使用参数化查询将自动生成的ID插入ForeignKey列

Question

Unsure how to approach this using SQL parametrized queries. I can currently insert data (a customer in this scenario) into an SQL table and let the database generate and handle the primary key ID's rather than insert an ID manually along with the rest of the attributes.

My question is how would I insert this auto-generated ID into another table to it's related foreign-key column using parametrized queries? An example would be if the second table was for bookings and it had to get the ID value (Customer table) of the customer who made the booking and insert it into the FK ID column in the Booking table.

I have looked at code online and on Stack Overflow and it isn't quite what I am looking for as they are either using SQL procedures in the database designer or dealing with manually inserted ID's.

Example code I wrote:

//Insert CustomerID into TestTable
public void AddCustomerIdToForeignKeyColumnInNewTable()
{
    string connectionString = ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString;

    SqlConnection myConnection = new SqlConnection(connectionString);

    String query;

    query = "INSERT INTO TestTable VALUES (@CustomerID)";
    SqlCommand dbCommand = new SqlCommand(query, myConnection);
    dbCommand.Parameters.AddWithValue("@CustomerID", whateverIdValueGoesHere);
    try
    {
        myConnection.Open();
        dbCommand.ExecuteNonQuery();
        myConnection.Close();
    }
    catch (Exception ex)
    {
        Exception e = ex;
        myConnection.Close();
    }

}

Answer 1

You can use:

 Select SCOPE_IDENTITY(); 

Right after the insert statement.

In other words:

query = "INSERT INTO TestTable VALUES (@CustomerID); SELECT SCOPE_IDENTITY();";

And then:

 var cid= dbCommand.ExecuteScalar();

cid will contain the value of the Customer ID generated by the database