On 1 May 2018, at 1:45am, Roman Fleysher <roman.fleys...@einstein.yu.edu> wrote:
> If x=10 has less than nX dots, all dots with x=10 are deleted. Because of > deletion, y=3 which previously had more than nY dots no longer passes the > threshold and thus y=3 must be deleted too. This could cause deletion of some > other x, etc. At the end, number of dots on all vertical lines must be more > than nX and number of dots on all horizontal lines must be more than nY. > > Could this be achieved with SQLite? The continual refining of 'survivors' suggest that you need a WITH RECURSIVE construction: <https://sqlite.org/lang_with.html> Index both x and y columns in your table. It may be possible to complete the task purely in SQLite, I wouldn't choose to do it that way but there are people here who delight in crafting complicated Recursive Common Table Expressions. Simon. _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
