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27
28/*!
29 \example sql/cachedtable
30 \title Cached Table Example
31
32 The Cached Table example shows how a table view can be used to access a database,
33 caching any changes to the data until the user explicitly submits them using a
34 push button.
35
36 \image cachedtable-example.png
37
38 The example consists of a single class, \c TableEditor, which is a
39 custom dialog widget that allows the user to modify data stored in
40 a database. We will first review the class definiton and how to
41 use the class, then we will take a look at the implementation.
42
43 \section1 TableEditor Class Definition
44
45 The \c TableEditor class inherits QDialog making the table editor
46 widget a top-level dialog window.
47
48 \snippet examples/sql/cachedtable/tableeditor.h 0
49
50 The \c TableEditor constructor takes two arguments: The first is a
51 pointer to the parent widget and is passed on to the base class
52 constructor. The other is a reference to the database table the \c
53 TableEditor object will operate on.
54
55 Note the QSqlTableModel variable declaration: As we will see in
56 this example, the QSqlTableModel class can be used to provide data
57 to view classes such as QTableView. The QSqlTableModel class
58 provides an editable data model making it possible to read and
59 write database records from a single table. It is build on top of
60 the lower-level QSqlQuery class which provides means of executing
61 and manipulating SQL statements.
62
63 We are also going to show how a table view can be used to cache
64 any changes to the data until the user explicitly requests to
65 submit them. For that reason we need to declare a \c submit() slot
66 in additon to the model and the editor's buttons.
67
68 \table 100%
69 \header \o Connecting to a Database
70 \row
71 \o
72
73 Before we can use the \c TableEditor class, we must create a
74 connection to the database containing the table we want to edit:
75
76 \snippet examples/sql/cachedtable/main.cpp 0
77
78 The \c createConnection() function is a helper function provided