> What about increasing the size of an existing index entry? Can that be
> done easily when a new row is added?
I'd say it looks pretty much like inserting a new index tuple...Say "value" is the indexed column.
Find first page in the index featuring "value".
1 If there is space on the page, add the tuple id to the list of the corresponding index entry (just like
creating a new index tuple, but uses less space).else look at next page. If next page has an index tuple with the
sameindexed value, goto 1 else insert new page and create an index tuple on it
> I would be worried about the overhead of doing that on compression and
> decompression.
The compression methods mentioned in the article which was passed on the
list seemed pretty fast. From IO-limited, the test database became
CPU-limited (and a lot faster).