Multi-user database
Spring's multi-user database allows that two or more users to
work safely at the same database simultaneuously. It allows groups of user to be
responsible to database management.
At Spring, Database Engines that allow multi-user operations are: Oracle,
Mysql, and PostgreSql. Database engine DBA is responsible
to create a multi-user database. To access this database, SpringADM must create users
and sets theirs access permissions. See how to create Workgroups and Users at
Workgroup and User Management.
Security problems at a database occurs mainly due data concurrency, when, two or more
users want to read, edit or modify the same data simultaneously. These are the main cases
of data concurrency:
-
Two users reading the same information plan and writing the same output plan:
Both users get read permission and only one recives write permission, while the
other recives a warning canceling his operation.
-
An user tries to read an information plan while other user is updating the same
plan : The user that is trying to read the plan recives a warning
that other user is updating the plan and his read will be canceled.
-
One user tries to overwrite an information plan while other user is reading the
same plan : The user thats trying to overwrite recives a warning
that the plan is being reading, being possible to wait for the end of the reading
or to cancel the operation.
-
An user tries to use vectorial editing while other users executes some operation
at this same plan : The user that tries to edit the plan recives
a warning that other user is saving this plan and his operation is canceled.
-
After some user enters vectorial editing, other user tries to read this plan :
The user that tries to read the infromation plan will recive a warning thar other
user is editing the same plan, but will recive read permission.
-
An user enter vectorial editing and other user tries to execute some operation at the
same plan : The user that tries to realizar the operation recives a
warning that other user is editing the same plan and his operation is canceled.
-
An user saves an realized edition while other user is reading the same plan :
The user that tries to save the plan will recive a warning that the plan is being
read, being able to wait for the end of the reading or cancel the operation.
-
While an user is saving an edit, other users tries to excute some task at the same plan
: The user that tries to execute the operation recives a warning that
other user is saving this plan and his operation is canceled.
-
After an user saving a plan, other user tries to read, edit or save the same plan :
The user that tries to read, edit or write recives a warning that his copy of the
plan is outdated, being necessary to reload the project.
NOTE: Was added to Spring a button that allows reloading the project.
See also: