Dave, Views are good. They make a good way to conceal the way in which SQL can quickly get very hairy when all kinds of relationships exist between multiple entities ina properly normalised database. In fact it's the head-f***ing nature of SQL that makes people shy away from complex realtionships like many-to-many via a 'xref' table in the middle. But in years of database programming I have never hit a situation where compromises should be made which restrict proper normalisation to make data queries more easy to write and understand.
In all cases the data is what is important, and avoiding duplication of any atom of data is crucial. That way, data cleansing issues are more rare and doing it when it's necessary is far easier. Mike PS. I hope top-posting doesn't upset anybody, but it's easier than bottom-posting when you use a screen-reader. On 07/07/2014 19:46, Dave Morriss wrote: > On 07/07/14 19:20, Mike Ray wrote: >> Hello list. >> >> I am sending this to the list as an easier way to include Dave and Ken >> and because it might amuse others. >> >> I haven't been party to the 'discussions' between Dave and Ken about >> database strategies other than some remarks in past community news >> 'casts in which Ken mentioned many-to-many relationships. >> >> I have to say I think from Ken's remarks in the latest community news >> 'cast that Dave is probably right and Ken's description of >> comma-seperated fields in tables sound like enough to make Mr Codd spin >> in his grave. >> >> With this in mind I am going to turn the email I sent to Ken into a >> podcast. I will use SQLite as an RDBMS as it's the world's most used >> system of that ilk, and the easiest to set up and run. I'll also use >> Perl to automate some of the table definitions, data insertion and >> extraction etc. >> >> It sounds like I might have to split it into more than one show, the >> first to define some stuff and explain about SQLite, subsequent show(s) >> to talk about many-to-many, entity relationship diagrams etc. >> >> Now I have to go and have a lie down after hearing mention of >> comma-seperated data in table columns, yuck. >> >> Mike Ray > Mike, > > That sounds very cool. > > Good to have you on the "Dave Team" :-) > > Seriously though, I was suggesting to Ken that we hide the JOIN queries > that this type of redesign will require behind some views, partly to > simplify the PHP that's being used. I'd be interested in other > suggestions of course. > > Looking forward to your show(s). > > Dave > > > _______________________________________________ > Hpr mailing list > [email protected] > http://hackerpublicradio.org/mailman/listinfo/hpr_hackerpublicradio.org -- Michael A. Ray Analyst/Programmer Witley, Surrey, South-east UK The box said: 'install Windows XP, 7 or better'. So I installed Linux Interested in accessibility on the Raspberry Pi? Visit: http://www.raspberryvi.org/ >From where you can join our mailing list for visually-impaired Pi hackers _______________________________________________ Hpr mailing list [email protected] http://hackerpublicradio.org/mailman/listinfo/hpr_hackerpublicradio.org
