I have a table, 'voting,' with 31 columns. For each of 28 REAL columns I need to calculate averages both by groups and total. I tried:
sqlite> select AVG(pos) from voting where cat = 'eco'; and 0.0 was returned. Before this I tried combinations that were syntactically incorrect; e.g., sqlite> select AVG(*) from voting where cat = 'eco' order by 'pos'; SQL error: wrong number of arguments to function AVG() sqlite> select AVG() from voting where cat = 'eco' order by 'pos'; SQL error: wrong number of arguments to function AVG() The Definitive Guide does not have much on aggregate functions. I also could not find any information on aggregates on the web site. What I need to do with the data from table 'voting' is (in Python using psqlite2) is to calculate the average of each of 28 numeric columns for each of the three 'pos' column values within each of the three 'cat' column values. These will be saved to lists; for example, c1p1[...], c1p2[...], c1p3[...] ... c3p3[...]. Then I can iterate through those lists and calculate the averages of averages, i.e, c1, c2, c3. However, I'm stuck on the proper SQL syntax. A nudge in the right direction -- including pointers to the appropriate documentation -- would be much appreciated. Rich -- Richard B. Shepard, Ph.D. | The Environmental Permitting Applied Ecosystem Services, Inc. | Accelerator(TM) <http://www.appl-ecosys.com> Voice: 503-667-4517 Fax: 503-667-8863 ----------------------------------------------------------------------------- To unsubscribe, send email to [EMAIL PROTECTED] -----------------------------------------------------------------------------
