Enablers: SQL Database
Functional Description
An SQL database is provided for use by all applications.
Qt Extended applications use the database for PIM data, Categories, and the Document Management system. Using an SQL database improves performance and flexibility of classes requiring permanent storage.
To integrate an alternative database engine, tasks include:
- Providing a Qt SQL Driver (many already supported - see Qt documentation)
- Creating schema and queries to compensate for any peculiarities of the database engine, if any.
Where an SQL database is used for storage in Qt Extended, non-SQL based APIs are provided for application development. This avoids database implementation dependencies and provides faster development for commonly accessed data.
Features
The following facilities are available for migrating to newer versions on a database schema update:
- a version table that records all the release versions ever installed on the device
- a script that runs at start-up, and is implemented in ensureSchema(), that looks at the version table and updates the database (finally adding a row to the version table)
- policy documents defining:
- rules for third parties
- rules for internal (ie TT developers)
- Qt Extended ships with the SQLite database engine. It is also possible to integrate other database engines.
| Copyright © 2009 Trolltech |
Trademarks |
Qt Extended 4.4.3 |
