DbMigration.AlterstoredProcedure (Entity Framework migration): How to represent type smallmoney?

问题

In Entity Framework 6.1, in a C# code-based migration (using System.Data.Entity.Migrations.DbMigration), when altering a stored procedure definition using the DbMigration.AlterStoredProcedure method, what's the proper syntax for adding or modifying a stored procedure parameter of the smallmoney type (on SQL Server 2012)?

For example, if I have a migration method that modifies an existing SQL Server stored procedure which takes three parameters, of type int, varchar, and smallmoney respectively:

public partial class MyCustomMigration : DbMigration
{
    public override void Up()
    {
        this.AlterStoredProcedure("dbo.EditItem", c => new
        {
            ItemID = c.Int(),
            ItemName = c.String(),
            ItemCost = /* What goes here to represent the smallmoney SQL Server type? */
        },
        @" (New sproc body SQL goes here) ");
    }

    // ...
}

回答1:

Thanks, nemesv, for the hint in your comment! What I was missing is that the types being specified while setting up the stored procedure parameters, i.e. "Int" and "String" in:

c => new
    {
        ItemID = c.Int(),
        ItemName = c.String(),
        //...
    }

...are actually methods, and each of those methods -- on class System.Data.Entity.Migrations.Builders.ParameterBuilder -- has a set of optional parameters which affect the SQL generated from the migration script.

In the case of a smallmoney-type stored procedure argument, I ended up using:

    ItemCost = c.Decimal(precision: 10, scale: 4, storeType: "smallmoney")

The values of precision: 10 and scale: 4 are from the MSDN article money and smallmoney (Transact-SQL), which specifies that smallmoney has precision (total # of digits) of 10 and scale (# of digits to the right of the decimal point) of 4 (for SQL Server 2008 and higher).

So my complete migration code was:

public override void Up()
{
    this.AlterStoredProcedure("dbo.EditItem", c => new
    {
        ItemID = c.Int(),
        ItemName = c.String(),
        ItemCost = c.Decimal(precision: 10, scale: 4, storeType: "smallmoney")
    },
    @" (New sproc body SQL goes here) ");
}

Which produced the SQL:

ALTER PROCEDURE [dbo].[EditItem]
    @ItemID [int],
    @ItemName [nvarchar](max),
    @ItemCost [smallmoney]
AS
BEGIN
    (New sproc body SQL goes here)
END

来源：https://stackoverflow.com/questions/27696728/dbmigration-alterstoredprocedure-entity-framework-migration-how-to-represent

标签

sql-server

entity-framework

entity-framework-6.1