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PATH WebObjects 4.0 Documentation > EOF Tools and Techniques

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What a New Model Includes

When you create a new model, the information it includes depends on how completely you've specified the underlying database. EOModeler can read all of the following from a database and include it in a default model:

Table and column names
Column data types, including the width constraint of string data types
Primary keys
User constraints, such as null constraints and uniqueness
Foreign key definitions (which are expressed in a model as relationships)
Stored procedures

A model contains not only the information it reads from the database, but values it derives from that information, including:

Entity and attribute names
A mapping between the data type of a database column and a corresponding value class, such as String, Number, or NSGregorianDate (NSString, NSNumber, or NSCalendarDate in Objective-C). See the class specification for each adaptor for a listing of the adaptor's default database type to value class mapping.

EOModeler derives entity names by taking a database table name and making all of it lowercase except for the first letter. It then removes underbar (_) characters and capitalizes any characters following underbars. For example:


Database Table	Entity Name
EMPLOYEE	Employee
EMPLOYEE_PHOTO	EmployeePhoto
TEST_OF_SEVERAL_WORDS	TestOfSeveralWords

Attribute names are based on corresponding database columns. They're derived in the same way as entities, except that EOModeler doesn't capitalize the first character. For example:

Database Column Attribute Name

NAME name

FIRST_NAME firstName

MOVIE_ID movieId

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