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1.1     ! root        1: {\rtf0\ansi{\fonttbl\f0\fswiss Helvetica;\f1\fmodern Ohlfs;}
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        !             7: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\f0\b\i0\ulnone\fs36\fc0\cf0 MasteringDetails
        !             8: \b0\fs24 \
        !             9: by Craig Federighi, EO Development Team\
        !            10: \
        !            11: 
        !            12: \b\fs28 Overview
        !            13: \b0\fs24 \
        !            14: \
        !            15: This example presents a generic scheme for assigning relationship keys automatically for insertions and deletions in detail controllers.  The implementation of this is fairly complex, but the result is a significant simplification in the code required to implement applications that allow editing master-detail relationships.\
        !            16: \
        !            17: 
        !            18: \b\fs28 \
        !            19: Demo Application Features\
        !            20: 
        !            21: \b0\fs24 \
        !            22: The application allows the user to enter and edit employee information.  The employee data has several interesting relationships:\
        !            23: 
        !            24: \pard\tx980\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fi-220\li960\fc0\cf0 �      A to-one foreign key to primary key relationship for employee to department.\
        !            25: �      A many-to-many relationship between employee and project.\
        !            26: 
        !            27: \pard\tx980\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fi-220\li960\fc0\cf0 �      Primary key to primary key relationship for Quote and Picture.\
        !            28: 
        !            29: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fc0\cf0 The primary purpose of this example is to show how key assignment can be handled in a general way when records are inserted in detail controllers with these sort of relationships.\
        !            30: \
        !            31: 
        !            32: \b Additional Features:
        !            33: \b0  \
        !            34: \
        !            35: 
        !            36: \pard\tx980\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fi-220\li960\fc0\cf0 �      The Quote field demonstrates storing rich text in the database.  \
        !            37: �      An image well allows storage and retrieval of images.\
        !            38: �      Departments and Projects are selected by selecting from a list of available choices presented in a scrolling list (pick list).  This is done with a new association type.\
        !            39: �      New objects are automatically assigned unique primary keys.\
        !            40: 
        !            41: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\b\fs28\fc0\cf0 \
        !            42: The Example Folder\
        !            43: 
        !            44: \b0\fs24 \
        !            45: The example contains the following:\
        !            46: \
        !            47: 
        !            48: \pard\tx1920\tx2880\tx3320\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fi-3320\li3320\fc0\cf0 EOFExtensions.subproj      -       A application-independent relationship management facility.\
        !            49:     KeyGenerator               -       Much like the UniqueKey example, this provides a facility for assigning unique primary keys to objects.\
        !            50:     ValueForKey                -       A category on NSObject to provide single key versions of takeValuesFromDictionary and valuesForKeys.\
        !            51:     RelationshipKeySetter      -       The brains of this example.  Provides categories on EORelationship to perform key assignment on master or detail objects in order for the relationship between them to hold in the database.\
        !            52:     SavvyControllerDel...      -       A generic EOController delegate that uses the RelationshipKeySetter to assign keys correctly when objects are inserted or deleted in detail controllers.\
        !            53:     SelectionInsertionAs...    -       An EOAssociation subclass that inserts and deletes objects in its controller based on the selection in its destination controller.\
        !            54: 
        !            55: \pard\tx1920\tx2880\tx3320\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fi-3320\li3320\fc0\cf0     ResetRelationships     -       Not actually used in this example.  Provides a category on EODatabaseChannel for updating the relationship pointers of an EO when its foreign key values have been modified.  This plays the opposite role to the RelationshipKeySetter.\
        !            56: 
        !            57: \pard\tx1920\tx2880\tx3320\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fi-3320\li3320\fc0\cf0 EmpController              -       The main controller in this application.  Sets up associations, performs initial fetches, and provides an insert operation to add new employees.  As a subclass of the generic SavvyControllerDelegate it acts as a delegate for detail controllers, performing key assignments for the insertion and deletion of objects.\
        !            58:  Employee              -       An example EO class.\
        !            59: 
        !            60: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fc0\cf0 \
        !            61: \
        !            62: 
        !            63: \b\fs28\fc1\cf1 Running the Example
        !            64: \b0\fs24\fc0\cf0 \
        !            65: \
        !            66: Select an employee from the table view; notice that the department and project lists at the bottom of the window select the department and projects for the selected employee.  You can edit the employee in several ways:\
        !            67: 
        !            68: \pard\tx980\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fi-220\li960\fc0\cf0 �      Re-assign an employee to a different department by clicking on the new department in the departments list. \
        !            69: �      Assign the employee to additional projects by shift clicking on a new project in the projects list.  \
        !            70: �      Add a picture for the employee by dragging an image into the image well.\
        !            71: �      Type a new "quote" for the employee by typing in the Quote text view.  This is an RTFD field, so you can use rich text and even add images or files.\
        !            72: 
        !            73: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fc0\cf0 Save your changes by either clicking the save button or selecting a different employee.\
        !            74: \
        !            75: Add a new employee by clicking the Add button.  Enter the new data for this employee and select save to commit the new entry to the database.\
        !            76: 
        !            77: \b \
        !            78: \
        !            79: 
        !            80: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fs28\fc1\cf1 Building For Sybase v.s. Oracle\
        !            81: 
        !            82: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\b0\fs24\fc0\cf0 This example uses the "People" database.  Scripts to create this database on your server can be found in 
        !            83: \b /NextDeveloper/Examples/EnterpriseObjects/PeopleDBScripts.
        !            84: \b0   This example includes model files for both Sybase and Oracle.  To use Oracle, do the following in a shell:\
        !            85: 
        !            86: \f1\fs20       cp people_Oracle.eomodel people_photo_quote.eomodel\
        !            87: 
        !            88: \f0\fs24 and then make the project.    \
        !            89: 
        !            90: \b \
        !            91: 
        !            92: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fc0\cf0 \
        !            93: 
        !            94: \fs28\fc1\cf1 Known Limitations\
        !            95: 
        !            96: \b0\fs24\fc0\cf0 \
        !            97: The SavvyDelegate performs non-optimal database updates, sometimes updating an object twice or inserting an object and immediately updating it as part of a single save operation.
        !            98: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fc0\cf0 \
        !            99: \
        !           100: 
        !           101: \b\fs28\fc1\cf1 \
        !           102: Possible Enhancements\
        !           103: 
        !           104: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\b0\fs24\fc0\cf0 The SavvyDelegate does not handle propagating deletions from a master to its details.  It would be nice if we could just delete an employee from the master and have other associated data dropped automatically.
        !           105: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\b\fs28\fc1\cf1 \
        !           106: 
        !           107: \pard\tx980\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\b0\fs24\fi-220\li960\fc0\cf0 \
        !           108: 
        !           109: \pard\tx1140\tx2300\tx3440\tx4600\tx5760\tx6900\tx8060\tx9200\tx10360\tx11520\fc1\cf1 This app performs no validation on employee data.  Combining the SavvyDelegate here and the ValidatingDelegate from the Validation example could improve that situation.\
        !           110: \
        !           111: \
        !           112: 
        !           113: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\b\fs28\fc1\cf1 Philosophical Reflections\
        !           114: 
        !           115: \pard\tx1140\tx2300\tx3440\tx4600\tx5760\tx6900\tx8060\tx9200\tx10360\tx11520\b0\fs24\fc1\cf1 \
        !           116: 
        !           117: \pard\tx1140\tx2300\tx3440\tx4600\tx5760\tx6900\tx8060\tx9200\tx10360\tx11520\fc1\cf1 This example shows how to eliminate a lot of the drudgery associated with assigning keys in detail controllers.  One might ask why the assignment is being performed at the controller level at all.  For example, what if I create an employee object on a screen that does not display the department or employee picture (and therefore doesn't have detail controllers for these properties)?  I'd still like the employee to automatically be assigned a default department and (possibly empty) picture and quote objects.\
        !           118: \
        !           119: A better (and less UI-centric) way to handle the task of relationship management is to perform the work of the Savvy(Controller)Delegate in a delegate of the EODatabaseChannel, and/or in the EO itself.  This is left as an exercise for the reader!\
        !           120: 
        !           121: \pard\tx1140\tx2300\tx3440\tx4600\tx5760\tx6900\tx8060\tx9200\tx10360\tx11520\fc1\cf1 \
        !           122: \
        !           123: 
        !           124: \b\fs28 Change History
        !           125: \b0\fs24 \
        !           126: \
        !           127: 17/Feb/95      Created for EOF 1.1 release (Craig Federighi)\
        !           128: 
        !           129: }

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