HasAlternateKey Allows Duplicate Entries

I have the following defined in my DbContext

protected override void OnModelCreating(ModelBuilder builder)

{

    builder.Entity<Order>().HasAlternateKey(o => o.OrderNumber);



    base.OnModelCreating(builder);

}

But when I insert a few orders, each time using this same code:

var order = new Order()

{

    OrderNumber = "12345",

    OrderParts = new List<OrderPartQuantity>()

    {

        new OrderPartQuantity()

        {

            Part = _context.Parts.FirstOrDefault(p => p.BellNumber == "100123"),

            Quantity = 10

        }

    }

};



_context.Orders.Add(Order);

_context.SaveChanges();

The order is inserted each time, even though they all have the same OrderNumber value.

Have I understood this incorrectly, or am I missing something? I'm struggling to find an explanation for this

edited Nov 15 '18 at 17:14

asked Nov 15 '18 at 16:55

Bassie

3,9422051

add a comment |

I have the following defined in my DbContext

protected override void OnModelCreating(ModelBuilder builder)

{

    builder.Entity<Order>().HasAlternateKey(o => o.OrderNumber);



    base.OnModelCreating(builder);

}

But when I insert a few orders, each time using this same code:

var order = new Order()

{

    OrderNumber = "12345",

    OrderParts = new List<OrderPartQuantity>()

    {

        new OrderPartQuantity()

        {

            Part = _context.Parts.FirstOrDefault(p => p.BellNumber == "100123"),

            Quantity = 10

        }

    }

};



_context.Orders.Add(Order);

_context.SaveChanges();

The order is inserted each time, even though they all have the same OrderNumber value.

Have I understood this incorrectly, or am I missing something? I'm struggling to find an explanation for this

edited Nov 15 '18 at 17:14

asked Nov 15 '18 at 16:55

Bassie

3,9422051

add a comment |

I have the following defined in my DbContext

protected override void OnModelCreating(ModelBuilder builder)

{

    builder.Entity<Order>().HasAlternateKey(o => o.OrderNumber);



    base.OnModelCreating(builder);

}

But when I insert a few orders, each time using this same code:

var order = new Order()

{

    OrderNumber = "12345",

    OrderParts = new List<OrderPartQuantity>()

    {

        new OrderPartQuantity()

        {

            Part = _context.Parts.FirstOrDefault(p => p.BellNumber == "100123"),

            Quantity = 10

        }

    }

};



_context.Orders.Add(Order);

_context.SaveChanges();

The order is inserted each time, even though they all have the same OrderNumber value.

Have I understood this incorrectly, or am I missing something? I'm struggling to find an explanation for this

edited Nov 15 '18 at 17:14

asked Nov 15 '18 at 16:55

Bassie

3,9422051

I have the following defined in my DbContext

protected override void OnModelCreating(ModelBuilder builder)

{

    builder.Entity<Order>().HasAlternateKey(o => o.OrderNumber);



    base.OnModelCreating(builder);

}

But when I insert a few orders, each time using this same code:

var order = new Order()

{

    OrderNumber = "12345",

    OrderParts = new List<OrderPartQuantity>()

    {

        new OrderPartQuantity()

        {

            Part = _context.Parts.FirstOrDefault(p => p.BellNumber == "100123"),

            Quantity = 10

        }

    }

};



_context.Orders.Add(Order);

_context.SaveChanges();

The order is inserted each time, even though they all have the same OrderNumber value.

Have I understood this incorrectly, or am I missing something? I'm struggling to find an explanation for this

c# asp.net-core entity-framework-core

edited Nov 15 '18 at 17:14

asked Nov 15 '18 at 16:55

Bassie

3,9422051

edited Nov 15 '18 at 17:14

asked Nov 15 '18 at 16:55

Bassie

3,9422051

edited Nov 15 '18 at 17:14

asked Nov 15 '18 at 16:55

Bassie

3,9422051

asked Nov 15 '18 at 16:55

Bassie

3,9422051

asked Nov 15 '18 at 16:55

Bassie

3,9422051

add a comment |

1 Answer
1

active

oldest

votes

So it seems that calling HasAlternateKey in OnModelBuilding actually requires a new db migration before it is applied.

After calling

Add-Migration TestHasAlternateKeys

This migration was created

public partial class HasAlternateKeyTest : Migration

{

    protected override void Up(MigrationBuilder migrationBuilder)

    {

        migrationBuilder.AlterColumn<string>(

            name: "OrderNumber",

            table: "Orders",

            nullable: false,

            oldClrType: typeof(string),

            oldNullable: true);



        migrationBuilder.AddUniqueConstraint(

            name: "AK_Orders_OrderNumber",

            table: "Orders",

            column: "OrderNumber");

    }



    protected override void Down(MigrationBuilder migrationBuilder)

    {

        migrationBuilder.DropUniqueConstraint(

            name: "AK_Orders_OrderNumber",

            table: "Orders");



        migrationBuilder.AlterColumn<string>(

            name: "OrderNumber",

            table: "Orders",

            nullable: true,

            oldClrType: typeof(string));

    }

}

Now, after calling

Update-Database

I can no longer to duplicate that column

answered Nov 15 '18 at 18:10

Bassie

3,9422051

add a comment |

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1 Answer
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active

oldest

votes

1 Answer
1

active

oldest

votes

So it seems that calling HasAlternateKey in OnModelBuilding actually requires a new db migration before it is applied.

After calling

Add-Migration TestHasAlternateKeys

This migration was created

public partial class HasAlternateKeyTest : Migration

{

    protected override void Up(MigrationBuilder migrationBuilder)

    {

        migrationBuilder.AlterColumn<string>(

            name: "OrderNumber",

            table: "Orders",

            nullable: false,

            oldClrType: typeof(string),

            oldNullable: true);



        migrationBuilder.AddUniqueConstraint(

            name: "AK_Orders_OrderNumber",

            table: "Orders",

            column: "OrderNumber");

    }



    protected override void Down(MigrationBuilder migrationBuilder)

    {

        migrationBuilder.DropUniqueConstraint(

            name: "AK_Orders_OrderNumber",

            table: "Orders");



        migrationBuilder.AlterColumn<string>(

            name: "OrderNumber",

            table: "Orders",

            nullable: true,

            oldClrType: typeof(string));

    }

}

Now, after calling

Update-Database

I can no longer to duplicate that column

answered Nov 15 '18 at 18:10

Bassie

3,9422051

add a comment |

So it seems that calling HasAlternateKey in OnModelBuilding actually requires a new db migration before it is applied.

After calling

Add-Migration TestHasAlternateKeys

This migration was created

public partial class HasAlternateKeyTest : Migration

{

    protected override void Up(MigrationBuilder migrationBuilder)

    {

        migrationBuilder.AlterColumn<string>(

            name: "OrderNumber",

            table: "Orders",

            nullable: false,

            oldClrType: typeof(string),

            oldNullable: true);



        migrationBuilder.AddUniqueConstraint(

            name: "AK_Orders_OrderNumber",

            table: "Orders",

            column: "OrderNumber");

    }



    protected override void Down(MigrationBuilder migrationBuilder)

    {

        migrationBuilder.DropUniqueConstraint(

            name: "AK_Orders_OrderNumber",

            table: "Orders");



        migrationBuilder.AlterColumn<string>(

            name: "OrderNumber",

            table: "Orders",

            nullable: true,

            oldClrType: typeof(string));

    }

}

Now, after calling

Update-Database

I can no longer to duplicate that column

answered Nov 15 '18 at 18:10

Bassie

3,9422051

add a comment |

So it seems that calling HasAlternateKey in OnModelBuilding actually requires a new db migration before it is applied.

After calling

Add-Migration TestHasAlternateKeys

This migration was created

public partial class HasAlternateKeyTest : Migration

{

    protected override void Up(MigrationBuilder migrationBuilder)

    {

        migrationBuilder.AlterColumn<string>(

            name: "OrderNumber",

            table: "Orders",

            nullable: false,

            oldClrType: typeof(string),

            oldNullable: true);



        migrationBuilder.AddUniqueConstraint(

            name: "AK_Orders_OrderNumber",

            table: "Orders",

            column: "OrderNumber");

    }



    protected override void Down(MigrationBuilder migrationBuilder)

    {

        migrationBuilder.DropUniqueConstraint(

            name: "AK_Orders_OrderNumber",

            table: "Orders");



        migrationBuilder.AlterColumn<string>(

            name: "OrderNumber",

            table: "Orders",

            nullable: true,

            oldClrType: typeof(string));

    }

}

Now, after calling

Update-Database

I can no longer to duplicate that column

answered Nov 15 '18 at 18:10

Bassie

3,9422051

So it seems that calling HasAlternateKey in OnModelBuilding actually requires a new db migration before it is applied.

After calling

Add-Migration TestHasAlternateKeys

This migration was created

public partial class HasAlternateKeyTest : Migration

{

    protected override void Up(MigrationBuilder migrationBuilder)

    {

        migrationBuilder.AlterColumn<string>(

            name: "OrderNumber",

            table: "Orders",

            nullable: false,

            oldClrType: typeof(string),

            oldNullable: true);



        migrationBuilder.AddUniqueConstraint(

            name: "AK_Orders_OrderNumber",

            table: "Orders",

            column: "OrderNumber");

    }



    protected override void Down(MigrationBuilder migrationBuilder)

    {

        migrationBuilder.DropUniqueConstraint(

            name: "AK_Orders_OrderNumber",

            table: "Orders");



        migrationBuilder.AlterColumn<string>(

            name: "OrderNumber",

            table: "Orders",

            nullable: true,

            oldClrType: typeof(string));

    }

}

Now, after calling

Update-Database

I can no longer to duplicate that column

answered Nov 15 '18 at 18:10

Bassie

3,9422051

answered Nov 15 '18 at 18:10

Bassie

3,9422051

answered Nov 15 '18 at 18:10

Bassie

3,9422051

answered Nov 15 '18 at 18:10

Bassie

3,9422051

add a comment |

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