Terms used to describe different ways to model inheritance in database


 

i'm learning how model inheritance in database , have came across terms believe synonyms.  hope can confirm understanding:

 

table per class = table per type (tpt) = table per subclass

table per abstract class = table per hierarchy (tph)

 

thanks.

 

your correct in thinking table per class/subclass synonomous table per type.

 

however, table per hierarchy means putting data subclasses in 1 table.  example, if customeraddress inherits address address table have addresstype column.

 

this blog describes strategies modelling class hierarchies you're interested in (although example naive);

 

http://blogs.microsoft.co.il/blogs/bursteg/archive/2007/09/30/how-to-model-inheritance-in-databases.aspx



Architecture  >  Architecture General



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