sql server - Auto assign column value when row is created -


i using ef6 , sql server 2014.

i have following simplified model:

public class order {     public int id { get; set; }     public datetime created { get; set; }     public ienumerable<orderitem> orderitems { get; set; } } public class orderitem {     public int id { get; set; }     public int orderid { get; set; }     public order order { get; set; }     public string itemname { get; set; }     public int orderitemnumber { get; set; } }

the id properties standard auto-increment primary keys.

the orderitem.orderitemnumber property uniquely identifies orderitem within context of given order.

when new orderitem row inserted needs assigned next orderitemnumber parent order, select coalesce(max(orderitemnumber),0) dbo.orderitems orderid = 2

is there means using ef6/sql server auto-assign orderitemnumber @ point row inserted?

although proved interesting learning experience on ef support triggers (see https://github.com/nickstrupat/entityframework.triggers) decided re-model.

in case question result of incorrect modelling. orderitemnumber property redundant removed it; sequence orderitems created can inferred id value, , there no real requirement allow re-sequencing.


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