what to do when relation table are increasing more than 60-70 in m:n relationship

Question

My problem is as follows

I have MainEntity table which is related to SubEntiyTable1,SubEntityTable2 ....and so by m:n relationship .I have such 30 different SubEntity and around 10 mainEntity table, each MainEnityTable1,MainEnityTable2,MainEnityTable3 ...and SubEntity2,SubEntity 2..have different parameter so I can not maintain it all in same table so I am keeping different table for each enity.Now I want make relation table between them but atleast 60 relation tables will be created .Is it feasable solution ??

score 0 · Accepted Answer · edited May 23 '17 at 12:04

Unless you want to forbid some main entity / sub entity combinations, you can do it with just one relationship (aka. junction or link) table, by using inheritance¹:

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¹ More precisely: "all classes in the same table" or "class per table", but not "concrete class per table". For more in inheritance (aka. category, subtyping, subclassing, generalization hierarchy etc.), search for "Subtype Relationships" in ERwin Methods Guide. For some hints on the physical implementation of the inheritance in the relational database, including what the terms above mean, see this post, this post and this post.

Thanks Branko,Srry for late reply ,I will work out on this solution — Amit Deshmukh, May 12 '13 at 06:41

what to do when relation table are increasing more than 60-70 in m:n relationship

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