Zeeshan Hirani

Configuring Existing DataBase with Many-to-Many using Code First

zhirani — Thu, 09 Dec 2010 02:33:45 GMT

With CTP5 of Code First, you can easily map existing database schema to classes in your project. It allows you to configure what class and property gets mapped to what table and column in the database. Code First gives you two options to configure...(read more)

Builder Methods to create dynamic esql queries

zhirani — Wed, 01 Dec 2010 05:16:55 GMT

In the current project, I am working on, I make use of esql heavily. One of the reason is because I am still using EF v1 which has limited support for linq queries. The second reason is, if you have dynamic queries which are build on what user selects...(read more)

Filtering and Ordering Include

zhirani — Sat, 13 Nov 2010 03:25:16 GMT

Lot of times in your application, you have a requirement to eagerly load related collection but you want to load the collection partially and also have the data sorted when before it is materialized at the client layer. Currently in EF, there is no direct...(read more)

Binding Stored Procedure Result from Entity Framework to ObjectDataSource Control

zhirani — Wed, 03 Nov 2010 03:11:23 GMT

Not too long ago someone asked me how can they bind data returned from stored procedure to a gridview control. There are several ways to achieve that. You can either use EntityDataSource or ObjectDataSource Control. I find it easier to use ObjectDataSource...(read more)

Using GetObjectByKey to short circuit database call

zhirani — Thu, 21 Oct 2010 22:16:53 GMT

There are several ways to query for a single entity using Linq such as First or Single. For instance in the code below we are retrieving customer based on CustomerID If you execute the above code 5 times with the same object context, EF will execute the...(read more)

Inserting,Updating and Deleting entity using Stored Procedures

zhirani — Thu, 14 Oct 2010 06:07:27 GMT

If you have used entity framework with stored procedure, you would realize it has a great designer and runtime support. Yes there are few gotchas and loose ends that needs to be fixed but it does the job 99% of the time. In this blog, I will show you...(read more)

Upgrading Independent Association to Foreign Key Association

zhirani — Wed, 13 Oct 2010 05:15:18 GMT

In EF when you want to define a relationship between two entities, you typically use an association. An association can be many-to-many, 1.. 0..1, many-to-1 etc. Typically you would have tables in the database which are related to each other using foreign...(read more)

Thanks EF4. Now i can put my orderby clause anywhere

zhirani — Sun, 10 Oct 2010 20:28:39 GMT

Well most folks wouldn’t have a clue as to what the title of my posting says. This is a problem that stems from EF v1 but is now solved for the most part. in EF4.0. In version 1 of EF, it was recommended that you put your order by operation as the...(read more)

Watch out for StartsWith when upgrading from .net 3.5 to 4.0

zhirani — Thu, 07 Oct 2010 03:51:16 GMT

Currently I am working on .net 3.5 project so i am having to live with Entity Framework. v1. Anyways i was working on a linq query that was making use of StartsWith operator. For some reason based on which page you are coming from the value passed in...(read more)

Which one is faster SingleOrDefault or FirstOrDefault

zhirani — Mon, 20 Sep 2010 18:32:24 GMT

Generally, I don't see too much performance problem whether you use Single Or First. However if you have a table with lots of columns like 300 you might notice slight improvement if you use FirstOrDefault. Before we go deeper into the performance difference...(read more)

Lazy Loading Related Properties

zhirani — Fri, 06 Aug 2010 04:37:06 GMT

Lot of times in our application we do not perform eager loading on related entities because we don’t need to display them on the UI unless some action occurs. So we fetch those entities lazily only when we need them. However have you ever felt the need...(read more)

Removing entity from a Related Collection

zhirani — Fri, 23 Jul 2010 16:13:46 GMT

I have seen this misunderstanding starting to popup more often on how to delete an entity from a related collection. Suppose we have the following entity data model where a Person has many Phones identified by 1-to-many association as shown. Problem:...(read more)

Setting Entity Key for a view

zhirani — Tue, 06 Jul 2010 15:14:55 GMT

When you import a database view using Entity Data Model wizard,you will get an entity that has the same number of columns and data type as the view does.Suppose I have the following view in my database. When I import the view I get the following entity...(read more)

Search for an entity in your Entity Data Model

zhirani — Mon, 05 Jul 2010 23:07:30 GMT

Last week i discovered a feature of Entity Data Model which i have not seen extensively being promoted. I accidentally run into it because of the size of my model. If you have a large model and want to search for an entity, it becomes tedious to zoom...(read more)

Watch out for let operator in linq to entities

zhirani — Mon, 14 Jun 2010 16:27:49 GMT

LINQ has a really cool operator call Let that lets you declare variables inside the query. The benefit i find in using let is, it makes my query much easier to read because using Let keyword i can create a variable and assign it a calculated value. Then...(read more)