The database meta-schema file
The .4dbx file is the database meta-schema file for generated applications.
The database meta-schema (.4dbx) file contains the information about the tables, columns, and relations of the relational database that is needed by your application. It is used to create items in your Business Application diagram (4ba).
The database meta-schema file handles CRUD operations for the generated application. For each table with a primary key in the database schema, the application generator creates its database CRUD operations (INSERT, SELECT, UPDATE, and DELETE database statements respectively).
You must have access set up for the database that the application will use.
Constraints management
- uniqueness check for its primary key (only if a primary key exists)
- uniqueness check for each unique constraint (only if a primary key exists)
- for one column, the not null constraint is checked
- foreign key existence is checked
SERIAL management
Primary keys you define as SERIAL
are managed by
the BAM using a table named seqreg
in the meta-schema
(4dbx). BAM uses this table to provide a sequence of
unique integer numbers for SERIAL
columns keys.