Progress
Database Design
Guide


Maintaining Indexes Through the 4GL

As you work with your application, you will want to know when Progress creates and updates indexes. Progress creates a new index entry for a record at the first occurrence of any one of the following:

Progress updates an index at the end of any statement in which it changes the values for one or more index fields. Because Progress updates indexes immediately (at the end of an UPDATE statement), Progress immediately FINDs records in the order of the new index, while the data in the found record is unchanged. Progress changes the data in the record at the end of the scope of the record or when it releases the record.

NOTE: Progress does not update an index if the value you try to assign to the index field is the same as the current value of the index field.

You can change the name of an index at any time. You can also delete nonprimary indexes. However, before letting you delete a primary index, Progress requires that you first designate another index as primary.

If there is only one index, you must create a new index before deleting the existing index. You cannot change any of the component definitions of an index. Instead, you must delete the index and recreate it using the modified component definitions.

Remember that Progress assumes that the first index you create is the primary index, so create your primary index first.


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