Kbase P141085: What determines the number of entries in the root index block?
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
1/6/2011 |
|
Status: Verified
GOAL:
What determines the number of entries in the root index block?
GOAL:
How is the root index block changed as new entries are made to the index?
FACT(s) (Environment):
All Supported Operating Systems
Progress/OpenEdge Product Family
FIX:
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.