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From Nurullah Akkaya <nurullah_akk...@yahoo.com>
Subject keeping the table ordered
Date Sat, 03 Feb 2007 12:45:25 GMT
i have a table of 100 million records when i do a select i get 600k  
to 1million records table structure is as follows

		stmt.executeUpdate("CREATE TABLE POSTINGLIST ("
				   +"WORDID INTEGER NOT NULL,"
				   +"DOCID INTEGER NOT NULL,"
				   +"ANCHORID INTEGER NOT NULL,"
				   +"DOCPOSITION SMALLINT NOT NULL,"
				   +"FLAG SMALLINT NOT NULL)");
		
		stmt.executeUpdate("CREATE INDEX WORDID ON POSTINGLIST(WORDID)");
		stmt.executeUpdate("CREATE INDEX DOCID ON POSTINGLIST(DOCID)");
		stmt.executeUpdate("CREATE INDEX ANCHORID ON POSTINGLIST(ANCHORID)");

99 percent of the time i select based on the wordId i have  
implemented all the tuning tips in the manual but it stil takes so  
much time disk i/o seems to be the bottleneck( no swap cpu is idle  
during select derby uses index) what i want to do is keep the tables  
sorted by wordId so that i can avoid random reads and do a sequencial  
read. rigth now insert performence is faster than i expected so i can  
trade some write for read is this possible?

derby is running in embedded mode.


Nurullah Akkaya
nurullah.akkaya@blooby.com

Blooby.com
Tel: +1 (256) 270 4091




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