Greg Stark wrote:
The discussions before talked about a mechanism to try to place new
> tuples as close as possible to the proper index position.
Means this that an index shall have a "fill factor" property, similar to Informix one ?
From the manual:
The FILLFACTOR option takes effect only when you build an index on a table that contains more than 5,000 rows and uses more than 100 table pages, when you create an index on a fragmented table, or when you create a fragmented index on a nonfragmented table. Use the FILLFACTOR option to provide for expansion of an index at a later date or to create compacted indexes. When the index is created, the database server initially fills only that percentage of the nodes specified with the FILLFACTOR value.
# Providing a Low Percentage Value If you provide a low percentage value, such as 50, you allow room for growth in your index. The nodes of the index initially fill to a certain percentage and contain space for inserts. The amount of available space depends on the number of keys in each page as well as the percentage value. For example, with a 50-percent FILLFACTOR value, the page would be half full and could accommodate doubling in size. A low percentage value can result in faster inserts and can be used for indexes that you expect to grow.
# Providing a High Percentage Value If you provide a high percentage value, such as 99, your indexes are compacted, and any new index inserts result in splitting nodes. The maximum density is achieved with 100 percent. With a 100-percent FILLFACTOR value, the index has no room available for growth; any additions to the index result in splitting the nodes. A 99-percent FILLFACTOR value allows room for at least one insertion per node. A high percentage value can result in faster selects and can be used for indexes that you do not expect to grow or for mostly read-only indexes.
Regards Gaetano Mendola
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