This is for those who love a challenge. I am trying to come up with a query that would calculate the Standard Deviation and Variance for 15 fields. Although in theory this is easily done in Access, MySQL does not have the same mathematical calculations that Access/SQL does.
Here is the query as it stands in Access: Select avg(Item01) as Item01a, stdev(Item01) as Item01d, avg(Item02) as Item02a, stdev(Item02) as Item02d, avg(Item03) as Item03a, stdev(Item03) as Item03d, avg(Item04) as Item04a, stdev(Item04) as Item04d, avg(Item05) as Item05a, stdev(Item05) as Item05d, avg(Item06) as Item06a, stdev(Item06) as Item06d, avg(Item07) as Item07a, stdev(Item07) as Item07d, avg(Item08) as Item08a, stdev(Item08) as Item08d, avg(Item09) as Item09a, stdev(Item09) as Item09d, avg(Item10) as Item10a, stdev(Item10) as Item10d, avg(Item11) as Item11a, stdev(Item11) as Item11d, avg(Item12) as Item12a, stdev(Item12) as Item12d, avg(Item13) as Item13a, stdev(Item13) as Item13d, avg(Item14) as Item14a, stdev(Item14) as Item14d, avg(Item15) as Item15a, stdev(Item15) as Item15d, avg(overallscore) as overa, stdev(overallscore) as overd from tblFacultyEvalSurgery This is for an online grading system that, except for 5 pages, has been converted over to MySQL and Linux / Apache. 2 of which have this problem. Avg() is easy, but it's the StDev that I can't get. St Dev is made from Variance (or the mean), which again is not a function of MySQL. To view the Variance and StDev formulae, http://davidmlane.com/hyperstat/A16252.html. If you have any ideas, I will be working on this for the next few days. Thanks! J.R.
