dbview.htm

The goal of this library is to make ODBC recordsets look just like an STL container. As a user, you

	{
		*write_it = *ex_it;
	 	cout << "Writing element #" << write_it.GetCount() + 1<< endl;
	}
}
</code></pre>


<h3>Public Base Classes</h3>

<p>None.</p>

<h3>Template parameters</h3>

<table border="1">
    <tr>
        <th>Parameter </th>
        <th>Description </th>
        <th>Default </th>
    </tr>
    <tr>
        <td valign="top"><tt>DataObj</tt> </td>
        <td valign="top">The type of object that will be written
        to the <font size="2" face="Courier New">DBView</font>.
        This object will be bound through use of the <font
        size="1" face="Courier New">BCA</font><font size="2"> </font>to
        the appropriate columns in the database. The set of value
        types of an <tt>DBView::insert_iterator</tt> consists of
        a single type, <font size="2" face="Courier New">DataObj</font>.
        </td>
        <td valign="top">&nbsp; </td>
    </tr>
    <tr>
        <td valign="top"><tt>ParamObj</tt> </td>
        <td valign="top">The type of object that will be used to
        specify the postfix parameters to the <font size="2"
        face="Courier New">DBView</font>.</td>
        <td valign="top"><font size="2" face="Courier New">DefaultParamObj&lt;DataObj&gt;</font>&nbsp;
        </td>
    </tr>
</table>

<p>&nbsp;</p>

<h3>Notation</h3>

<table border="0">
    <tr>
        <td valign="top"><tt>X</tt> </td>
        <td valign="top">A type that is a model of DBView </td>
    </tr>
    <tr>
        <td valign="top"><tt>a</tt> </td>
        <td valign="top">Object of type <tt>X</tt> </td>
    </tr>
    <tr>
        <td valign="top"><tt>t</tt> </td>
        <td valign="top">Object of type <tt>X::value_type</tt> </td>
    </tr>
    <tr>
        <td valign="top"><tt>p</tt>, <tt>q</tt> </td>
        <td valign="top">Object of type <tt>X::iterator</tt> </td>
    </tr>
</table>

<p>&nbsp;</p>

<h3>Associated types</h3>

<p>In addition to the types defined in a semi-<a
href="http://www.sgi.com/tech/stl/Container.html">Container</a>
, the following types are defined.:</p>

<table border="1">
    <tr>
        <td valign="top">Iterator type </td>
        <td valign="top">X::<a href="select_iterator.htm">select_iterator</a></td>
        <td valign="top">An input iterator to read records from
        the view</td>
    </tr>
    <tr>
        <td valign="top">Iterator type </td>
        <td valign="top">X::<a href="insert_iterator.htm">insert_iterator</a></td>
        <td valign="top">An output iterator to insert records
        into the view</td>
    </tr>
    <tr>
        <td valign="top">Iterator type </td>
        <td valign="top">X::<a href="update_iterator.htm">update_iterator</a></td>
        <td valign="top">An output iterator to update records in
        the view</td>
    </tr>
    <tr>
        <td valign="top">Iterator type </td>
        <td valign="top">X::<a href="delete_iterator.htm">delete_iterator</a></td>
        <td valign="top">An ouput iterator to delete records from
        the view</td>
    </tr>
</table>

<p>&nbsp;</p>

<h3>Expression semantics</h3>

<table border="1">
    <tr>
        <th>Name </th>
        <th>Expression </th>
        <th>Precondition </th>
        <th>Semantics </th>
        <th>Postcondition </th>
    </tr>
    <tr>
        <td valign="top">Default constructor </td>
        <td valign="top"><pre>X a(const string &amp;tableList, 
const <a href="BCA.htm">BCA</a> &amp;bca_functor = DefaultBCA&lt;DataObj&gt;(),
const string &amp;postfix = &quot;&quot;, 
const <a href="BPA.htm">BPA</a> &amp;bpa_functor = DefaultBPA&lt;ParamObj&gt;(),
const <a href="SelVal.htm">SelVal</a> sel_val = DefaultSelVal&lt;DataObj&gt;(),
const <a href="InsVal.htm">InsVal</a> ins_val = DefaultInsVal&lt;DataObj&gt;(),
<a href="DBConnection.htm">DBConnection</a> &amp;connection = DBConnection::GetDefaultConnection())</pre>
        </td>
        <td valign="top">&nbsp; </td>
        <td valign="top">Creates an empty container bound to a
        table, using the database connection specified in the
        connection object. The actual queries run againt this
        table are built by the select, insert, update and delete
        iterators (see these iterators for details) but
        essentially follow the following format:<p><font size="2"
        face="Courier New">&quot;SELECT &quot; + &lt;columns
        listed in bca_fn()&gt; + &quot; FROM &quot; + tableList +
        postfix</font></p>
        <p>In the SQL clause, users may also specify dynamic
        parameters through the use of SQL <font size="2"
        face="Courier New">'(?)'</font> syntax. In this case <a
        href="BPA.htm"><font size="2" face="Courier New">BPA</font></a>
        is a class that is used to hold these runtime parameters
        and <font size="2" face="Courier New">bpa_functor </font>is a
        functor used to associate fields in the parameters class
        with parameter fields in the query.</p>
        </td>
        <td valign="top">The size of the container is <font
        size="3" face="Times New Roman"><tt>0. </tt></font>
	<font size="3" face="Times New Roman">Rows are operated
        on by obtaining the appropriate iterator from the
        container.</tt></font></td>
    </tr>
</table>

<p>&nbsp;</p>

<h3>Members</h3>

<table border="1">
    <tr>
        <th>Member </th>
        <th>Where defined </th>
        <th>Description </th>
    </tr>
    <tr>
        <td valign="top"><tt>value_type</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">The type of object, <tt>T</tt>, stored
        in the <font size="2" face="Courier New">DBView</font>.
        In this case<font size="2" face="Courier New"> T =
        DataObj</font></td>
    </tr>
    <tr>
        <td valign="top"><tt>pointer</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">Pointer to <tt>T</tt>. </td>
    </tr>
    <tr>
        <td valign="top"><tt>reference</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">Reference to <tt>T</tt> </td>
    </tr>
    <tr>
        <td valign="top"><tt>const_reference</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">Const reference to <tt>T</tt> </td>
    </tr>
    <tr>
        <td valign="top"><tt>size_type</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">An unsigned integral type. </td>
    </tr>
    <tr>
        <td valign="top"><tt>difference_type</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">A signed integral type. </td>
    </tr>
    <tr>
        <td valign="top"><tt>iterator</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">Iterator used to iterate through a <font
        size="2" face="Courier New">DBView</font>. The default
        iterator for<font size="2" face="Courier New"> DBView</font>
        is the <font size="2" face="Courier New">select_iterator</font>.</td>
    </tr>
    <tr>
        <td valign="top"><tt>const_iterator</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">Const iterator used to iterate through a
        <font size="2" face="Courier New">DBView</font>. (<tt>iterator</tt>
        and <tt>const_iterator</tt> are the same type.) </td>
    </tr>
    <tr>
        <td valign="top"><tt>reverse_iterator</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/ReversibleContainer.html">Reversible
        Container</a> </td>
        <td valign="top">Iterator used to iterate backwards
        through a <font size="2" face="Courier New">DBView</font>.
        </td>
    </tr>
    <tr>
        <td valign="top"><tt>const_reverse_iterator</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/ReversibleContainer.html">Reversible
        Container</a> </td>
        <td valign="top">Const iterator used to iterate backwards
        through a <font size="2" face="Courier New">DBView</font>.
        (<tt>Reverse_iterator</tt> and <tt>const_reverse_iterator</tt>
        are the same type.) </td>
    </tr>
    <tr>
        <td valign="top"><tt>iterator begin()</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">Returns an <tt>iterator</tt> pointing to
        the beginning of the DBView. </td>
    </tr>
    <tr>
        <td valign="top"><tt>const_iterator begin() const</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">Returns a <tt>const_iterator</tt> pointing to
        the beginning of the DBView. </td>
    </tr>
    <tr>
        <td valign="top"><tt>iterator end()</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">Returns a <tt>const_iterator</tt> pointing to
        the end of the DBView. </td>
    </tr>
    <tr>
        <td valign="top"><tt>const_iterator end() const</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">Returns a <tt>const_iterator</tt> pointing to
        the end of the DBView. </td>
    </tr>
    <tr>
        <td valign="top"><pre><tt>X a(const string &amp;tableList, 
const </tt><a href="BCA.htm"><tt>BCA</tt></a><tt> &amp;bca_functor = DefaultBCA&lt;DataObj&gt;(),
const string &amp;postfix = &quot;&quot;, 
const </tt><a href="BPA.htm"><tt>BPA</tt></a><tt> &amp;bpa_functor = DefaultBPA&lt;ParamObj&gt;(),
const </tt><a href="SelVal.htm"><tt>SelVal</tt></a><tt> sel_val = DefaultSelVal&lt;DataObj&gt;(),
const </tt><a href="InsVal.htm"><tt>InsVal</tt></a><tt> ins_val = DefaultInsVal&lt;DataObj&gt;(),
</tt><a href="DBConnection.htm"><tt>DBConnection</tt></a><tt> &amp;connection = DBConnection::GetDefaultConnection())</tt></pre>
        </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">Creates an empty <font size="2"
        face="Courier New">DBView</font>. </td>
    </tr>
    <tr>
        <td valign="top"><tt>DBView(const DBView&amp;)</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">The copy constructor. </td>
    </tr>
    <tr>
        <td valign="top"><tt>DBView&amp; operator=(const
        DBView&amp;)</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">The assignment operator </td>
    </tr>
    <tr>
        <td valign="top"><font size="2" face="Courier New">void
        set_io_handler(IOHandler&lt;DataObj, ParamObj&gt;)</font></td>
        <td valign="top"><font size="2" face="Courier New">DBView</font></td>
        <td valign="top">Sets the <font size="2"
        face="Courier New">IOHandler</font> for this view.  Iterators created from this view
	will then use this handler by default until set by the iterator's version of this
	method. The <font size="2" face="Courier New">IOHandler </font>will
        try to handle exceptions thrown by such iterators and tell
        the code which caught the exception whether to suppress
        the error or still throw.</td>
    </tr>
    <tr>
        <td valign="top"><font size="2" face="Courier New">template&lt;class
        UserHandler&gt; const UserHandler &amp; get_io_handler(UserHandler
        *dummy) const</font></td>
        <td valign="top"><font size="2" face="Courier New">DBView</font></td>
        <td valign="top">Returns the current<font size="2"
        face="Courier New"> IOHandler</font> for this object cast
        to the actual type of the handler based on the dummy
        pointer passed in. If the dynamic cast of the <font
        size="2" face="Courier New">IOHandler</font> object
        fails, an exception will be thrown.</td>
    </tr>
    <tr>
        <td valign="top"><font size="2" face="Courier New">IOHandler&lt;DataObj,
        ParamObj&gt; &amp;get_io_handler() const</font></td>
        <td valign="top"><font size="2" face="Courier New">DBView</font></td>
 	<td valign="top">Returns the current<font size="2"
        face="Courier New"> IOHandler</font> for this object as a
        raw <font size="2" face="Courier New">IOHandler</font>
        object. You must cast to the actual type of the handler
        to be able to access any of your handler's public members.</td>
    </tr>
    <tr>
        <td valign="top"><tt>void swap(DBView&amp;)</tt> </td>
        <td valign="top"><a
        href="http://www.sgi.com/tech/stl/Container.html">Container</a>
        </td>
        <td valign="top">Swaps the contents of two <font size="2"
        face="Courier New">DBView's</font>. </td>
    </tr>
</table>

<h3>See also</h3>

<p><a
href="http://www.sgi.com/tech/stl/MultipleAssociativeContainer.html">Multiple
Associative Container</a>, <a href="BCA.htm"><font size="2"
face="Courier New">BCA</font></a><font size="2"
face="Courier New">, </font><a href="BPA.htm"><font size="2"
face="Courier New">BPA</font></a><font size="2"
face="Courier New">, </font><a href="InsVal.htm"><font size="2"
face="Courier New">InsVal</font></a><font size="2"
face="Courier New">, </font><a href="SelVal.htm"><font size="2"
face="Courier New">SelVal</font></a><font size="2"
face="Courier New">, </font><a href="db_iterator.htm"><font
size="2" face="Courier New">DB_iterator</font></a><a
href="db_iterator.htm"><font size="2"><!--start footer--></font></a> </p>


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