Availability
Databases can be made available
to many users over a network using various methods.
A central database stored on a
file server, can be made available on a multi-user basis, using record and
table locks on databases, so that records can be locked when one user is
updating a record to avoid two users trying to update records at the same
time.
Another method is to hold a
central database on a file server, but instead of every user gaining access
directly to the entire database. Users make requests for the data they wish
to look at and then a subset of the database is returned to the user to look
at or alter locally. It is returned back to the central database. This
method can be quicker on a large network with a large database, as it means
that not every user is accessing the whole database at the same time. SQL
Server is an example of this method. |
