Dear list, sorry to just come up with another performance question. I build a yet small database with one table. It has about 650.000 rows, 75 columns and has at the moment about 650 Mb. It runs on a Intel Pentium M with 2 GHz. The Laptop runs Suse 10.2 and does basicly nothing but this database. sqlite3 -version is 3.3.8
This is the schema: CREATE TABLE 'data'('nr' INTEGER PRIMARY KEY, 'year' INTEGER, 'month' INTEGER, 'day' INTEGER, 'sec' REAL, 'campId' TEXT, 'flightNr' INTEGER, '1' REAL, ... '71' REAL ); CREATE INDEX sec on data(year,month,day,sec); I experience a big variability of time a query needs: ~database> time sqlite3 data.db 'select "14" from data where campId="polstar98" and "14">-9999;' >/dev/null real 0m3.115s user 0m1.748s sys 0m1.368s ~/database> time sqlite3 data.db 'select "14" from data where campId="polstar98" and "14">-9999;' >/dev/null real 0m3.139s user 0m1.756s sys 0m1.380s ~/database> time sqlite3 data.db 'select "42" from data where campId="stream94" and "14">-9999;' >/dev/null real 0m50.227s user 0m4.692s sys 0m3.028s I've tried it with and without index and at different times. Most of the time such simple queries take about 35 sec. Why is that so and what can be done? I can live with 3 sec of response but not up to one minute and the database is still not complete. Would pytables with hdf5 be an alternative? Knowing that this is probably not the right place to ask... Tips, suggestions, recommendation are gratefuly appreciated! Thanks in advance Hubertus ----------------------------------------------------------------------------- To unsubscribe, send email to [EMAIL PROTECTED] -----------------------------------------------------------------------------