Feedback
 
Did this article resolve your question/issue?

   

Your feedback is appreciated.

Please tell us how we can make this article more useful. Please provide us a way to contact you, should we need clarification on the feedback provided or if you need further assistance.

Characters Remaining: 1025

 


Article

What determines the number of entries in the root index block?

« Go Back

Information

 
Article Number000013062
EnvironmentAll Supported Operating Systems
Progress/OpenEdge Versions
Question/Problem Description
What determines the number of entries in the root index block?
How is the root index block changed as new entries are made to the index?
Steps to Reproduce
Clarifying Information
Error Message
Defect/Enhancement Number
Cause
Resolution
Initially the index is empty and only has the root block. As entries are added to the index, they get added to the root block until it becomes full.

Eventually, the root block has to be split and another level added to the index.

When that happens, the root block will get two entries that point to two leaf level blocks below it. Each leaf level block will then have some of the index entries.

As more index entries are added, one of the leaf level blocks will become full and will be split into two leaf level blocks. A new entry will be added to the root block to point to the new leaf level block.

As more entries are added to the index, more leaf level block splits will occur and new entries for them will be added to the root block. Eventually the root block will become full again and it will be split, adding a first interior level into the index.

Now there are three levels: the root block, two interior level blocks, and the leaf level blocks. The root block will once again have only a few entries which point to the two intermediate level blocks.

As more index entries are added, more block splits will occur and eventually the root block will become full again at which point another interior level will be added and the root block will end up with only a few entries.

So as entries are added, the root block goes from almost empty to full and then from full to almost empty.

Workaround
Notes
Attachment 
Last Modified Date9/13/2015 5:23 AM