a0005 linq to ado ne morebook vn 4892

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LINQ to SQL
LINQ to DataSet


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LINQ to SQL allows querying a relational structure
by converting the LINQ query into a native SQL
query.
This means… that the queries that you write in
code generates appropriate queries to access the
actual database, AUTOMATICALLY!
There are several concepts that you will come to
know in this module…
◦ How is the query written using object names (like tables
or views)?
◦ How is it validated by the compiler?
◦ When is the query generated?
◦ When is the query executed?


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You could either…
◦ Create a class and annotate it with the Table name
◦ Define Fields (which correspond to columns)
◦ Get the Data context (The DataContext class
handles the communication between LINQ and
external relational data sources)
◦ Create a Generic type
◦ Query through LINQ

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OR… use LINQ to SQL Classes in VS 2008


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Data abstraction
Working with Strongly Typed objects
Tied to the object model and NOT to the
database
Query semantics is much more meaningful
Right now, ONLY SQL is supported, but going
forward there will be more providers which

would provide access to different databases
Once new providers come in, you could
connect to any database with virtually the
same code base