entity framework - What's the proper way to model this relationship in ERD and EF? -

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i'm designing brand new db model new system. goal have stored in sql , mapped objects entity framework. i'm heavily using table-per-hierarchy pattern in order support complex object hierarchy , have inforced "properly" db engine.

i have following situation not sure how handle:

i have set of entities called resources. each resource specific type , contains number of specific attributes.

  • resource (abstract class, maps resources table)
  • resource table has discriminator column , resourceid primary key
  • classes such as: serverresource (concrete class, inherits resource, maps urlresources table that's 1-1 resource... overall there dozehn other resources-types (number growing)
  • each type of resource has set of unique properties specific resource)

i have number of entities called checks. each resource contains number of checks. resourceid foreign key in checks table. checks more interesting. there check types common or types of resources. , there check types specific types of resources. more precise:

  • check (abstract class, maps checks table, checkid primary key)
  • outagecheck (is supported types of resources)
  • sslcertexpirationcheck (is supported 1 type of resource)
  • etc. there approximately 3-4 types of checks per resource type. 1-2 of shared across resources, while rest custom specific resource

so, question how map checks both in erd entity framework. straight-forward approach create few dozen tables, each specific combo of resource type , check type. ie: serveroutagecheck, storageoutagecheck, urloutagecheck, urlsslexpiraitoncheck, serverlowmemorycheck, etc.

this seems little hard manage , maintain. love able share common checks within single table, specific common check (ie: outagecheck) , deviate on checks resource specific (ie: sslexpirationcheck). possible? or o^2 best can table-management perspective?

last thoughts. database frequenty read , infrequently written to. able cache heck out of reads, if necessary.

i'm going refer 3 tags, , advise pay particular attention info tab in each.

single table inheritance have tagged . info tab discusses joys , woes associated having lots of nulls in single simple table.

class table inheritance alternative, 1 puts attributes pertain subclasses in tables attribute has meaning.

shared primary key design technique lets enforce one-to-one nature of subclass/superclass relationship, , gives handy way of joining specialized data generalized data.

most of have merely repeat what's in info tabs in 3 tags. may find associated questions , answers relevant case well.


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