Every OpenWGA Content Store of version 5 owns a unique universal ID, called UUID. The UUID is automatically generated on first connect of every OpenWGA Content Store to OpenWGA and stored on the database backend (as extension data field on the database).
The UUID differs from database keys in that it actually references the backend database. If you connect the same backend database multiple times under differing database keys from different OpenWGA servers it will always return the UUID.
The UUID is an RFC4122 compliant ID and looks like this example:
OpenWGA itself uses the UUID to:
- Bind stored WebTML portlet items to their applications. Changing the UUID may result in all stored portlet items being lost.
The UUID and Content Synchronisation, Migration and Dumps
The UUID denotes an independent data set. The behaviour of UUID when synchronizing, migrating or dumping Content Stores is aligned to this fact:
- Migrating a Content Store into a different database via Content Store Migration (Enterprise Feature) will migrate the UUID with it. Migration source and target will have the same UUID.
- Synchronizing a Content Store into a different database via Content Store Synchronisation will NOT migrate the UUID. The synchronisation target only contains a subset of the original data and may additionally be composed by the synchronized data of multiple sources.
- Dumping a Content Store into a Content Store Dump and loading it into a different database will NOT migrate the UUID. Content Store Dumps are prominently a way to define initial data sets for new Content Stores. However after that initialisation the new database will be independent.
The UUID in WebTML
Where in WebTML a database is adressed by database key one can also use the UUID for adressation by using it prefixed with a hash sign. For example:
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