2. More About the Object Relational Model
* Type Tables
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Using Type Tables
Type Tables are two column tables (id and name) which are essentially built into an enumerated type by Qcodo. So while only some database vendors (e.g. MySQL) offers support for a formal ENUM column type, Qcodo provides support for the enumerated column types for all database vendors through the use of Type Tables.

Similar to Association Tables, the code generator will look for a user-defined suffix (the default is "_type") to mark certain tables as Type Tables. Type Tables can only have 2 columns, a primary key ID and a unique name.

A Type object will be generated from the table, but note that this Type object will not have the CRUD functionality generated for it. Instead, constants will be defined, one for each row in the Type Table.

Because this is supposed to be an enumerated data type of some kind, the idea is that rows should not be added by the application, but instead, added by developers. So whenever a new enumerated value needs to be added to this Type object, you should manually do the SQL INSERT into this Type Table, and then re-code generate.

In our example below, we show the contents of ProjectStatusType. Note how the Project class has a relationship with ProjectStatusType, and how we can display a Project object's status using the static methods of ProjectStatusType.

List All the Project Status Types (Name and Token Value)

Open - Open
Cancelled - Cancelled (This means that the project would be cancelled)
Completed - Completed

Load a Project Object and View Its Project Status

Project ID: 3
Project Name: Blueman Industrial Site Architecture
Project Status: Open