DevForce Classic: Well I know how to save a list of entities. But just wondering how to save just one

Well I know how to save a list of entities. But just wondering how to save just one

Printed From: IdeaBlade
Category: DevForce
Forum Name: DevForce Classic
Forum Discription: For .NET 2.0
URL: http://www.ideablade.com/forum/forum_posts.asp?TID=281
Printed Date: 14-Apr-2026 at 4:24pm

Topic: Well I know how to save a list of entities. But just wondering how to save just one

Posted By: Customer
Subject: Well I know how to save a list of entities. But just wondering how to save just one
Date Posted: 16-Jul-2007 at 1:32pm

What is the most efficient way to add or edit one entity to the database.

Replies:

Posted By: IdeaBlade
Date Posted: 16-Jul-2007 at 1:34pm

I am not sure what you mean by "most efficient". I assume that you mean "best practice". If that's what you mean, I would look in the Developer's Guide and the Tutorials.

Remember that adding or modifying an entity is a 2 step process:

(1) Add the entity to the cache or modify an existing entity in the cache

(2) Save the entity from the cache to the database

I have a feeling that I don't quite understand your question, so feel free to respond.

Posted By: Customer
Date Posted: 16-Jul-2007 at 1:40pm

Well I know how to save a list of entities. But just wondering how to save just one. Create one entity then add it to the database.

Posted By: IdeaBlade
Date Posted: 16-Jul-2007 at 1:44pm

Make an EntityList.

Add the one entity that you want to save to the EntityList.

Save the single entity using this signature: SaveChanges(IEnumerable) Method

Here is a code example:

private void SaveSample() {
  PersistenceManager pm = PersistenceManager.DefaultManager;

  // Retrieve a single Order and its Customer
  Order order = pm.GetEntity<Order>(new PrimaryKey(typeof(Order), 10275));
  Customer cust = order.Customer;

  // Change the address in both Order and Customer
  order.ShipAddress = "100 Broadway";
  cust.Address = "100 Broadway";

  // Now save -- using a save list and SaveOptions.
  EntityList<Entity> changedEntities = new EntityList<Entity>();
  changedEntities.Add(order);
  changedEntities.Add(cust);
  SaveOptions options = new SaveOptions();
  options.IsTransactional = true;
  options.ThrowExceptionOnSaveFailure = ThrowExceptionRule.Never;

  SaveResult sr = pm.SaveChanges(changedEntities, options);