You can create computed columns in your database tables. In the EF model you just annotate the corresponding properties with the DatabaseGenerated
attribute:
[DatabaseGenerated(DatabaseGeneratedOption.Computed)]
public double Summ { get; private set; }
Or with fluent mapping:
modelBuilder.Entity<Income>().Property(t => t.Summ)
.HasDatabaseGeneratedOption(DatabaseGeneratedOption.Computed)
As suggested by Matija Grcic and in a comment, it's a good idea to make the property private set
, because you'd probably never want to set it in application code. Entity Framework has no problems with private setters.
Note: For EF .NET Core you should to use ValueGeneratedOnAddOrUpdate because HasDatabaseGeneratedOption doesnt exists, e.g.:
modelBuilder.Entity<Income>().Property(t => t.Summ)
.ValueGeneratedOnAddOrUpdate()
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