Concept of Key Flexfield and Descriptive Flexfield

Key Flexfield is used to describe unique identifiers that will have a better meaning than using number IDs. e.g a part number a cost centre etc
Desc Flex is used to just capture extra information.
Key Flexfields have qualifiers whereas Desc Flexfields do not.
Desc Flexfields can have context sensitive segments while Key flexfields cannot.

To desing key flex field one must follow the below step....

• Identifying Key flexfields that are required for you Oracle Applications installation
• Designing a Key flexfield structure
• Selecting the appropriate Key flexfield to define
• Defining structure information for the Key flexfield
• Defining segment attributes
• Defining flexfield qualifiers
• Defining segment qualifiers
• Implementing optional features as needed

Lets say we are defining the structure for an Accounting Flexfield. Query for the Flexfield Title “Accounting Flexfield” using the Flexfield Title window will appper. If there are already existing structures for Accounting Flexfields, they would be listed in the Structures window .
Now
Lets say we want to define a new structure for the Accounting Flexfield with the structure code as “NEW_ACCOUNTING_STRUCTURE”. Enter the code name in the Code window and the title as “New Accounting Flexfield Struc” in the Title window. Enter an optional description for the new structure which may include the purpose of the new structure. Save the changes.

There are few check buttons on the form which can be left unchecked/checked.

The Enabled checkbox is checked by default. You can optionally uncheck it. You cannot delete a Key flexfield structure, but you can disable it by unchecking the Enabled checkbox. Next, you may select a Segment Separator other than the default period. Your choices are period, dash, pipe, or any custom character. You must have a segment separator.

Next, you can select whether you want to Cross-Validate Segments. Unchecking this checkbox will disable cross-validation for this Key flexfield structure. You can then identify whether you want to Freeze Rollup Groups. If you mark this checkbox, you will not be able to change the assigned rollup groups in the Define Segment Values form. As a last step, you can determine whether you want to Allow Dynamic Inserts for Key flexfield structures. If you do not allow dynamic inserts, you must create all flexfield combinations in the combination form.