EF Code First Model Key Idea

How it works?

o Database

Initialize

o Data Annotation

Dmytryi Lebedinskyi

Code First ModelCode First Model

1. Define Simple Entities with connection by ID

2. Add virtual properties for lazy loading of Aggregated Fields

EF lazy loading is enabled by default

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3. Remember to preserve name convention

EF Code First uses general agreement about names.

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4. Create Data Context

DbContext is similar to EF general Data Context

Code First ModelCode First Model

Code First ModelCode First Model

5. Create a Repositories

6. What about usage?

You can work with it same like a general EF Model

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7. And what is the result?

Code First ModelCode First Model

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9. Where is Database?

Default DB Server is .\SqlExpress

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10. Change Database name

How to change DB name?

• App.config or any other Connection String supplied 

•DbConnection 

•Replace the Default Convention 

EF Code First Model

Key Idea

How it works?

Database Initialize

o Data Annotations

Code First ModelCode First Model

System.Data.Entity.Database.IDatabaseInitializer<in TContext>

CreateDatabaseIfNotExists

DropCreateDatabaseIfModelChanges

DropCreateDatabaseAlways

Database Initializers

Code First ModelCode First Model

1. Create Initializer

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2. Register Initializer

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3. And we have data if no db is created

EF Code First Model

Key Idea

How it works?

Database Initialize

Data Annotations

Since EF Code First CTP5 Data Annotations can be used for DB structure

Code First ModelCode First Model

• KeyAttribute

• StringLengthAttribute

• MaxLengthAttribute

• ConcurrencyCheckAttribute

• RequiredAttribute

• TimestampAttribute

• ComplexTypeAttribute

• ColumnAttribute (Placed on a property to specify the column name, ordinal & data type)

• TableAttribute (Placed on a class to specify the table name and schema)

• InversePropertyAttribute (Placed on a navigation property to specify the property that represents the other end of a relationship)

• ForeignKeyAttribute (Placed on a navigation property to specify the property that represents the foreign key of the relationship)

• DatabaseGeneratedAttribute (Placed on a property to specify how the database generates a value for the property (Identity, Computed or None) )

• NotMappedAttribute (Placed on a property or class to exclude it from the database)

And Validation Attributes are now also supported

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And using some MVC Magic we receive

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Questions?

:)