Number of Concurrent Users?

[ADezii]

Can someone please tell me the MAXIMUM number of concurrent users that
Access 2003 allows for a Front/Back End architecture? I am placing all data on a departmental server and intend to customize individual Front Ends on what will probably be several hundred Clients. I had heard that the MAXIMUM number of current users is 255 but I must be absolutely sure before I continue developement. (Oracle or SQL Server are not viable options since licensing already exists for Access 2003). Any and all help would be greatly appreciated.

Thanks,
ADezii

[deBassMan]

Access is great for many things - but what it is not optimised for is supporting a substantial number of concurrent users.

My experience is that 10-15 concurrent users is the maximium that Access using Jet can handle comfortably.

If you are even considering supporting around 255 concurrent users forget using Access Jet engine and consider using MySQL as the back-end retaining Access as the front end.

good luck

[PEB]

It's true that when the number of users increase, the problems with Access appear!
But it depends of the charge of the different tables on minute!
You can manage this big number of users using different databases loaded on the Server! One user on his front end can use tables from different databases!

[ADezii]

It's true that when the number of users increase, the problems with Access appear!
But it depends of the charge of the different tables on minute!
You can manage this big number of users using different databases loaded on the Server! One user on his front end can use tables from different databases!

Thanks for your input on this matter - it is greatly appreciated
ADezii

[PEB]

You also have to take care about stopping the work with the database for repair and compact!
When you use Access when there is a logged user in case of failure of the database it's impossible to repair the database! In your front end application its good to place an algoritm to close the front end applications of all users in case of failure!

It's the same thing when you want to modify the structure of your database!

If you expect to have large amount of data, it's good to use run SQL statements to the network database placing the results in the local machines! It's similar like a WEB Php or other programming interface passes the SQL to the database and obtain the result! Here the obtained result is better to be on the Local machines for better performance!

When You use action queries it's better to use as fast as possible queries. This diminues the number of concurrent users - the users who pass in the same time a query to the database!

Using the local machines and temporary tables installed there can diminue the charge of the network database and decrease the number of concurrent users!

You have to consider the limitations of Access:
Max number of tables: 2000
Max volume of a database: 2GB
Max number of Forms and so on!
And the interruption of the work of your colleages when you modify athe databse or only to repair it, it's also significant, but you can optimize this inconvenients by VB code!
It' s also important to think doing archiving of the information! For exemple the information of one year can be placed in one database, for the new year you open a new database, using the same front end!
In this cases you can place in the new database the active information from the past year!
IF there is a large amount of data your periods can be smaller then 1 year!
So this will be your application to collect and treat the information operatively! For strategicaly needs you have to use similar database and append the new records there! The information will be treated slowly with hours and not be available on all the network and for many users!

Have a good chance!

Sincerly Vladimir /PEB/

[ADezii]

Thanks for your many helpful suggestions.
ADezii

[PEB]

Type "Access specifications" in the Help of Access and you'll obtain all the information about the limitations of Access!

[ADezii]

Type "Access specifications" in the Help of Access and you'll obtain all the information about the limitations of Access!

Thanks,
Best hint I got so far. The number of Concurrent Users is what I originally
thought - 255. Thanks again.
ADezii