There are several ways that the Entity Framework can load related data into the navigation properties of an entity:
When the entity is first read, related data isn’t retrieved. However, the first time you attempt to access a navigation property, the data required for that navigation property is automatically retrieved. This results in multiple queries sent to the database — one for the entity itself and one each time that related data for the entity must be retrieved.
When the entity is read, related data is retrieved along with it. This typically results in a single join query that retrieves all of the data that’s needed. You specify eager loading by using the Include method.
This is similar to lazy loading, except that you explicitly retrieve the related data in code; it doesn’t happen automatically when you access a navigation property. You load related data manually by getting the object state manager entry for an entity and calling the Collection.Load method for collections or the Reference.Load method for properties that hold a single entity. (In the following example, if you wanted to load the Administrator navigation property, you’d replace Collection(x => x.Courses) with Reference(x => x.Administrator).)
var context1 = new Model1Container();
var myEntity = from c in context1.PersonalInfoSystems
where c.Username == "farhad"
LINQ queries begin with the FROM clause, rather than the SELECT clause that most of us are familiar with in other query languages.
When LINQ was being created, query statements did begin with SELECT. However, the developers at Microsoft quickly realized that identifying the type that is being used up front enabled IntelliSense to provide meaningful suggestions as the rest of the query was constructed.
According to Microsoft’s Y. Alan Griver, who was very involved with the LINQ project
during its early stages, the Microsoft developers jokingly referred to this syntax as “Yoda
speak” when they altered the syntax for the sake of IntelliSense.
The foundations of Agile Software Development and Project Management are, without a doubt, the Agile Manifesto and the Declaration of Inter-Dependence.
“We are uncovering better ways of developing software by doing it and helping others do it.
Through this work we have come to value:
- Individuals and interactions over processes and tools
- Working software over comprehensive documentation
- Customer collaboration over contract negotiation
- Responding to change over following a plan
Along with these four values, the Agile Manifesto has twelve principles:
1. Our highest priority is to satisfy the customer through early and continuous delivery of valuable software.
2. Welcome changing requirements, even late in development. Agile processes harness change for the customer’s competitive advantage.
3. Deliver working software frequently, from a couple of weeks to a couple of months, with a preference to the shorter timescale.
4. Business people and developers must work together daily throughout the project.
5. Build projects around motivated individuals. Give them the environment and support they need, and trust them to get the job done.
6. The most efficient and effective method of conveying information to and within a development team is face-to-face conversation.
7. Working software is the primary measure of progress.
8. Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely.
9. Continuous attention to technical excellence and good design enhances agility.
10. Simplicity—the art of maximizing the amount of work not done—is essential.
11. The best architectures, requirements, and designs emerge from self-organizing teams.
12. At regular intervals, the team reflects on how to become more effective, then tunes and adjusts its behavior accordingly.
Version after version HTML tried to be more effective and flexible. One of the biggest problems in html was that it couldn’t explain a page very well. It was static and does not have interactions that might be needed.
Now HTML5 coming with a lot of new tags and powerful semantic tags for Search Engine Optimization (SEO) purposes.