.net - Define a foreign key on a CLR type or not define -


what best practice in entity framework:

1.define foreign key on clr type

public class book {     public int authorid{get;set;}     public author author{get;set;} }

2.not define foreign key(only define navigation property)

public class book {     public author author{get;set;} }

my personal preference use define fk , set key value (authorid) when defining relationship.

there's 2 great article here , here julie lerman explain of benefits of taking approach.

here's summary:

save grief , use foreign key

rather setting navigation property , having worry state of [related entity], set [id] property, because have access value in [related entity] instance. find myself suggesting developers. on twitter, see question: “why ef inserting data exists?” , guess correctly in reply: “any chance u r setting navigation property on new entity instead of fk? j”


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