Pass table value type to SQL Server stored procedure via Entity Framework

Lets say you want to send a table with a single column of GUIDs.

First we need to create a structure using SqlMetaData which represents the schema of the table (columns).

var tableSchema = new List<SqlMetaData>(1)
{
  new SqlMetaData("Id", SqlDbType.UniqueIdentifier)
}.ToArray();

Next you create a list of records that match the schema using SqlDataRecord.

var tableRow = new SqlDataRecord(tableSchema);
tableRow.SetGuid(0, Guid.NewGuid());
var table = new List<SqlDataRecord>(1)
{
  tableRow
};

Then create the SqlParameter:

var parameter = new SqlParameter();
parameter.SqlDbType = SqlDbType.Structured;
parameter.ParameterName = "@UserIds";
parameter.Value = table;

var parameters = new SqlParameter[1]
{
  parameter
};

Then simply call the stored procedure by using the Database.SqlQuery.

IEnumerable<ReturnType> result;
using (var myContext = new DbContext())
{
  result = myContext.Database.SqlQuery<User>("GetUsers", parameters)
    .ToList();         // calls the stored procedure
    // ToListAsync();  // Async
{

In SQL Server, create your User-Defined Table Type (I suffix them with TTV, Table Typed Value):

CREATE TYPE [dbo].[UniqueidentifiersTTV] AS TABLE(
  [Id] [uniqueidentifier] NOT NULL
)
GO

Then specify the type as a parameter (don't forget, Table Type Values have to be readonly!):

CREATE PROCEDURE [dbo].[GetUsers] (
  @UserIds [UniqueidentifiersTTV] READONLY
) AS
BEGIN
  SET NOCOUNT ON

  SELECT u.* -- Just an example :P
  FROM [dbo].[Users] u
  INNER JOIN @UserIds ids On u.Id = ids.Id
END