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7: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\f0\b\i0\ulnone\fs36\fc0\cf0 AssociationExample
8: \b0\fs24 \
9: by Mai Nguyen, NeXT Developer Support Team\
10: \
11:
12: \b\fs28 Overview
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14:
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16: The current version of DBKit does not provide a way to filter the records fetched by a detail FetchGroup. DBKit does not allow a qualifier to be built into a relationship, nor does it allow a qualifier to be permanently attached to a FetchGroup. The Association example provides a way to do filtering of detail records by using a subclass of DBAssociation that replaces the default association which exists between the master FetchGroup and the detail FetchGroup. In this example, the user can change the criteria of the qualifier by entering a new value in the salary field and pressing the
17: \b Fetch:
18: \b0 button. The example is built such that you can easily reuse the object
19: \b QualifiedAssociation
20: \b0 in your custom application.\
21: In order to run this example, you need to have access to an Oracle server and an Oracle demo database as described by the
22: \b OracleDemo.dbmodela
23: \b0 model file.\
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25: \fc1\cf1 \
26:
27: \b\fs28 Program Organization\
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30:
31: \b Major Classes in the Application
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33: \
34: \
35:
36: \pard\tx2880\tx2900\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fi-1900\li1900\fc1\cf1 Controller A general tester object. This object is for testing whether the custom association works properly. It is managing the UI of this example.\
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40: \pard\tx2880\tx2900\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fi-2920\li2920\fc1\cf1 QualifiedAssociation A subclass of DBAssociation. It overrides the method called when fetching, and add some new methods for setting up the proper qualifier. \
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44: \pard\tx960\tx1920\tx2880\tx3840\tx4800\tx5760\tx6720\tx7680\tx8640\tx9600\fc1\cf1 \
45:
46: \b\fs28 Topics Of Interest\
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49: - How to set up a new DBAssociation between the master fetchgroup and the detail fetchgroup
50: \b0 \
51: See the method
52: \b initAndReplaceAssociationTo:
53: \b0 in the file QualifiedAssociation.m\
54:
55: \pard\tx1340\tx2680\tx4020\tx5360\tx6720\tx8060\tx9400\tx10740\tx12080\tx13440\fc1\cf1 \
56: Last Edited: July 1993
57: }
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