My employer is asking to do an Active / Active SQL 2000 cluster to utilize
both servers. Problem is, I don't think SQL 2000 supports an Active/Active
solution because both would need access to the disk which isn't possible...
The only time an Active / Active cluster can work is when you have multiple
instances which allows Node A to use the disk for one instance and Node B to
utilize the disk for a different named instance.
Can someone clarify for me? Thanks.
Each instance of SQL Server will require its own disk resources. Thus, if
SQL1 owns E: then SQL2 cannot have an E: drive. SQL 2000 supports up to 16
instances within the same cluster. We don't use the term Active/Active any
more.
Tom
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
SQL Server MVP
Toronto, ON Canada
..
"burt_king" <burt_king@.yahoo.com> wrote in message
news:C926C991-9D66-4531-A5FF-912AEC097165@.microsoft.com...
My employer is asking to do an Active / Active SQL 2000 cluster to utilize
both servers. Problem is, I don't think SQL 2000 supports an Active/Active
solution because both would need access to the disk which isn't possible...
The only time an Active / Active cluster can work is when you have multiple
instances which allows Node A to use the disk for one instance and Node B to
utilize the disk for a different named instance.
Can someone clarify for me? Thanks.
|||"when you have multiple instances which allows Node A to use the disk for
one instance and Node B to utilize the disk for a different named instance."
--> correct
what you might want to look into is :
scalable shared databases, where multiple SQL 2005 (enterprise)
servers are accessing a read-only volume.
there are many restrictions to this
Please see ; http://support.microsoft.com/default.aspx?scid=kb;en-us;910378
for more info on this
"burt_king" <burt_king@.yahoo.com> wrote in message
news:C926C991-9D66-4531-A5FF-912AEC097165@.microsoft.com...
> My employer is asking to do an Active / Active SQL 2000 cluster to utilize
> both servers. Problem is, I don't think SQL 2000 supports an
Active/Active
> solution because both would need access to the disk which isn't
possible...
> The only time an Active / Active cluster can work is when you have
multiple
> instances which allows Node A to use the disk for one instance and Node B
to
> utilize the disk for a different named instance.
> Can someone clarify for me? Thanks.
> --
|||Each instance requires it own dedicated disk resources that cannot be
shared, and databases CANNOT be shared between instances. Those dedicated
resources cannot have the same drive assignment.
Instance A has SAN drive G, H,
Instance B has SAN drives M, N
Upon failover of Instance A, Physical computer B now runs both Instance B
AND Instance A, and Drives G, H, M, N.
This has been a very simplistic example, but hopefully you now understand a
bit better.
Arnie Rowland, Ph.D.
Westwood Consulting, Inc
Most good judgment comes from experience.
Most experience comes from bad judgment.
- Anonymous
You can't help someone get up a hill without getting a little closer to the
top yourself.
- H. Norman Schwarzkopf
"burt_king" <burt_king@.yahoo.com> wrote in message
news:C926C991-9D66-4531-A5FF-912AEC097165@.microsoft.com...
> My employer is asking to do an Active / Active SQL 2000 cluster to utilize
> both servers. Problem is, I don't think SQL 2000 supports an
> Active/Active
> solution because both would need access to the disk which isn't
> possible...
> The only time an Active / Active cluster can work is when you have
> multiple
> instances which allows Node A to use the disk for one instance and Node B
> to
> utilize the disk for a different named instance.
> Can someone clarify for me? Thanks.
> --
|||Roland, very clear, thank you.
Now, slightly off but still for clustering, how do I administer the
traditional sp_configure settings? I'm speaking of memory for myself but
that raised the larger question, How do I administer the server? I'd assume
through the virtual server name since on the back end the Master and MSDB are
really being written to by the Active node... Am I correct? If I want to
give the server more or less memory, can I do so through the Enterprise
manager interface?
"Arnie Rowland" wrote:
> Each instance requires it own dedicated disk resources that cannot be
> shared, and databases CANNOT be shared between instances. Those dedicated
> resources cannot have the same drive assignment.
> Instance A has SAN drive G, H,
> Instance B has SAN drives M, N
> Upon failover of Instance A, Physical computer B now runs both Instance B
> AND Instance A, and Drives G, H, M, N.
> This has been a very simplistic example, but hopefully you now understand a
> bit better.
> --
> Arnie Rowland, Ph.D.
> Westwood Consulting, Inc
> Most good judgment comes from experience.
> Most experience comes from bad judgment.
> - Anonymous
> You can't help someone get up a hill without getting a little closer to the
> top yourself.
> - H. Norman Schwarzkopf
>
> "burt_king" <burt_king@.yahoo.com> wrote in message
> news:C926C991-9D66-4531-A5FF-912AEC097165@.microsoft.com...
>
>
|||Each server in the cluster is still an independent server; configuration is
done the same way as a stand alone server. However, you need to configure
with the understanding that both instances MAY have to operate on the same
box.
So if the box has 8 GB of memory, then you don't assign all 8 GBs to the
default instance on that box. If you did, when there is a failover, there
will be no memory for the 'visiting' instance.
If InstanceA has a minimum memory of 4 GB, and Instance B also has a minimum
memory allocation of 4 GB, and the server only has 8 GB, then upon failover,
the 'visiting' instance will be memory starved and will most like not come
online. (You have to make sure that there is enough memory for the OS as
well.)
Let's say both boxes have 8 GB. InstanceA contains large, heavily used
databases, so it is allocated 5 GB as a maximum, and InstanceB is less
demanding, so it is allocated 2 GB as a maximum. Upon failover, the two
instances require 7 GB, and leave 1 GB for the OS and memory management.
'Bean counters' will complain since it appears that InstanceB only needs 3
GB for the server, and adding an addition 5 GB is seen as a waste. However,
you have to consider the cost of the 'unused' 5 GB on InstanceB as insurance
payments for future availability. (And the same for the 'unused' 2 GB on
InstanceA.)
Thing to remember with configuration, is that upon failover, all instances
must be able to work (albeit perhaps not performing quite as well) on one
box. Most Server wide configuration settings 'should' be the same. Memory is
the most common setting that is different between Instances.
Arnie Rowland, Ph.D.
Westwood Consulting, Inc
Most good judgment comes from experience.
Most experience comes from bad judgment.
- Anonymous
You can't help someone get up a hill without getting a little closer to the
top yourself.
- H. Norman Schwarzkopf
"burt_king" <burt_king@.yahoo.com> wrote in message
news:91DFAA5E-B271-4CA4-B6FE-727CA857BC39@.microsoft.com...[vbcol=seagreen]
> Roland, very clear, thank you.
> Now, slightly off but still for clustering, how do I administer the
> traditional sp_configure settings? I'm speaking of memory for myself but
> that raised the larger question, How do I administer the server? I'd
> assume
> through the virtual server name since on the back end the Master and MSDB
> are
> really being written to by the Active node... Am I correct? If I want to
> give the server more or less memory, can I do so through the Enterprise
> manager interface?
>
> "Arnie Rowland" wrote:
Showing posts with label supports. Show all posts
Showing posts with label supports. Show all posts
Tuesday, March 27, 2012
Monday, March 19, 2012
Clueless client who wants to create a table using reserved words
Hello all,
I have a database that supports two different applications.
For arguments sake I'll call them "intelligent app" and "clueless app"
The client that provided me the schema for the clueless app used reserved words as field names.
The words used are:
value, state, and time
I explained to the client that modifying them could prevent current/future issues.
The client is an "oracle" db (and in my mind should know better but ....) and responded back to me with the following:
BEGIN QUOTE
They are not currently reserved and there is no guarantee they will ever be reserved. In fact, the SQL server line eliminates as many words from the reserved list as they add with new releases. There are other words on the
possible future reserved keyword list that I do not wish to avoid either unless forced to some day, like depth, size, class, zone, level and others.
END QUOTE
Now for the assistance request, where can I find the documented ramifications of using reserved words?
I want to have my documentation (and my ducks lined up) when this clients portion of the app fails.
Any and all assistance is greatly appreciated.
T. Mullins'splain dat one again... Whyfor you have to be prepared when their Data Modeler's choices hit the fan?
SQL Server will gleefully tolerate them, as long as they are properly quoted using [], so what the heck do you care? The developers may revolt when their tools act up, but those column names aren't your choices, so they aren't your problems as far as I can see.
-PatP|||Do a search for "Reserved Keywords" in Books OnLine, and you should be presented with the current list of reserved words. One caution, I did come up with tw lists, one for C++ and one for T-SQL.
A quote from this article reads:
Although it is syntactically possible to use SQL Server reserved keywords as identifiers and object names in Transact-SQL scripts, this can be done only using delimited identifiers.
This is pretty much what Pat has said in his post, though.|||Gracias guys !
I knew of the BOL & MSDN info. I was hoping to have examples of apps that have crashed and burned due to poor design. :)
I think I'll wait in the tall grass ......
Regards to all.
tam
Originally posted by MCrowley
Do a search for "Reserved Keywords" in Books OnLine, and you should be presented with the current list of reserved words. One caution, I did come up with tw lists, one for C++ and one for T-SQL.
A quote from this article reads:
Although it is syntactically possible to use SQL Server reserved keywords as identifiers and object names in Transact-SQL scripts, this can be done only using delimited identifiers.
This is pretty much what Pat has said in his post, though.|||Oh, there are fabulous stories that go from the 1970s into the 1990s, but they peter out pretty quickly there. By that point in time, nearly everybody in the compiler/database/toolset community had abandoned the L-R grammer parsers for yacc or its equivalent, which allowed them to quickly and easily make it possible to make a product's entire grammer "quote sensistive". That change allowed the product vendors to make it possible for the user to "un-reserve" words that were otherwise reserved by quoting them somehow.
That change, combined with wider use of code-generators (sometimes by different names, but code generators nonetheless) made it relatively easy to "dodge the bullet" of reserved words.
It can still be a pain in the posterior, but it is no longer a case of Mohammed and the Mountian. Now the developer can work around the reserved-word problem if they choose to do so.
-PatP
I have a database that supports two different applications.
For arguments sake I'll call them "intelligent app" and "clueless app"
The client that provided me the schema for the clueless app used reserved words as field names.
The words used are:
value, state, and time
I explained to the client that modifying them could prevent current/future issues.
The client is an "oracle" db (and in my mind should know better but ....) and responded back to me with the following:
BEGIN QUOTE
They are not currently reserved and there is no guarantee they will ever be reserved. In fact, the SQL server line eliminates as many words from the reserved list as they add with new releases. There are other words on the
possible future reserved keyword list that I do not wish to avoid either unless forced to some day, like depth, size, class, zone, level and others.
END QUOTE
Now for the assistance request, where can I find the documented ramifications of using reserved words?
I want to have my documentation (and my ducks lined up) when this clients portion of the app fails.
Any and all assistance is greatly appreciated.
T. Mullins'splain dat one again... Whyfor you have to be prepared when their Data Modeler's choices hit the fan?
SQL Server will gleefully tolerate them, as long as they are properly quoted using [], so what the heck do you care? The developers may revolt when their tools act up, but those column names aren't your choices, so they aren't your problems as far as I can see.
-PatP|||Do a search for "Reserved Keywords" in Books OnLine, and you should be presented with the current list of reserved words. One caution, I did come up with tw lists, one for C++ and one for T-SQL.
A quote from this article reads:
Although it is syntactically possible to use SQL Server reserved keywords as identifiers and object names in Transact-SQL scripts, this can be done only using delimited identifiers.
This is pretty much what Pat has said in his post, though.|||Gracias guys !
I knew of the BOL & MSDN info. I was hoping to have examples of apps that have crashed and burned due to poor design. :)
I think I'll wait in the tall grass ......
Regards to all.
tam
Originally posted by MCrowley
Do a search for "Reserved Keywords" in Books OnLine, and you should be presented with the current list of reserved words. One caution, I did come up with tw lists, one for C++ and one for T-SQL.
A quote from this article reads:
Although it is syntactically possible to use SQL Server reserved keywords as identifiers and object names in Transact-SQL scripts, this can be done only using delimited identifiers.
This is pretty much what Pat has said in his post, though.|||Oh, there are fabulous stories that go from the 1970s into the 1990s, but they peter out pretty quickly there. By that point in time, nearly everybody in the compiler/database/toolset community had abandoned the L-R grammer parsers for yacc or its equivalent, which allowed them to quickly and easily make it possible to make a product's entire grammer "quote sensistive". That change allowed the product vendors to make it possible for the user to "un-reserve" words that were otherwise reserved by quoting them somehow.
That change, combined with wider use of code-generators (sometimes by different names, but code generators nonetheless) made it relatively easy to "dodge the bullet" of reserved words.
It can still be a pain in the posterior, but it is no longer a case of Mohammed and the Mountian. Now the developer can work around the reserved-word problem if they choose to do so.
-PatP
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