Logical tables exist in the Business Model and Mapping layer.
The logical schema defined in each business model must contain at least two logical tables, and you must define relationships between them.
Each logical table is associated with one or more logical columns and one or more logical table sources. You can add a new logical table source, edit or delete an existing table source, create or change mappings to the table source, or define when to use logical tables sources. See Creating Logical Table Sources.
You can change the logical table name, reorder the logical table sources, and configure the logical keys, both primary and foreign
This section contains the following topics:
Dragging and dropping physical tables from the Physical layer to the Business Model and Mapping layer is the recommended method for creating logical tables. If a table does not exist in your physical schema, you can create the logical table manually.
If you drag and drop physical tables from the Physical layer to the Business Model and Mapping layer, the columns in the table are also to the logical table along with key and foreign key relationships. Logical keys and joins are created that mirror the keys and joins in the Physical layer.
After creating a logical table using the menu option method, you must create all keys and joins manually.
After adding objects to the Business Model and Mapping layer, you can modify the objects in the logical table without affecting the objects in the Physical layer.
If you create new tables or drag additional tables from the Physical layer to the Business Model and Mapping layer, you must create the logical mappings between the new or newly dragged tables and the previously dragged tables.
See Defining Logical Joins with the Joins Manager and Defining Logical Joins with the Business Model Diagram.
A lookup table stores multilingual data corresponding to rows in the base tables. See Localizing Business Intelligence in System Administrator's Guide for Oracle Business Intelligence Enterprise Edition.You can improve the performance of fragmented logical table sources by enabling the data driven fragment selection option in the
Data driven fragment selection is disabled by default.
After creating tables in the Business Model and Mapping layer, you specify a primary key for each dimension table.
Logical dimension tables must have a logical primary key. Logical keys can be composed of one or more logical columns.
Note:
Oracle recommends that you do not specify logical keys for logical fact tables.
Oracle recommends that you do not use foreign key joins in logical tables.
If you must create these joins, you must first enable the Allow logical foreign key join creation option in the Options dialog.
See Creating Logical Foreign Key Joins with the Joins Manager.
The Foreign Keys tab of the Logical Table dialog exists so that you can view logical foreign keys you might have had in a previous release of Oracle Business Intelligence.