Alternative to "master" and "slave" in entity relationship?
there appear to be 3 competing industry alternatives to master/slave. they are:
- Master/Follower
- Parent/Child
- Primary/Secondary
I think primary/secondary is weird because we could have multiple secondary. I feel like after secondary would be tertiary, quaternary, etc. Too much of a pain.
Master/Follower still has vague slavery/feudalism connotations.
That leaves us just with Parent/Child... but I don't really like that because Child sounds incapable, but there are some cases where we'll depend on the Child, not the Parent....
SO, I'm going to suggest yet another combo here:
- Primary/Alternate
That naming should avoid any slavery, gender, and plurality issues.
the industry standard nowadays seems to be {master-follower}
see the following references:
[01]
www.mchotline.com/Reference/MN20B302.pdf
[02]
www.ab.com/linked/drives/drvappsw/files/AppSets_PF700S/AS_PF700S_VirtEncdr_PositMaster_SL.pdf
[03]
www05.abb.com/global/scot/scot201.nsf/veritydisplay/bd987cd590c931fcc1257249003d8f4f/$file/factfile_master_follower_pd11_lowres.pdf
[04] www05.abb.com/global/scot/scot201.nsf/veritydisplay/a11e30d538ab1b49c2256def00493279/$file/en_800stdprg_mfguide_a.pdf
[05] www.danfoss.com/BusinessAreas/DrivesSolutions/MUSEC/
[06] forums.ni.com/t5/Motion-Control-and-Motor-Drives/Converting-a-master-follower-type-Cam-Grinding-Machine-to-CNC/td-p/1469070
[07] www.burhansresearch.com/mrcwfdbk1.htm
[08] www.eurekamagazine.co.uk/article/28893/Master-follower-communication-in-ABB-industrial-drives.aspx
[09] www.lockmasters.com/index.asp?PageAction=VIEWPROD&ProdID=49879
[10] www.perfusion.com/cgi-bin/forum/forum_posts.asp?TID=500
this also makes more sense - no need to employ a morally reprehensible term for a hierachical computer/technological controls arrangement... for example, we would designate connectors as "male" and "female", not "male" and "whore".... both cases "make the point" in a somewhat descriptive sense, however it is best to make the point using non morally reprehensible or inflammatory terms
excellent question, btw!
How about student_id and friend_id? There's no rule that says your foreign keys need to have the same column names as the primary key.
Parent and Child or Owner and Child is the generally accepted solutions.