SEO
vBulletin Search Engine Optimization
| |||||||
| Register | FAQ | Members List | Calendar | Search | Today's Posts | Mark Forums Read |
04-12-2008, 03:11 AM
| ||||
| ||||
 Table clustering idea There is a well known command called CLUSTER which organizes table in specified index's order. It has a drawback, that new tuples added are not in this order. Last night I had idea which could be interesting, I hope. The idea is to make use of 'histogram_bounds' collected statistical data. Instead of inserting row into first suitable spot in a table, a table would be "divided" into sections, one for each of histogram_bounds ranges. When inserting, the database would try to find most suitable section to insert (using the histogram_bounds), and if there were free spots there, would insert there. If not, it would either look for a tuple in nearby sections, or first suitable place. What would it do? It would try to keep table somewhat organized, keeping rows of similar values close together (within SET STATISTICS resolution, so a common scenario would be 50 or 100 "sections"). It would make it a bit hard for a table to shrink (since new rows would be added throughout the table, not at the beginning). Other idea than using histogram_bounds would be using the position of key inside the index to determine the "ideal" place of row inside the table and find the closest free spot there. This would be of course much more precise and wouldn't rely on statistic. Regards, Dawid      |
Linear Mode
