On 3 Sep 2014, at 8:21pm, John McKown <john.archie.mck...@gmail.com> wrote:
> Those are _both_ nice features. I don't know for sure, but somehow it > seems that virtual columns would be easier to implement. I'm used to calling them 'computed columns' but yes, they should be relatively easy to implement, as long as users accept a bunch of restructions on what they can refer to, roughly equivalent to the restrictions on what can be used in CHECK constraints. I had hoped for them in SQLite4. One alternative is to use VIEWs but, as has already been said in this thread, one can't index a VIEW. And another alternative is to use TRIGGERs and that works fine, but it's bulky and annoying to implement. The MERGE command would, I'm guessing, be far harder to implement because it does such different things depending on what data exists in the tables. Not only would writing the code be difficult but also thinking up the numerous tricky things that would need to go into the test suite. Simon. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
