- What Is the ZODB?
- Relational Database Management Systems (RDBMS)
- Why Are Database Adapters Necessary?
- Which Database Adapter Do I Need?
- Connecting MySQL and Zope
- Gadfly—Zope's Integrated Demo Relational Database
- Introduction to SQL
- Using Z SQL Methods to Submit SQL Statements
What Is the ZODB?
The ZODB (Z Object Database) is a database integrated in Zope. The ZODB's main function is to ensure that the objects created in Zope are persistent and are not deleted after shutting down the Zope process. Therefore, when working in Zope, every object is stored in the ZODB. But not only does the object get stored, its current state, information about it, and how it is used is stored as well, that meaning the user's actions are stored. This allows the user to undo those actions. This means that the ZODB is a transactional, object-oriented, persistence mechanism.
However, the ZODB is no alternative for a relational database. For one thing, it is not possible to send complex SQL queries to the ZODB. Moreover, you may already have a consisting database. If that is the case, you would not want to have to enter all the data again in another database or transfer it in another way. Another argument against using the ZODB instead of a Relational Database Management System (RDBMS) is that the ZODB is not suitable for storing large amounts of data.