V
Van T. Dinh
To answer your question properly. let me divide a database
application into 2 different components:
* The front-end application which handles the user's
interactions and communicating with the second component.
* The back-end component, i.e. the database engine which
handles the definition, storage, retrieval and
manipulation of data.
Access in loose terms is a software that can handle both
components above. The default database engine that comes
with and used in Access is the JET database engine.
However, you can use other database engines such as MSDE,
MS-SQLServer, Oracle, etc ...
The front-end component can handle as many users as you
like since each user runs a separate copy of the front-end
on his/her desktop. Thus, the real question is how many
users can the back-end (JET database engine / MS-SQL
Server, etc ...)
Clearly, proper database servers like MS-SQL Server,
Oracle, SyBase, etc ... can handle a lot more than 25 but
you pay big money for the database server software.
With JET database engine (which is not a database server),
the absolute limit is 255 users. The practical limit
depends on a large number of factorssuch as:
* How well the database is designed & structured.
* How well the front-end is designed to get the data from
the back-end.
* How dynamic the data is.
* Hardware platform / network configuration.
* etc ...
It's hard to say what is the practical limit of the number
of concurrent users. Someone mentioned that he have a
working Access / JET database with over 100 users.
Equally, we have questions why Access / JET does not
perform well evwn with one user.
Personally, I look for an upsize to SQL Server at about 25
users. However, the *primary* reason is how *important*
the database is to the business, NOT because of JET
failure to handle 25 users. For me, if a database is used
by 25 users, it must be important enough (looking at the
pay for 25 people for a day and whether the business can
afford 25 people being non-productive for a day
occasionally). The main thing I look for in upsizing is
the proper back-up and restoration procedure since Access
does not have proper back-up and restoration (besides
copying the mdb files).
HTH
Van T. Dinh
MVP (Access)
application into 2 different components:
* The front-end application which handles the user's
interactions and communicating with the second component.
* The back-end component, i.e. the database engine which
handles the definition, storage, retrieval and
manipulation of data.
Access in loose terms is a software that can handle both
components above. The default database engine that comes
with and used in Access is the JET database engine.
However, you can use other database engines such as MSDE,
MS-SQLServer, Oracle, etc ...
The front-end component can handle as many users as you
like since each user runs a separate copy of the front-end
on his/her desktop. Thus, the real question is how many
users can the back-end (JET database engine / MS-SQL
Server, etc ...)
Clearly, proper database servers like MS-SQL Server,
Oracle, SyBase, etc ... can handle a lot more than 25 but
you pay big money for the database server software.
With JET database engine (which is not a database server),
the absolute limit is 255 users. The practical limit
depends on a large number of factorssuch as:
* How well the database is designed & structured.
* How well the front-end is designed to get the data from
the back-end.
* How dynamic the data is.
* Hardware platform / network configuration.
* etc ...
It's hard to say what is the practical limit of the number
of concurrent users. Someone mentioned that he have a
working Access / JET database with over 100 users.
Equally, we have questions why Access / JET does not
perform well evwn with one user.
Personally, I look for an upsize to SQL Server at about 25
users. However, the *primary* reason is how *important*
the database is to the business, NOT because of JET
failure to handle 25 users. For me, if a database is used
by 25 users, it must be important enough (looking at the
pay for 25 people for a day and whether the business can
afford 25 people being non-productive for a day
occasionally). The main thing I look for in upsizing is
the proper back-up and restoration procedure since Access
does not have proper back-up and restoration (besides
copying the mdb files).
HTH
Van T. Dinh
MVP (Access)