Difference between revisions of "Microsoft Access Backend"
| Line 51: | Line 51: | ||
==== Methods ==== | ==== Methods ==== | ||
| + | |||
===== update ===== | ===== update ===== | ||
| + | The backend object does not automatically reflect changes of the backend database. | ||
| + | |||
| + | The update method updates all objects and checks whether the existing linked objects | ||
| + | are identifyable. | ||
| + | |||
| + | <syntaxhighlight lang="vb"> | ||
| + | updateBackend | ||
| + | 'or | ||
| + | getBackend.update | ||
| + | </syntaxhighlight> | ||
| + | |||
===== relink ===== | ===== relink ===== | ||
| + | Relinking all backend database objects to reflect the current location and environment | ||
| + | can become a tedious task, if many objects are linked. | ||
| + | |||
| + | The relink method checks for each linked object which connection is currently present, | ||
| + | tries to adjust the connection towards the current location and environment and reconnects | ||
| + | the object accordingly. | ||
| + | |||
| + | <syntaxhighlight lang="vb"> | ||
| + | relinkBackend | ||
| + | 'or | ||
| + | getBackend.relink | ||
| + | </syntaxhighlight> | ||
| + | |||
===== amendConnections ===== | ===== amendConnections ===== | ||
| + | Connections | ||
| + | |||
| + | ===== linkTable ===== | ||
| + | |||
| + | |||
| + | ===== refreshOdbcTables ===== | ||
=== Backend Connection === | === Backend Connection === | ||
Revision as of 01:02, 5 August 2012
General
It is good practice to separate a frontend from a backend, ie to put queries, forms, reports and the business logic into a frontend database and all tables into a backend database no matter what kind of database it is.
Architecture
Server
Every backend is a server no matter whether it is a Microsoft Jet or another type of database. Each server has a unique name.
Location
Development does not happen on the same machine all the time. The location is derived from the workstation name.
Environment
There are usually three environments, namely
- Development
- Testing / Pre-Production
- Production
ConnectionType
Databases can be accessed through different types of connections like
- Jet
- ODBC
- OLEDB
Model
Backend
Properties
The backend class has collections for each architectural aspect:
<uml class style="plain" scale="75" direction="lr"> [Backend]1-*>[ConnectionTypes] [Backend]1-*>[Environments] [Backend]1-*>[Locations] [Backend]1-*>[Servers] </uml>
It also knows all known connections as well as its tables and queries:
<uml class style="plain" scale="75" direction="lr"> [Backend]1-*>[Queries] [Backend]1-*>[Tables] [Backend]1-*>[Connections] </uml>
Methods
update
The backend object does not automatically reflect changes of the backend database.
The update method updates all objects and checks whether the existing linked objects are identifyable.
updateBackend
'or
getBackend.update
relink
Relinking all backend database objects to reflect the current location and environment can become a tedious task, if many objects are linked.
The relink method checks for each linked object which connection is currently present, tries to adjust the connection towards the current location and environment and reconnects the object accordingly.
relinkBackend
'or
getBackend.relink
amendConnections
Connections