On Mar 27, 2012, at 9:02 PM, Simon wrote: > I would love to do an sql query that would look like the following ones. > I wonder if they are possible and valid applications for SQL and what would > be the proper implementation for these.
Generally speaking, analytical functions (aka windowing functions [1]) would appear to be the most useful for your endeavor. Sadly, SQLite doesn't provide anything like this out-of-the-box. > I think creating a module ... may be an idea… You can always create you own (aggregate) functions: http://www.sqlite.org/c3ref/create_function.html Here is some inspiration: SQL for Analysis and Reporting http://docs.oracle.com/cd/B28359_01/server.111/b28313/analysis.htm And here are examples of custom functions, including stdev, variance, mode, median, lower_quartile, upper_quartile, etc: http://www.sqlite.org/contrib/download/extension-functions.c?get=25 [1] http://en.wikipedia.org/wiki/Window_function_(SQL)#Window_function _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
