asp - web application - DB ?

[abcd]

I have an asp based web applicaiton and that is targeted to be used by
intranet users say 10-500 or may be more. Currently, I have prototyped my
Web application using MS Access as my backend. Can
somebody justify me that I will get in trouble if I continue to use MS
Access in this multi connection situation. What other databases like Sybase
iAnywhere, MS Sql server Express edition, MSDE to be considered for the MS
Access replacement.

It will be nice if I get the comparision list somewhere...

We dont want to spend more amount on databases like SQL Server, Oracle,
Sybase, also we have minimal expertise who should be able to manage the
databases.

Thanks

 

[AlanM]

Access can cope with 4 consecutive users, considering that it takes a
fraction of a second normally to make a request from the DB, that is heaps,
the 5th user would still get his request but he may have to wait a fraction
of a second.

But all the same I would use MSDE it s free and powerful

 

[Bob Barrows [MVP]]

Access can cope with 4 consecutive users,

LOL
4? Where did you get this number?
Try making this claim in an Access newsgroup and see what response you get.

considering that it takes a
fraction of a second normally to make a request from the DB, that is
heaps, the 5th user would still get his request but he may have to
wait a fraction of a second.

But all the same I would use MSDE it s free and powerful

No argument. It is HARD to write an application that handles that many users
using Access on the backend. Possible, but hard. You have to do everything
correctly - no room for error at all.

The only issue with MSDE is that it is intended to be used as a development
platform and threfore has built-in throttling to slow down the response when
too many concurrent threads are running (the exact number that initiates the
throttling is hotly debated. I've seen claims of anywhere from 5 to 10.
There are factors that can affect this number)

A better answer is to wait a couple weeks and get SQL 2005 Express. it's
free, and has no throttling restriction.

 

[middletree]

A better answer is to wait a couple weeks and get SQL 2005 Express. it's

free, and has no throttling restriction.

Do you happen to know how many concurrent (not consecutive ) connections
the new SQL Svr Express will allow?

 

[AlanM]

LOL
4? Where did you get this number?

this news group some time ago

Try making this claim in an Access newsgroup and see what response you
get.

according to this article it is 10

http://www.aspfaq.com/show.asp?id=2195

No argument. It is HARD to write an application that handles that many
users using Access on the backend. Possible, but hard. You have to do
everything correctly - no room for error at all.

The only issue with MSDE is that it is intended to be used as a
development platform and threfore has built-in throttling to slow down the
response when too many concurrent threads are running (the exact number
that initiates the throttling is hotly debated. I've seen claims of
anywhere from 5 to 10. There are factors that can affect this number)

A better answer is to wait a couple weeks and get SQL 2005 Express. it's
free, and has no throttling restriction.

very interesting

 

[Bob Barrows [MVP]]

this news group some time ago



according to this article it is 10

http://www.aspfaq.com/show.asp?id=2195

Again. Try making that claim in an Access newsgroup and see the reaction.

Aaron has provided a great resource in aspfaq, and I frequently cite
articles at that site. But I do not totally agree with his bias against
Access.

The "10 user" limit is just a number somebody came up with. There is
absolutely nothing to back up that claim besides a mention in an article
(http://support.microsoft.com/default.aspx/kb/154869) on the MS website, an
article that applies to obsolete versions of Jet. Nowhere will you find
stress test results that back up this figure.

It is certainly possible to create a Jet-backend application that handles
hundreds of users. Of course, it is much more difficult to do than it is
with a server-based dbrms such as SQL Server. There is absolutely no room
for error. Everything must be done exactly right, with the goal of
minimizing the time that a particular user/thread stays connected to the
database.

That said, my preference is to use SQL Server if given the choice: stored
procedures and other performance-enhancing features more than make up for
the loss of the TRANSFORM...PIVOT crosstab functionality in JetSQL.

Bob Barrows

 

[MyndPhlyp]

this news group some time ago



according to this article it is 10

http://www.aspfaq.com/show.asp?id=2195

I am by no means an expert on the subject but I think that limitation of 10
refers to the 16-bit Jet database engine rather than Access. The ASP FAQ you
referenced in turn referenced an MS KB article:

http://support.microsoft.com/default.aspx/kb/154869

 

[Chris Hohmann]

Again. Try making that claim in an Access newsgroup and see the reaction.

Aaron has provided a great resource in aspfaq, and I frequently cite
articles at that site. But I do not totally agree with his bias against
Access.

The "10 user" limit is just a number somebody came up with. There is
absolutely nothing to back up that claim besides a mention in an article
(http://support.microsoft.com/default.aspx/kb/154869) on the MS website,
an article that applies to obsolete versions of Jet. Nowhere will you find
stress test results that back up this figure.

[snip]

Actually the "10 user" limit Aaron refers to comes from this article:

http://msdn.microsoft.com/library/en-us/dnmsde/html/msdeforvs.asp

"Jet can support up to 255 concurrent users, but performance of the
file-based architecture can prevent its use for many concurrent users. In
general, it is best to use Jet for 10 or fewer concurrent users."

The article applies to Jet version 4.0.

 

[Bob Barrows [MVP]]

[snip]

Actually the "10 user" limit Aaron refers to comes from this article:

http://msdn.microsoft.com/library/en-us/dnmsde/html/msdeforvs.asp

"Jet can support up to 255 concurrent users, but performance of the
file-based architecture can prevent its use for many concurrent
users. In general, it is best to use Jet for 10 or fewer concurrent
users."

The article applies to Jet version 4.0.

Again, nowhere do they back it up with benchmarks, test results, etc. It
looks like they've just repeated the number from the earlier article.

I used to repeat this party-line myself, until I got soundly slapped down
and re-educated in one of the Access lists to which I used to subscribe.

Yes, I recognize that the file-based architecture can make it difficult to
support many concurrent users. But it's not impossible.

 

[Bob Barrows [MVP]]

Basically, the statement I was attempting to refute, of which I did an
admittedly poor job, was the following:

'The "10 user" limit is just a number somebody came up with. There is
absolutely nothing to back up that claim besides a mention in an
article (http://support.microsoft.com/default.aspx/kb/154869) on the
MS website, an article that applies to obsolete versions of Jet.
Nowhere will you find stress test results that back up this figure.'

There is something to backup the "10 user" limit claim besides the
above article. Namely, this article
(http://msdn.microsoft.com/library/en-us/dnmsde/html/msdeforvs.asp)
on the MS website, an article that applies to Jet 4.0.

Noted.

 

[Chris Hohmann]

[snip]

Actually the "10 user" limit Aaron refers to comes from this article:

http://msdn.microsoft.com/library/en-us/dnmsde/html/msdeforvs.asp

"Jet can support up to 255 concurrent users, but performance of the
file-based architecture can prevent its use for many concurrent
users. In general, it is best to use Jet for 10 or fewer concurrent
users."

The article applies to Jet version 4.0.

Again, nowhere do they back it up with benchmarks, test results, etc. It
looks like they've just repeated the number from the earlier article.

I used to repeat this party-line myself, until I got soundly slapped down
and re-educated in one of the Access lists to which I used to subscribe.

Yes, I recognize that the file-based architecture can make it difficult to
support many concurrent users. But it's not impossible.

--
Microsoft MVP -- ASP/ASP.NET
Please reply to the newsgroup. The email account listed in my From
header is my spam trap, so I don't check it very often. You will get a
quicker response by posting to the newsgroup.

Basically, the statement I was attempting to refute, of which I did an
admittedly poor job, was the following:

'The "10 user" limit is just a number somebody came up with. There is
absolutely nothing to back up that claim besides a mention in an article
(http://support.microsoft.com/default.aspx/kb/154869) on the MS website, an
article that applies to obsolete versions of Jet. Nowhere will you find
stress test results that back up this figure.'

There is something to backup the "10 user" limit claim besides the above
article. Namely, this article
(http://msdn.microsoft.com/library/en-us/dnmsde/html/msdeforvs.asp) on the
MS website, an article that applies to Jet 4.0.

You, Aaron and I are in agreement that the claim itself is poorly supported.
You because you've said so in this thread, I because I am saying so now and
Aaron because he says as much in his article. From his article;

'Microsoft doesn't even publish hard numbers; they just use off-hand
references such as "ten or fewer" and never truly define what they mean by
"high-concurrency."'

 

[Michael D. Kersey]

Again, nowhere do they back it up with benchmarks, test results, etc. It
looks like they've just repeated the number from the earlier article.

I used to repeat this party-line myself, until I got soundly slapped down
and re-educated in one of the Access lists to which I used to subscribe.

Yes, I recognize that the file-based architecture can make it difficult to
support many concurrent users. But it's not impossible.

I concur. It can even be quite easy.

I know of ASP applications with Access databases that support thousands
of users, with hundreds of database requests per hour. Luckily most are
well-designed. The problems encountered in these systems were not with
Access per se but primarily with database structure and indexing. These
systems have been in production several years with no serious throughput
problems.

I should note that these applications are scheduled for migration to SQL
Server and that the migration code review process is more burdensome
because MSDE was not used as the original database instead of Access.

Access is easy to use and tempting. But when one uses Access initially,
a later migration to SQL Server will be more difficult because:
- migration requires switching databases on a live system. And once you
switch over to the new database, there's little chance of reverting to
the old database should problems arise. Instead, any problems must be
fixed quickly and the situation can be exhausting and tense.
- migrating from Access to SQL Server may require changes in the ASP
code. Had MSDE been used initially, the migration would require no
coding changes and would be almost transparent to users. It _is_
possible to write applications in a database-independent manner, but few
apps are written that way.

So I recommend starting with the database you want to finish with. If
that's SQL Server then I'd start with that or MSDE, not with Access.

OTOH if I were selling a software package, I'd opt for an open-source
database such as PostGreSQL, which is full-featured but free.

 

[AlanM]

Again. Try making that claim in an Access newsgroup and see the reaction.

Aaron has provided a great resource in aspfaq, and I frequently cite
articles at that site. But I do not totally agree with his bias against
Access.

The "10 user" limit is just a number somebody came up with. There is
absolutely nothing to back up that claim besides a mention in an article
(http://support.microsoft.com/default.aspx/kb/154869) on the MS website,
an article that applies to obsolete versions of Jet. Nowhere will you find
stress test results that back up this figure.

Fair enough I stand corrected