G 4K9 CANADA
bob.deskin@cognos.com (613) 738-1338 ext 7268

-----Original Message-----
From: Jerry Finn [mailto:finnjj@telefonica.net]
Sent: July 30, 2003 4:07 AM
To: powerh-l@lists.swau.edu
Subject: KSAM locks vs C-ISAM locks

I'm trying to find the equivalent to SET LOCK/SET NOLOCK for
MPE KSAM files for C-ISAM on UNIX. I'm working on a move from
MPE to UNIX and we want to move the KSAM files to C-ISAM. 

How would I do locks with C-ISAM that I do for KSAM?

-- 

Jerry Finn
finnjj@telefonica.net
= = = = = = = = = = = = = = = = = = = = = = = = = = = =
Mailing list: powerh-l@lists.swau.edu
Subscribe: "subscribe" in message body to powerh-l-request@lists.swau.edu
Unsubscribe: "unsubscribe <password>" in message body to
powerh-l-request@lists.swau.edu
http://lists.swau.edu/mailman/listinfo/powerh-l
This list is closed, thus to post to the list you must be a subscriber.

Join us at Cognos' biggest event of the year Enterprise 2003, The Cognos
Business Forum.  Taking place in over 25 cities around the world, it's an
opportunity for Business and IT leaders to learn about strategies for
driving performance. Visit http://www.cognos.com/enterprise03 for more
details. 

This message may contain privileged and/or confidential information.  If you
have received this e-mail in error or are not the intended recipient, you
may not use, copy, disseminate or distribute it; do not open any
attachments, delete it immediately from your system and notify the sender
promptly by e-mail that you have done so.  Thank you.

------_=_NextPart_001_01C35685.46289650
Content-Type: text/html
Content-Transfer-Encoding: quoted-printable

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
<HTML>
<HEAD>
<META HTTP-EQUIV=3D"Content-Type" CONTENT=3D"text/html; =
charset=3DUS-ASCII">
<META NAME=3D"Generator" CONTENT=3D"MS Exchange Server version =
5.5.2654.89">
<TITLE>RE: KSAM locks vs C-ISAM locks</TITLE>
</HEAD>
<BODY>

Set LOCK/NOLOCK is an MPE specific option based on =
how the file system (both MPE and KSAM files) works. SET LOCK says that =
the file open is such that it allows locking (i.e. locking enabled). =
However, this does not necessarily mean that the file is locked. SET =
NOLOCK says that the file open is such that it does not allow =
locking.

The reason for this option is that opens in MPE must =
be consistent. In other words, if I open a file with locking enabled, =
then when you open the file, you must also have locking enabled. I know =
it may seem strange not to have locking enabled, but it is an MPE =
option.

Other platforms do not need this option because the =
operating systems don't have the option. Locking is always =
enabled.

As for the actual locking mechanisms, both KSAM and =
C-ISAM allow file level locks. C-ISAM also allows record level locks =
while KSAM does not.

<P><FONT SIZE=3D2>So unless you're using SET NOLOCK (because SET LOCK =
is the default) your KSAM locking should translate over to C-ISAM with =
no changes.</FONT></P>

Bob =
Deskin&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;=
&nbsp;&nbsp; 
 Product Manager, Application Development =
Tools
 Cognos Inc. 3755 Riverside Drive, Ottawa ON K1G 4K9 =
CANADA
 bob.deskin@cognos.com (613) 738-1338 ext 7268

<P><FONT SIZE=3D2>-----Original Message-----</FONT>
<BR><FONT SIZE=3D2>From: Jerry Finn [<A =
HREF=3D"mailto:finnjj@telefonica.net">mailto:finnjj@telefonica.net</A>]<=
/FONT>
<BR><FONT SIZE=3D2>Sent: July 30, 2003 4:07 AM</FONT>
<BR><FONT SIZE=3D2>To: powerh-l@lists.swau.edu</FONT>
<BR><FONT SIZE=3D2>Subject: KSAM locks vs C-ISAM locks</FONT>
</P>
<BR>
<BR>

I'm trying to find the equivalent to SET LOCK/SET =
NOLOCK for
 MPE KSAM files for C-ISAM on UNIX. I'm working on a =
move from
 MPE to UNIX and we want to move the KSAM files to =
C-ISAM.

<P><FONT SIZE=3D2>How would I do locks with C-ISAM that I do for =
KSAM?</FONT>
</P>

<P><FONT SIZE=3D2>-- </FONT>
</P>

<P><FONT SIZE=3D2>Jerry Finn</FONT>
<BR><FONT SIZE=3D2>finnjj@telefonica.net</FONT>
<BR><FONT SIZE=3D2>=3D =3D =3D =3D =3D =3D =3D =3D =3D =3D =3D =3D =3D =
=3D =3D =3D =3D =3D =3D =3D =3D =3D =3D =3D =3D =3D =3D =3D</FONT>
<BR><FONT SIZE=3D2>Mailing list: powerh-l@lists.swau.edu</FONT>
<BR><FONT SIZE=3D2>Subscribe: &quot;subscribe&quot; in message body to =
powerh-l-request@lists.swau.edu</FONT>
<BR><FONT SIZE=3D2>Unsubscribe: &quot;unsubscribe =
&lt;password&gt;&quot; in message body to =
powerh-l-request@lists.swau.edu</FONT>
<BR><FONT SIZE=3D2><A =
HREF=3D"http://lists.swau.edu/mailman/listinfo/powerh-l" =
TARGET=3D"_blank">http://lists.swau.edu/mailman/listinfo/powerh-l</A></F=
ONT>
<BR><FONT SIZE=3D2>This list is closed, thus to post to the list you =
must be a subscriber.</FONT>
</P>

Join us at Cognos' biggest event of the year =
Enterprise 2003, The Cognos Business Forum.&nbsp; Taking place in =
over 25 cities around the world, it's an opportunity for Business and =
IT leaders to learn about strategies for driving performance. Visit =
<A HREF=3D"http://www.cognos.com/enterprise03" =
TARGET=3D"_blank">http://www.cognos.com/enterprise03</A> for more =
details.

<P><FONT SIZE=3D2>This message may contain privileged and/or =
confidential information.&nbsp; If you have received this e-mail in =
error or are not the intended recipient, you may not use, copy, =
disseminate or distribute it; do not open any attachments, delete it =
immediately from your system and notify the sender promptly by e-mail =
that you have done so.&nbsp; Thank you.</FONT></P>

</BODY>
</HTML>
------_=_NextPart_001_01C35685.46289650--