Generate a composite unique constraint/index, in EF Core

EF Core 1.1 generating unique index on FK one-to-one

I'm using EF Core 1.1 and created my one-to-one relationships, an example:...EntityTypeBuilder<Account> .HasOne(a => a.Customer) .WithOne(a => a.Account) .HasForeignKey<Account>(a => a.CustomerId) ...Now using Add-Migration on my DbContext it generates the following:...migrationBuilder.CreateIndex( name: "IX_Accounts_CustomerId", tab...

EF Core / Sqlite one-to-many relationship failing on Unique Index Constraint

The context is each ...Car... has a corresponding ...CarBrand.... Now my classes are as shown below:...public class Car { public int CarId { get; set; } public int CarBrandId { get; set; } public CarBrand CarBrand { get; set; } } public class CarBrand { public int CarBrandId { get; set; } public string Name { get; set; } } pub...

Does EF Core allow a filtered/partial unique index which does not allow multiple NULLs?

EF Core allows... a unique (filtered) index to contain multiple NULLs....Can I configure it to ...not allow... multiple NULLs?...Suppose I've defined a unique index over properties ...Column1..., ...Column2..., ...Column3...:...config.Entity<Product>() .HasIndex("Column1", "Column2", "Column3") .IsUnique(); ...An example:...Id Column1 C...

Is there a data annotation for unique constraint in EF Core (code first)?

I've written an Attribute class that can allow you to decorate your EF Core Entity class properties to cause a Unique Key to be generated (without the Fluent API)....using System; using System.ComponentModel.DataAnnotations; /// <summary> /// Used on an EntityFramework Entity class to mark a property to be used as a Unique Key /// </summary> [Attr...

Generate a composite unique constraint/index with owned entity, in EF Core

I have an entity that owns another entity...public class Entity1 { [Key] [DatabaseGenerated(DatabaseGeneratedOption.Identity)] public virtual int ID { get; set; } public string Property { get; set; } public Entity2 Description { get; set; } } public class Entity2 { public string Test { get; set; } } ...and I need to create an index ...

EF Core Fluent API - unique constraint not being detected/included in migration

I am trying to add a unique constraint on two columns. I found multiple sources declaring that I should be using HasAlternateKey method for EF Core Fluent API applications. However, after running Add-Migration, the code that is generated in the migration files does not include the constraint - almost as if its being purposely ignored or not detec...

EF Core SQLITE - SQLite Error 19: 'UNIQUE constraint failed

Ok, i solved problems. Read some articles about EF DbContext. When i have used two other context's for GET User and CREATE message, the entities (user1 and user2) were not the same entities which i have used for second context. I mean, the entiies were this same, but they had another tracking...EF Core / Sqlite one-to-many relationship failing on U...

EF Core - error with duplicated key while adding data with unique index

Thanks to @Zer0's and @Steve Py's suggestions I came up with the following solution:...void Insert(IEnumerable<Transaction> data) { using(var context = dbContextFactory.CreateDbContext(new string[0])) { List<Stock> stocks = data.Select(s => s.RelatedStock).Distinct(new StockComparer()).ToList(); ...

Setting a column unique null without being an index in .NET EF Core

I would like to add a field to a table that should be unique, but is not required (so it can be null) and it is not an index. This is doable with SQL, something like this in mysql:...CREATE TABLE MyTable ( ... field VARCHAR(255) UNIQUE ... ) ...I tried overriding ...DbContext.OnModelCreating... and adding these:...protected override void OnMo...

CREATE UNIQUE INDEX duplicate key when I update-database by EF Core

The unique index is generated by EF Core because you have configured one-to-one relatiosnhip between ...City... and ...Country...:...builder.HasOne<Country>(x => x.Country) .WithOne(x => x.City) .HasForeignKey<City>(x => x.CountryId); ...Apparently this is not what the data demands - this should be one-to-many relationship instead (..