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+<font color="#004faf">Main Classes</font></a> + | <a href="annotated.html"> +<font color="#004faf">Annotated</font></a> + | <a href="groups.html"> +<font color="#004faf">Grouped Classes</font></a> + | <a href="functions.html"> +<font color="#004faf">Functions</font></a> +</td> +<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>TQSqlCursor Class Reference<br><small>[<a href="sql.html">sql module</a>]</small></h1> + +<p>The TQSqlCursor class provides browsing and editing of SQL +tables and views. +<a href="#details">More...</a> +<p><tt>#include <<a href="qsqlcursor-h.html">ntqsqlcursor.h</a>></tt> +<p>Inherits <a href="ntqsqlrecord.html">TQSqlRecord</a> and <a href="ntqsqlquery.html">TQSqlQuery</a>. +<p>Inherited by <a href="ntqsqlselectcursor.html">TQSqlSelectCursor</a>. +<p><a href="qsqlcursor-members.html">List of all member functions.</a> +<h2>Public Members</h2> +<ul> +<li class=fn><a href="#TQSqlCursor"><b>TQSqlCursor</b></a> ( const TQString & name = TQString::null, bool autopopulate = TRUE, TQSqlDatabase * db = 0 )</li> +<li class=fn><a href="#TQSqlCursor-2"><b>TQSqlCursor</b></a> ( const TQSqlCursor & other )</li> +<li class=fn>TQSqlCursor & <a href="#operator-eq"><b>operator=</b></a> ( const TQSqlCursor & other )</li> +<li class=fn><a href="#~TQSqlCursor"><b>~TQSqlCursor</b></a> ()</li> +<li class=fn>enum <a href="#Mode-enum"><b>Mode</b></a> { ReadOnly = 0, Insert = 1, Update = 2, Delete = 4, Writable = 7 }</li> +<li class=fn>virtual TQSqlIndex <a href="#primaryIndex"><b>primaryIndex</b></a> ( bool setFromCursor = TRUE ) const</li> +<li class=fn>virtual TQSqlIndex <a href="#index"><b>index</b></a> ( const TQStringList & fieldNames ) const</li> +<li class=fn>TQSqlIndex <a href="#index-2"><b>index</b></a> ( const TQString & fieldName ) const</li> +<li class=fn>TQSqlIndex <a href="#index-3"><b>index</b></a> ( const char * fieldName ) const</li> +<li class=fn>virtual void <a href="#setPrimaryIndex"><b>setPrimaryIndex</b></a> ( const TQSqlIndex & idx )</li> +<li class=fn>virtual void <a href="#append"><b>append</b></a> ( const TQSqlFieldInfo & fieldInfo )</li> +<li class=fn>virtual void <a href="#insert"><b>insert</b></a> ( int pos, const TQSqlFieldInfo & fieldInfo )</li> +<li class=fn>virtual void <a href="#remove"><b>remove</b></a> ( int pos )</li> +<li class=fn>virtual void <a href="#clear"><b>clear</b></a> ()</li> +<li class=fn>virtual void <a href="#setGenerated"><b>setGenerated</b></a> ( const TQString & name, bool generated )</li> +<li class=fn>virtual void <a href="#setGenerated-2"><b>setGenerated</b></a> ( int i, bool generated )</li> +<li class=fn>virtual TQSqlRecord * <a href="#editBuffer"><b>editBuffer</b></a> ( bool copy = FALSE )</li> +<li class=fn>virtual TQSqlRecord * <a href="#primeInsert"><b>primeInsert</b></a> ()</li> +<li class=fn>virtual TQSqlRecord * <a href="#primeUpdate"><b>primeUpdate</b></a> ()</li> +<li class=fn>virtual TQSqlRecord * <a href="#primeDelete"><b>primeDelete</b></a> ()</li> +<li class=fn>virtual int <a href="#insert-2"><b>insert</b></a> ( bool invalidate = TRUE )</li> +<li class=fn>virtual int <a href="#update"><b>update</b></a> ( bool invalidate = TRUE )</li> +<li class=fn>virtual int <a href="#del"><b>del</b></a> ( bool invalidate = TRUE )</li> +<li class=fn>virtual void <a href="#setMode"><b>setMode</b></a> ( int mode )</li> +<li class=fn>int <a href="#mode"><b>mode</b></a> () const</li> +<li class=fn>virtual void <a href="#setCalculated"><b>setCalculated</b></a> ( const TQString & name, bool calculated )</li> +<li class=fn>bool <a href="#isCalculated"><b>isCalculated</b></a> ( const TQString & name ) const</li> +<li class=fn>virtual void <a href="#setTrimmed"><b>setTrimmed</b></a> ( const TQString & name, bool trim )</li> +<li class=fn>bool <a href="#isTrimmed"><b>isTrimmed</b></a> ( const TQString & name ) const</li> +<li class=fn>bool <a href="#isReadOnly"><b>isReadOnly</b></a> () const</li> +<li class=fn>bool <a href="#canInsert"><b>canInsert</b></a> () const</li> +<li class=fn>bool <a href="#canUpdate"><b>canUpdate</b></a> () const</li> +<li class=fn>bool <a href="#canDelete"><b>canDelete</b></a> () const</li> +<li class=fn>bool <a href="#select-2"><b>select</b></a> ()</li> +<li class=fn>bool <a href="#select-3"><b>select</b></a> ( const TQSqlIndex & sort )</li> +<li class=fn>bool <a href="#select-4"><b>select</b></a> ( const TQSqlIndex & filter, const TQSqlIndex & sort )</li> +<li class=fn>virtual bool <a href="#select"><b>select</b></a> ( const TQString & filter, const TQSqlIndex & sort = TQSqlIndex ( ) )</li> +<li class=fn>virtual void <a href="#setSort"><b>setSort</b></a> ( const TQSqlIndex & sort )</li> +<li class=fn>TQSqlIndex <a href="#sort"><b>sort</b></a> () const</li> +<li class=fn>virtual void <a href="#setFilter"><b>setFilter</b></a> ( const TQString & filter )</li> +<li class=fn>TQString <a href="#filter"><b>filter</b></a> () const</li> +<li class=fn>virtual void <a href="#setName"><b>setName</b></a> ( const TQString & name, bool autopopulate = TRUE )</li> +<li class=fn>TQString <a href="#name"><b>name</b></a> () const</li> +<li class=fn>bool <a href="#isNull"><b>isNull</b></a> ( int i ) const</li> +<li class=fn>bool <a href="#isNull-2"><b>isNull</b></a> ( const TQString & name ) const</li> +</ul> +<h2>Protected Members</h2> +<ul> +<li class=fn>virtual TQVariant <a href="#calculateField"><b>calculateField</b></a> ( const TQString & name )</li> +<li class=fn>virtual int <a href="#update-2"><b>update</b></a> ( const TQString & filter, bool invalidate = TRUE )</li> +<li class=fn>virtual int <a href="#del-2"><b>del</b></a> ( const TQString & filter, bool invalidate = TRUE )</li> +<li class=fn>virtual TQString <a href="#toString-3"><b>toString</b></a> ( const TQString & prefix, TQSqlField * field, const TQString & fieldSep ) const</li> +<li class=fn>virtual TQString <a href="#toString"><b>toString</b></a> ( TQSqlRecord * rec, const TQString & prefix, const TQString & fieldSep, const TQString & sep ) const</li> +<li class=fn>virtual TQString <a href="#toString-4"><b>toString</b></a> ( const TQSqlIndex & i, TQSqlRecord * rec, const TQString & prefix, const TQString & fieldSep, const TQString & sep ) const</li> +</ul> +<hr><a name="details"></a><h2>Detailed Description</h2> + + +The TQSqlCursor class provides browsing and editing of SQL +tables and views. +<p> + +<p> A TQSqlCursor is a database record (see <a href="ntqsqlrecord.html">TQSqlRecord</a>) that +corresponds to a table or view within an SQL database (see <a href="ntqsqldatabase.html">TQSqlDatabase</a>). There are two buffers in a cursor, one used for +browsing and one used for editing records. Each buffer contains a +list of fields which correspond to the fields in the table or +view. +<p> When positioned on a valid record, the browse buffer contains the +values of the current record's fields from the database. The edit +buffer is separate, and is used for editing existing records and +inserting new records. +<p> For browsing data, a cursor must first <a href="#select">select</a>() data from the +database. After a successful select() the cursor is active +(<a href="ntqsqlquery.html#isActive">isActive</a>() returns TRUE), but is initially not positioned on a +valid record (<a href="ntqsqlquery.html#isValid">isValid</a>() returns FALSE). To position the cursor on +a valid record, use one of the navigation functions, <a href="ntqsqlquery.html#next">next</a>(), +<a href="ntqsqlquery.html#prev">prev</a>(), <a href="ntqsqlquery.html#first">first</a>(), <a href="ntqsqlquery.html#last">last</a>(), or <a href="ntqsqlquery.html#seek">seek</a>(). Once positioned on a valid +record, data can be retrieved from the browse buffer using +<a href="ntqsqlquery.html#value">value</a>(). If a navigation function is not successful, it returns +FALSE, the cursor will no longer be positioned on a valid record +and the values returned by value() are undefined. +<p> For example: +<p> + +<pre> TQSqlCursor cur( "staff" ); // Specify the table/view name + <a name="x2178"></a> cur.<a href="#select">select</a>(); // We'll retrieve every record + while ( cur.<a href="ntqsqlquery.html#next">next</a>() ) { + <a name="x2179"></a> <a href="ntqapplication.html#qDebug">qDebug</a>( cur.<a href="ntqsqlquery.html#value">value</a>( "id" ).toString() + ": " + + cur.<a href="ntqsqlquery.html#value">value</a>( "surname" ).toString() + " " + + cur.<a href="ntqsqlquery.html#value">value</a>( "salary" ).toString() ); + } +</pre> +<p> In the above example, a cursor is created specifying a table or +view name in the database. Then, <a href="#select">select</a>() is called, which can be +optionally parameterised to filter and order the records +retrieved. Each record in the cursor is retrieved using <a href="ntqsqlquery.html#next">next</a>(). +When next() returns FALSE, there are no more records to process, +and the loop terminates. +<p> For editing records (rows of data), a cursor contains a separate +edit buffer which is independent of the fields used when browsing. +The functions <a href="#insert">insert</a>(), <a href="#update">update</a>() and <a href="#del">del</a>() operate on the edit +buffer. This allows the cursor to be repositioned to other +records while simultaneously maintaining a separate buffer for +edits. You can get a pointer to the edit buffer using +<a href="#editBuffer">editBuffer</a>(). The <a href="#primeInsert">primeInsert</a>(), <a href="#primeUpdate">primeUpdate</a>() and <a href="#primeDelete">primeDelete</a>() +functions also return a pointer to the edit buffer and prepare it +for insert, update and delete respectively. Edit operations only +affect a single row at a time. Note that update() and del() +require that the table or view contain a <a href="#primaryIndex">primaryIndex</a>() to ensure +that edit operations affect a unique record within the database. +<p> For example: +<p> + +<pre> TQSqlCursor cur( "prices" ); + <a name="x2200"></a> cur.<a href="#select">select</a>( "id=202" ); + if ( cur.<a href="ntqsqlquery.html#next">next</a>() ) { + <a name="x2199"></a> <a href="ntqsqlrecord.html">TQSqlRecord</a> *buffer = cur.<a href="#primeUpdate">primeUpdate</a>(); + <a name="x2204"></a> double price = buffer-><a href="ntqsqlrecord.html#value">value</a>( "price" ).toDouble(); + double newprice = price * 1.05; + <a name="x2203"></a> buffer-><a href="ntqsqlrecord.html#setValue">setValue</a>( "price", newprice ); + <a name="x2201"></a> cur.<a href="#update">update</a>(); + } +</pre> +<p> To edit an existing database record, first move to the record you +wish to update. Call <a href="#primeUpdate">primeUpdate</a>() to get the pointer to the +cursor's edit buffer. Then use this pointer to modify the values +in the edit buffer. Finally, call <a href="#update">update</a>() to save the changes to +the database. The values in the edit buffer will be used to +locate the appropriate record when updating the database (see +<a href="#primaryIndex">primaryIndex</a>()). +<p> Similarly, when deleting an existing database record, first move +to the record you wish to delete. Then, call <a href="#primeDelete">primeDelete</a>() to get +the pointer to the edit buffer. Finally, call <a href="#del">del</a>() to delete the +record from the database. Again, the values in the edit buffer +will be used to locate and delete the appropriate record. +<p> To insert a new record, call <a href="#primeInsert">primeInsert</a>() to get the pointer to +the edit buffer. Use this pointer to populate the edit buffer +with new values and then <a href="#insert">insert</a>() the record into the database. +<p> After calling insert(), update() or del(), the cursor is no longer +positioned on a valid record and can no longer be navigated +(<a href="ntqsqlquery.html#isValid">isValid</a>() return FALSE). The reason for this is that any changes +made to the database will not be visible until <a href="#select">select</a>() is called +to refresh the cursor. You can change this behavior by passing +FALSE to insert(), <a href="#update">update</a>() or del() which will prevent the cursor +from becoming invalid. The edits will still not be visible when +navigating the cursor until select() is called. +<p> TQSqlCursor contains virtual methods which allow editing behavior +to be customized by subclasses. This allows custom cursors to be +created that encapsulate the editing behavior of a database table +for an entire application. For example, a cursor can be customized +to always auto-number primary index fields, or provide fields with +suitable default values, when inserting new records. TQSqlCursor +generates SQL statements which are sent to the database engine; +you can control which fields are included in these statements +using <a href="#setGenerated">setGenerated</a>(). +<p> Note that TQSqlCursor does not inherit from <a href="ntqobject.html">TQObject</a>. This means +that you are responsible for destroying instances of this class +yourself. However if you create a TQSqlCursor and use it in a +<a href="ntqdatatable.html">TQDataTable</a>, <a href="ntqdatabrowser.html">TQDataBrowser</a> or a <a href="ntqdataview.html">TQDataView</a> these classes will +usually take ownership of the cursor and destroy it when they +don't need it anymore. The documentation for <a href="ntqdatatable.html">TQDataTable</a>, +<a href="ntqdatabrowser.html">TQDataBrowser</a> and <a href="ntqdataview.html">TQDataView</a> explicitly states which calls take +ownership of the cursor. +<p>See also <a href="database.html">Database Classes</a>. + +<hr><h2>Member Type Documentation</h2> +<h3 class=fn><a name="Mode-enum"></a>TQSqlCursor::Mode</h3> + +<p> This enum type describes how TQSqlCursor operates on records in the +database. +<ul> +<li><tt>TQSqlCursor::ReadOnly</tt> - the cursor can only SELECT records from the +database. +<li><tt>TQSqlCursor::Insert</tt> - the cursor can INSERT records into the database. +<li><tt>TQSqlCursor::Update</tt> - the cursor can UPDATE records in the database. +<li><tt>TQSqlCursor::Delete</tt> - the cursor can DELETE records from the database. +<li><tt>TQSqlCursor::Writable</tt> - the cursor can INSERT, UPDATE and DELETE records +in the database. +</ul> +<hr><h2>Member Function Documentation</h2> +<h3 class=fn><a name="TQSqlCursor"></a>TQSqlCursor::TQSqlCursor ( const <a href="ntqstring.html">TQString</a> & name = TQString::null, bool autopopulate = TRUE, <a href="ntqsqldatabase.html">TQSqlDatabase</a> * db = 0 ) +</h3> +Constructs a cursor on database <em>db</em> using table or view <em>name</em>. +<p> If <em>autopopulate</em> is TRUE (the default), the <em>name</em> of the +cursor must correspond to an existing table or view name in the +database so that field information can be automatically created. +If the table or view does not exist, the cursor will not be +functional. +<p> The cursor is created with an initial mode of TQSqlCursor::Writable +(meaning that records can be inserted, updated or deleted using +the cursor). If the cursor does not have a unique primary index, +update and deletes cannot be performed. +<p> Note that <em>autopopulate</em> refers to populating the cursor with +meta-data, e.g. the names of the table's fields, not with +retrieving data. The <a href="#select">select</a>() function is used to populate the +cursor with data. +<p> <p>See also <a href="#setName">setName</a>() and <a href="#setMode">setMode</a>(). + +<h3 class=fn><a name="TQSqlCursor-2"></a>TQSqlCursor::TQSqlCursor ( const <a href="ntqsqlcursor.html">TQSqlCursor</a> & other ) +</h3> +Constructs a copy of <em>other</em>. + +<h3 class=fn><a name="~TQSqlCursor"></a>TQSqlCursor::~TQSqlCursor () +</h3> +Destroys the object and frees any allocated resources. + +<h3 class=fn>void <a name="append"></a>TQSqlCursor::append ( const <a href="qsqlfieldinfo.html">TQSqlFieldInfo</a> & fieldInfo )<tt> [virtual]</tt> +</h3> +Append a copy of field <em>fieldInfo</em> to the end of the cursor. Note +that all references to the cursor edit buffer become invalidated. + +<h3 class=fn><a href="ntqvariant.html">TQVariant</a> <a name="calculateField"></a>TQSqlCursor::calculateField ( const <a href="ntqstring.html">TQString</a> & name )<tt> [virtual protected]</tt> +</h3> +Protected virtual function which is called whenever a field needs +to be calculated. If calculated fields are being used, derived +classes must reimplement this function and return the appropriate +value for field <em>name</em>. The default implementation returns an +invalid <a href="ntqvariant.html">TQVariant</a>. +<p> <p>See also <a href="#setCalculated">setCalculated</a>(). + +<p>Examples: <a href="sql.html#x2259">sql/overview/subclass3/main.cpp</a> and <a href="sql.html#x2263">sql/overview/subclass4/main.cpp</a>. +<h3 class=fn>bool <a name="canDelete"></a>TQSqlCursor::canDelete () const +</h3> +Returns TRUE if the cursor will perform deletes; otherwise returns +FALSE. +<p> <p>See also <a href="#setMode">setMode</a>(). + +<h3 class=fn>bool <a name="canInsert"></a>TQSqlCursor::canInsert () const +</h3> +Returns TRUE if the cursor will perform inserts; otherwise returns +FALSE. +<p> <p>See also <a href="#setMode">setMode</a>(). + +<h3 class=fn>bool <a name="canUpdate"></a>TQSqlCursor::canUpdate () const +</h3> +Returns TRUE if the cursor will perform updates; otherwise returns +FALSE. +<p> <p>See also <a href="#setMode">setMode</a>(). + +<h3 class=fn>void <a name="clear"></a>TQSqlCursor::clear ()<tt> [virtual]</tt> +</h3> +Removes all fields from the cursor. Note that all references to +the cursor edit buffer become invalidated. + +<p>Reimplemented from <a href="ntqsqlrecord.html#clear">TQSqlRecord</a>. +<h3 class=fn>int <a name="del"></a>TQSqlCursor::del ( bool invalidate = TRUE )<tt> [virtual]</tt> +</h3> +Deletes a record from the database using the cursor's primary +index and the contents of the cursor edit buffer. Returns the +number of records which were deleted. +For error information, use <a href="ntqsqlquery.html#lastError">lastError</a>(). +<p> Only records which meet the filter criteria specified by the +cursor's primary index are deleted. If the cursor does not contain +a primary index, no delete is performed and 0 is returned. If <em>invalidate</em> is TRUE (the default), the current cursor can no longer +be navigated. A new <a href="#select">select</a>() call must be made before you can move +to a valid record. For example: +<p> + +<pre> TQSqlCursor cur( "prices" ); + <a name="x2207"></a> cur.<a href="#select">select</a>( "id=999" ); + <a name="x2208"></a> if ( cur.<a href="ntqsqlquery.html#next">next</a>() ) { + <a name="x2206"></a> cur.<a href="#primeDelete">primeDelete</a>(); + <a name="x2205"></a> cur.<a href="#del">del</a>(); + } +</pre> +<p> In the above example, a cursor is created on the 'prices' table +and positioned to the record to be deleted. First <a href="#primeDelete">primeDelete</a>() is +called to populate the edit buffer with the current cursor values, +e.g. with an id of 999, and then <a href="#del">del</a>() is called to actually +delete the record from the database. Remember: all edit operations +(<a href="#insert">insert</a>(), <a href="#update">update</a>() and delete()) operate on the contents of the +cursor edit buffer and not on the contents of the cursor itself. +<p> <p>See also <a href="#primeDelete">primeDelete</a>(), <a href="#setMode">setMode</a>(), and <a href="ntqsqlquery.html#lastError">lastError</a>(). + +<p>Example: <a href="sql.html#x2205">sql/overview/delete/main.cpp</a>. +<h3 class=fn>int <a name="del-2"></a>TQSqlCursor::del ( const <a href="ntqstring.html">TQString</a> & filter, bool invalidate = TRUE )<tt> [virtual protected]</tt> +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Deletes the current cursor record from the database using the +filter <em>filter</em>. Only records which meet the filter criteria are +deleted. Returns the number of records which were deleted. If <em>invalidate</em> is TRUE (the default), the current cursor can no longer +be navigated. A new <a href="#select">select</a>() call must be made before you can move +to a valid record. For error information, use <a href="ntqsqlquery.html#lastError">lastError</a>(). +<p> The <em>filter</em> is an SQL <tt>WHERE</tt> clause, e.g. <tt>id=500</tt>. +<p> <p>See also <a href="#setMode">setMode</a>() and <a href="ntqsqlquery.html#lastError">lastError</a>(). + +<h3 class=fn><a href="ntqsqlrecord.html">TQSqlRecord</a> * <a name="editBuffer"></a>TQSqlCursor::editBuffer ( bool copy = FALSE )<tt> [virtual]</tt> +</h3> +Returns the current internal edit buffer. If <em>copy</em> is TRUE (the +default is FALSE), the current cursor field values are first +copied into the edit buffer. The edit buffer is valid as long as +the cursor remains valid. The cursor retains ownership of the +returned pointer, so it must not be deleted or modified. +<p> <p>See also <a href="#primeInsert">primeInsert</a>(), <a href="#primeUpdate">primeUpdate</a>(), and <a href="#primeDelete">primeDelete</a>(). + +<h3 class=fn><a href="ntqstring.html">TQString</a> <a name="filter"></a>TQSqlCursor::filter () const +</h3> +Returns the current filter, or an empty string if there is no +current filter. + +<h3 class=fn><a href="ntqsqlindex.html">TQSqlIndex</a> <a name="index"></a>TQSqlCursor::index ( const <a href="ntqstringlist.html">TQStringList</a> & fieldNames ) const<tt> [virtual]</tt> +</h3> +Returns an index composed of <em>fieldNames</em>, all in ASCending +order. Note that all field names must exist in the cursor, +otherwise an empty index is returned. +<p> <p>See also <a href="ntqsqlindex.html">TQSqlIndex</a>. + +<p>Examples: <a href="sql.html#x2188">sql/overview/extract/main.cpp</a>, <a href="sql.html#x2181">sql/overview/order1/main.cpp</a>, <a href="sql.html#x2184">sql/overview/order2/main.cpp</a>, and <a href="sql.html#x2241">sql/overview/table3/main.cpp</a>. +<h3 class=fn><a href="ntqsqlindex.html">TQSqlIndex</a> <a name="index-2"></a>TQSqlCursor::index ( const <a href="ntqstring.html">TQString</a> & fieldName ) const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Returns an index based on <em>fieldName</em>. + +<h3 class=fn><a href="ntqsqlindex.html">TQSqlIndex</a> <a name="index-3"></a>TQSqlCursor::index ( const char * fieldName ) const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Returns an index based on <em>fieldName</em>. + +<h3 class=fn>void <a name="insert"></a>TQSqlCursor::insert ( int pos, const <a href="qsqlfieldinfo.html">TQSqlFieldInfo</a> & fieldInfo )<tt> [virtual]</tt> +</h3> +Insert a copy of <em>fieldInfo</em> at position <em>pos</em>. If a field +already exists at <em>pos</em>, it is removed. Note that all references +to the cursor edit buffer become invalidated. + +<p>Examples: <a href="sql.html#x2194">sql/overview/insert/main.cpp</a> and <a href="ntqsqlcursor.html#x2446">sql/overview/insert2/main.cpp</a>. +<h3 class=fn>int <a name="insert-2"></a>TQSqlCursor::insert ( bool invalidate = TRUE )<tt> [virtual]</tt> +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Inserts the current contents of the cursor's edit record buffer +into the database, if the cursor allows inserts. Returns the +number of rows affected by the insert. For error information, use +<a href="ntqsqlquery.html#lastError">lastError</a>(). +<p> If <em>invalidate</em> is TRUE (the default), the cursor will no longer +be positioned on a valid record and can no longer be navigated. A +new <a href="#select">select</a>() call must be made before navigating to a valid +record. +<p> + +<pre> TQSqlCursor cur( "prices" ); + <a name="x2447"></a> <a href="ntqsqlrecord.html">TQSqlRecord</a> *buffer = cur.<a href="#primeInsert">primeInsert</a>(); + <a name="x2448"></a> buffer-><a href="ntqsqlrecord.html#setValue">setValue</a>( "id", 53981 ); + buffer-><a href="ntqsqlrecord.html#setValue">setValue</a>( "name", "Thingy" ); + buffer-><a href="ntqsqlrecord.html#setValue">setValue</a>( "price", 105.75 ); + <a name="x2446"></a> cur.<a href="#insert">insert</a>(); +</pre> +<p> In the above example, a cursor is created on the 'prices' table +and a pointer to the insert buffer is atquired using <a href="#primeInsert">primeInsert</a>(). +Each field's value is set to the desired value and then <a href="#insert">insert</a>() +is called to insert the data into the database. Remember: all edit +operations (insert(), <a href="#update">update</a>() and delete()) operate on the +contents of the cursor edit buffer and not on the contents of the +cursor itself. +<p> <p>See also <a href="#setMode">setMode</a>() and <a href="ntqsqlquery.html#lastError">lastError</a>(). + +<h3 class=fn>bool <a name="isCalculated"></a>TQSqlCursor::isCalculated ( const <a href="ntqstring.html">TQString</a> & name ) const +</h3> +Returns TRUE if the field <em>name</em> exists and is calculated; +otherwise returns FALSE. +<p> <p>See also <a href="#setCalculated">setCalculated</a>(). + +<h3 class=fn>bool <a name="isNull"></a>TQSqlCursor::isNull ( int i ) const +</h3> +Returns TRUE if the field <em>i</em> is NULL or if there is no field at +position <em>i</em>; otherwise returns FALSE. +<p> This is the same as calling <a href="ntqsqlrecord.html#isNull">TQSqlRecord::isNull</a>( <em>i</em> ) + +<h3 class=fn>bool <a name="isNull-2"></a>TQSqlCursor::isNull ( const <a href="ntqstring.html">TQString</a> & name ) const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Returns TRUE if the field called <em>name</em> is NULL or if there is no +field called <em>name</em>; otherwise returns FALSE. +<p> This is the same as calling <a href="ntqsqlrecord.html#isNull">TQSqlRecord::isNull</a>( <em>name</em> ) + +<h3 class=fn>bool <a name="isReadOnly"></a>TQSqlCursor::isReadOnly () const +</h3> +Returns TRUE if the cursor is read-only; otherwise returns FALSE. +The default is FALSE. Read-only cursors cannot be edited using +<a href="#insert">insert</a>(), <a href="#update">update</a>() or <a href="#del">del</a>(). +<p> <p>See also <a href="#setMode">setMode</a>(). + +<h3 class=fn>bool <a name="isTrimmed"></a>TQSqlCursor::isTrimmed ( const <a href="ntqstring.html">TQString</a> & name ) const +</h3> +Returns TRUE if the field <em>name</em> exists and is trimmed; otherwise +returns FALSE. +<p> When a trimmed field of type string or cstring is read from the +database any trailing (right-most) spaces are removed. +<p> <p>See also <a href="#setTrimmed">setTrimmed</a>(). + +<h3 class=fn>int <a name="mode"></a>TQSqlCursor::mode () const +</h3> +Returns the current cursor mode. +<p> <p>See also <a href="#setMode">setMode</a>(). + +<h3 class=fn><a href="ntqstring.html">TQString</a> <a name="name"></a>TQSqlCursor::name () const +</h3> +Returns the name of the cursor. + +<h3 class=fn><a href="ntqsqlcursor.html">TQSqlCursor</a> & <a name="operator-eq"></a>TQSqlCursor::operator= ( const <a href="ntqsqlcursor.html">TQSqlCursor</a> & other ) +</h3> +Sets the cursor equal to <em>other</em>. + +<h3 class=fn><a href="ntqsqlindex.html">TQSqlIndex</a> <a name="primaryIndex"></a>TQSqlCursor::primaryIndex ( bool setFromCursor = TRUE ) const<tt> [virtual]</tt> +</h3> +Returns the primary index associated with the cursor as defined in +the database, or an empty index if there is no primary index. If +<em>setFromCursor</em> is TRUE (the default), the index fields are +populated with the corresponding values in the cursor's current +record. + +<h3 class=fn><a href="ntqsqlrecord.html">TQSqlRecord</a> * <a name="primeDelete"></a>TQSqlCursor::primeDelete ()<tt> [virtual]</tt> +</h3> +This function primes the edit buffer's field values for delete and +returns the edit buffer. The default implementation copies the +field values from the current cursor record into the edit buffer +(therefore, this function is equivalent to calling <a href="#editBuffer">editBuffer</a>( +TRUE ) ). The cursor retains ownership of the returned pointer, so +it must not be deleted or modified. +<p> <p>See also <a href="#editBuffer">editBuffer</a>() and <a href="#del">del</a>(). + +<p>Example: <a href="sql.html#x2206">sql/overview/delete/main.cpp</a>. +<h3 class=fn><a href="ntqsqlrecord.html">TQSqlRecord</a> * <a name="primeInsert"></a>TQSqlCursor::primeInsert ()<tt> [virtual]</tt> +</h3> +This function primes the edit buffer's field values for insert and +returns the edit buffer. The default implementation clears all +field values in the edit buffer. The cursor retains ownership of +the returned pointer, so it must not be deleted or modified. +<p> <p>See also <a href="#editBuffer">editBuffer</a>() and <a href="#insert">insert</a>(). + +<p>Examples: <a href="sql.html#x2195">sql/overview/insert/main.cpp</a>, <a href="ntqsqlcursor.html#x2447">sql/overview/insert2/main.cpp</a>, <a href="sql.html#x2267">sql/overview/subclass5/main.cpp</a>, and <a href="sqltable-example.html#x2453">sql/sqltable/main.cpp</a>. +<h3 class=fn><a href="ntqsqlrecord.html">TQSqlRecord</a> * <a name="primeUpdate"></a>TQSqlCursor::primeUpdate ()<tt> [virtual]</tt> +</h3> +This function primes the edit buffer's field values for update and +returns the edit buffer. The default implementation copies the +field values from the current cursor record into the edit buffer +(therefore, this function is equivalent to calling <a href="#editBuffer">editBuffer</a>( +TRUE ) ). The cursor retains ownership of the returned pointer, so +it must not be deleted or modified. +<p> <p>See also <a href="#editBuffer">editBuffer</a>() and <a href="#update">update</a>(). + +<p>Examples: <a href="sql.html#x2236">sql/overview/custom1/main.cpp</a>, <a href="sql.html#x2223">sql/overview/form1/main.cpp</a>, and <a href="sql.html#x2199">sql/overview/update/main.cpp</a>. +<h3 class=fn>void <a name="remove"></a>TQSqlCursor::remove ( int pos )<tt> [virtual]</tt> +</h3> +Removes the field at <em>pos</em>. If <em>pos</em> does not exist, nothing +happens. Note that all references to the cursor edit buffer become +invalidated. + +<p>Reimplemented from <a href="ntqsqlrecord.html#remove">TQSqlRecord</a>. +<h3 class=fn>bool <a name="select"></a>TQSqlCursor::select ( const <a href="ntqstring.html">TQString</a> & filter, const <a href="ntqsqlindex.html">TQSqlIndex</a> & sort = TQSqlIndex ( ) )<tt> [virtual]</tt> +</h3> +Selects all fields in the cursor from the database matching the +filter criteria <em>filter</em>. The data is returned in the order +specified by the index <em>sort</em>. Returns TRUE if the data was +successfully selected; otherwise returns FALSE. +<p> The <em>filter</em> is a string containing a SQL <tt>WHERE</tt> clause but +without the 'WHERE' keyword. The cursor is initially positioned at +an invalid row after this function is called. To move to a valid +row, use <a href="ntqsqlquery.html#seek">seek</a>(), <a href="ntqsqlquery.html#first">first</a>(), <a href="ntqsqlquery.html#last">last</a>(), <a href="ntqsqlquery.html#prev">prev</a>() or <a href="ntqsqlquery.html#next">next</a>(). +<p> Example: +<pre> + TQSqlCursor cur( "Employee" ); // Use the Employee table or view + cur.<a href="#select">select</a>( "deptno=10" ); // select all records in department 10 + while( cur.<a href="ntqsqlquery.html#next">next</a>() ) { + ... // process data + } + ... + // select records in other departments, ordered by department number + cur.<a href="#select">select</a>( "deptno>10", cur.<a href="#index">index</a>( "deptno" ) ); + ... + </pre> + +<p> The filter will apply to any subsequent <a href="#select">select</a>() calls that do not +explicitly specify another filter. Similarly the sort will apply +to any subsequent select() calls that do not explicitly specify +another sort. +<p> <pre> + TQSqlCursor cur( "Employee" ); + cur.<a href="#select">select</a>( "deptno=10" ); // select all records in department 10 + while( cur.<a href="ntqsqlquery.html#next">next</a>() ) { + ... // process data + } + ... + cur.<a href="#select">select</a>(); // re-selects all records in department 10 + ... + </pre> + +<p> +<p>Examples: <a href="sql.html#x2207">sql/overview/delete/main.cpp</a>, <a href="sql.html#x2189">sql/overview/extract/main.cpp</a>, <a href="sql.html#x2182">sql/overview/order1/main.cpp</a>, <a href="sql.html#x2185">sql/overview/order2/main.cpp</a>, <a href="sql.html#x2178">sql/overview/retrieve2/main.cpp</a>, <a href="sql.html#x2242">sql/overview/table3/main.cpp</a>, and <a href="sql.html#x2200">sql/overview/update/main.cpp</a>. +<h3 class=fn>bool <a name="select-2"></a>TQSqlCursor::select () +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Selects all fields in the cursor from the database. The rows are +returned in the order specified by the last call to <a href="#setSort">setSort</a>() or +the last call to <a href="#select">select</a>() that specified a sort, whichever is the +most recent. If there is no current sort, the order in which the +rows are returned is undefined. The records are filtered according +to the filter specified by the last call to <a href="#setFilter">setFilter</a>() or the +last call to select() that specified a filter, whichever is the +most recent. If there is no current filter, all records are +returned. The cursor is initially positioned at an invalid row. To +move to a valid row, use <a href="ntqsqlquery.html#seek">seek</a>(), <a href="ntqsqlquery.html#first">first</a>(), <a href="ntqsqlquery.html#last">last</a>(), <a href="ntqsqlquery.html#prev">prev</a>() or +<a href="ntqsqlquery.html#next">next</a>(). +<p> <p>See also <a href="#setSort">setSort</a>() and <a href="#setFilter">setFilter</a>(). + +<h3 class=fn>bool <a name="select-3"></a>TQSqlCursor::select ( const <a href="ntqsqlindex.html">TQSqlIndex</a> & sort ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Selects all fields in the cursor from the database. The data is +returned in the order specified by the index <em>sort</em>. The records +are filtered according to the filter specified by the last call to +<a href="#setFilter">setFilter</a>() or the last call to <a href="#select">select</a>() that specified a filter, +whichever is the most recent. The cursor is initially positioned +at an invalid row. To move to a valid row, use <a href="ntqsqlquery.html#seek">seek</a>(), <a href="ntqsqlquery.html#first">first</a>(), +<a href="ntqsqlquery.html#last">last</a>(), <a href="ntqsqlquery.html#prev">prev</a>() or <a href="ntqsqlquery.html#next">next</a>(). + +<h3 class=fn>bool <a name="select-4"></a>TQSqlCursor::select ( const <a href="ntqsqlindex.html">TQSqlIndex</a> & filter, const <a href="ntqsqlindex.html">TQSqlIndex</a> & sort ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Selects all fields in the cursor matching the filter index <em>filter</em>. The data is returned in the order specified by the index +<em>sort</em>. The <em>filter</em> index works by constructing a WHERE clause +using the names of the fields from the <em>filter</em> and their values +from the current cursor record. The cursor is initially positioned +at an invalid row. To move to a valid row, use <a href="ntqsqlquery.html#seek">seek</a>(), <a href="ntqsqlquery.html#first">first</a>(), +<a href="ntqsqlquery.html#last">last</a>(), <a href="ntqsqlquery.html#prev">prev</a>() or <a href="ntqsqlquery.html#next">next</a>(). This function is useful, for example, +for retrieving data based upon a table's primary index: +<p> <pre> + TQSqlCursor cur( "Employee" ); + <a href="ntqsqlindex.html">TQSqlIndex</a> pk = cur.<a href="#primaryIndex">primaryIndex</a>(); + cur.<a href="ntqsqlrecord.html#setValue">setValue</a>( "id", 10 ); + cur.<a href="#select">select</a>( pk, pk ); // generates "SELECT ... FROM Employee WHERE id=10 ORDER BY id" + ... + </pre> + +<p> In this example the <a href="ntqsqlindex.html">TQSqlIndex</a>, pk, is used for two different +purposes. When used as the filter (first) argument, the field +names it contains are used to construct the WHERE clause, each set +to the current cursor value, <tt>WHERE id=10</tt>, in this case. When +used as the sort (second) argument the field names it contains are +used for the ORDER BY clause, <tt>ORDER BY id</tt> in this example. + +<h3 class=fn>void <a name="setCalculated"></a>TQSqlCursor::setCalculated ( const <a href="ntqstring.html">TQString</a> & name, bool calculated )<tt> [virtual]</tt> +</h3> +Sets field <em>name</em> to <em>calculated</em>. If the field <em>name</em> does not +exist, nothing happens. The value of a calculated field is set by +the <a href="#calculateField">calculateField</a>() virtual function which you must reimplement +(or the field value will be an invalid <a href="ntqvariant.html">TQVariant</a>). Calculated +fields do not appear in generated SQL statements sent to the +database. +<p> <p>See also <a href="#calculateField">calculateField</a>() and <a href="ntqsqlrecord.html#setGenerated">TQSqlRecord::setGenerated</a>(). + +<h3 class=fn>void <a name="setFilter"></a>TQSqlCursor::setFilter ( const <a href="ntqstring.html">TQString</a> & filter )<tt> [virtual]</tt> +</h3> +Sets the current filter to <em>filter</em>. Note that no new records are +selected. To select new records, use <a href="#select">select</a>(). The <em>filter</em> will +apply to any subsequent select() calls that do not explicitly +specify a filter. +<p> The filter is a SQL <tt>WHERE</tt> clause without the keyword 'WHERE', +e.g. <tt>name='Dave'</tt> which will be processed by the DBMS. + +<h3 class=fn>void <a name="setGenerated"></a>TQSqlCursor::setGenerated ( const <a href="ntqstring.html">TQString</a> & name, bool generated )<tt> [virtual]</tt> +</h3> +Sets the generated flag for the field <em>name</em> to <em>generated</em>. If +the field does not exist, nothing happens. Only fields that have +<em>generated</em> set to TRUE are included in the SQL that is +generated by <a href="#insert">insert</a>(), <a href="#update">update</a>() or <a href="#del">del</a>(). +<p> <p>See also <a href="ntqsqlrecord.html#isGenerated">isGenerated</a>(). + +<p>Reimplemented from <a href="ntqsqlrecord.html#setGenerated">TQSqlRecord</a>. +<h3 class=fn>void <a name="setGenerated-2"></a>TQSqlCursor::setGenerated ( int i, bool generated )<tt> [virtual]</tt> +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Sets the generated flag for the field <em>i</em> to <em>generated</em>. +<p> <p>See also <a href="ntqsqlrecord.html#isGenerated">isGenerated</a>(). + +<p>Reimplemented from <a href="ntqsqlrecord.html#setGenerated-2">TQSqlRecord</a>. +<h3 class=fn>void <a name="setMode"></a>TQSqlCursor::setMode ( int mode )<tt> [virtual]</tt> +</h3> +Sets the cursor mode to <em>mode</em>. This value can be an OR'ed +combination of <a href="#Mode-enum">TQSqlCursor::Mode</a> values. The default mode for a +cursor is <a href="#Mode-enum">TQSqlCursor::Writable</a>. +<p> <pre> + TQSqlCursor cur( "Employee" ); + cur.<a href="#setMode">setMode</a>( TQSqlCursor::<a href="#Mode-enum">Writable</a> ); // allow insert/update/delete + ... + cur.<a href="#setMode">setMode</a>( TQSqlCursor::<a href="#Mode-enum">Insert</a> | TQSqlCursor::<a href="#Mode-enum">Update</a> ); // allow inserts and updates only + ... + cur.<a href="#setMode">setMode</a>( TQSqlCursor::<a href="#Mode-enum">ReadOnly</a> ); // no inserts/updates/deletes allowed + + </pre> + + +<h3 class=fn>void <a name="setName"></a>TQSqlCursor::setName ( const <a href="ntqstring.html">TQString</a> & name, bool autopopulate = TRUE )<tt> [virtual]</tt> +</h3> +Sets the name of the cursor to <em>name</em>. If <em>autopopulate</em> is TRUE +(the default), the <em>name</em> must correspond to a valid table or +view name in the database. Also, note that all references to the +cursor edit buffer become invalidated when fields are +auto-populated. See the TQSqlCursor constructor documentation for +more information. + +<h3 class=fn>void <a name="setPrimaryIndex"></a>TQSqlCursor::setPrimaryIndex ( const <a href="ntqsqlindex.html">TQSqlIndex</a> & idx )<tt> [virtual]</tt> +</h3> +Sets the primary index associated with the cursor to the index <em>idx</em>. Note that this index must contain a field or set of fields +which identify a unique record within the underlying database +table or view so that <a href="#update">update</a>() and <a href="#del">del</a>() will execute as expected. +<p> <p>See also <a href="#update">update</a>() and <a href="#del">del</a>(). + +<h3 class=fn>void <a name="setSort"></a>TQSqlCursor::setSort ( const <a href="ntqsqlindex.html">TQSqlIndex</a> & sort )<tt> [virtual]</tt> +</h3> +Sets the current sort to <em>sort</em>. Note that no new records are +selected. To select new records, use <a href="#select">select</a>(). The <em>sort</em> will +apply to any subsequent select() calls that do not explicitly +specify a sort. + +<h3 class=fn>void <a name="setTrimmed"></a>TQSqlCursor::setTrimmed ( const <a href="ntqstring.html">TQString</a> & name, bool trim )<tt> [virtual]</tt> +</h3> +Sets field <em>name</em>'s trimmed status to <em>trim</em>. If the field <em>name</em> does not exist, nothing happens. +<p> When a trimmed field of type string or cstring is read from the +database any trailing (right-most) spaces are removed. +<p> <p>See also <a href="#isTrimmed">isTrimmed</a>() and <a href="ntqvariant.html">TQVariant</a>. + +<h3 class=fn><a href="ntqsqlindex.html">TQSqlIndex</a> <a name="sort"></a>TQSqlCursor::sort () const +</h3> +Returns the current sort, or an empty index if there is no current +sort. + +<h3 class=fn><a href="ntqstring.html">TQString</a> <a name="toString"></a>TQSqlCursor::toString ( <a href="ntqsqlrecord.html">TQSqlRecord</a> * rec, const <a href="ntqstring.html">TQString</a> & prefix, const <a href="ntqstring.html">TQString</a> & fieldSep, const <a href="ntqstring.html">TQString</a> & sep ) const<tt> [virtual protected]</tt> +</h3> +Returns a formatted string composed of all the fields in <em>rec</em>. +Each field is composed of the <em>prefix</em> (e.g. table or view name), +".", the field name, the <em>fieldSep</em> and the field value. If the +<em>prefix</em> is empty then each field will begin with the field name. +The fields are then joined together separated by <em>sep</em>. Fields +where <a href="ntqsqlrecord.html#isGenerated">isGenerated</a>() returns FALSE are not included. This function +is useful for generating SQL statements. + +<h3 class=fn><a href="ntqstring.html">TQString</a> <a name="toString-3"></a>TQSqlCursor::toString ( const <a href="ntqstring.html">TQString</a> & prefix, <a href="ntqsqlfield.html">TQSqlField</a> * field, const <a href="ntqstring.html">TQString</a> & fieldSep ) const<tt> [virtual protected]</tt> +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Returns a formatted string composed of the <em>prefix</em> (e.g. table +or view name), ".", the <em>field</em> name, the <em>fieldSep</em> and the +field value. If the <em>prefix</em> is empty then the string will begin +with the <em>field</em> name. This function is useful for generating SQL +statements. + +<h3 class=fn><a href="ntqstring.html">TQString</a> <a name="toString-4"></a>TQSqlCursor::toString ( const <a href="ntqsqlindex.html">TQSqlIndex</a> & i, <a href="ntqsqlrecord.html">TQSqlRecord</a> * rec, const <a href="ntqstring.html">TQString</a> & prefix, const <a href="ntqstring.html">TQString</a> & fieldSep, const <a href="ntqstring.html">TQString</a> & sep ) const<tt> [virtual protected]</tt> +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Returns a formatted string composed of all the fields in the index +<em>i</em>. Each field is composed of the <em>prefix</em> (e.g. table or view +name), ".", the field name, the <em>fieldSep</em> and the field value. +If the <em>prefix</em> is empty then each field will begin with the field +name. The field values are taken from <em>rec</em>. The fields are then +joined together separated by <em>sep</em>. Fields where <a href="ntqsqlrecord.html#isGenerated">isGenerated</a>() +returns FALSE are ignored. This function is useful for generating +SQL statements. + +<h3 class=fn>int <a name="update"></a>TQSqlCursor::update ( bool invalidate = TRUE )<tt> [virtual]</tt> +</h3> +Updates the database with the current contents of the edit buffer. +Returns the number of records which were updated. +For error information, use <a href="ntqsqlquery.html#lastError">lastError</a>(). +<p> Only records which meet the filter criteria specified by the +cursor's primary index are updated. If the cursor does not contain +a primary index, no update is performed and 0 is returned. +<p> If <em>invalidate</em> is TRUE (the default), the current cursor can no +longer be navigated. A new <a href="#select">select</a>() call must be made before you +can move to a valid record. For example: +<p> + +<pre> TQSqlCursor cur( "prices" ); + <a name="x2200"></a> cur.<a href="#select">select</a>( "id=202" ); + if ( cur.<a href="ntqsqlquery.html#next">next</a>() ) { + <a name="x2199"></a> <a href="ntqsqlrecord.html">TQSqlRecord</a> *buffer = cur.<a href="#primeUpdate">primeUpdate</a>(); + <a name="x2204"></a> double price = buffer-><a href="ntqsqlrecord.html#value">value</a>( "price" ).toDouble(); + double newprice = price * 1.05; + <a name="x2203"></a> buffer-><a href="ntqsqlrecord.html#setValue">setValue</a>( "price", newprice ); + <a name="x2201"></a> cur.<a href="#update">update</a>(); + } +</pre> +<p> In the above example, a cursor is created on the 'prices' table +and is positioned on the record to be updated. Then a pointer to +the cursor's edit buffer is actquired using <a href="#primeUpdate">primeUpdate</a>(). A new +value is calculated and placed into the edit buffer with the +<a href="ntqsqlrecord.html#setValue">setValue</a>() call. Finally, an <a href="#update">update</a>() call is made on the cursor +which uses the tables's primary index to update the record in the +database with the contents of the cursor's edit buffer. Remember: +all edit operations (<a href="#insert">insert</a>(), update() and delete()) operate on +the contents of the cursor edit buffer and not on the contents of +the cursor itself. +<p> Note that if the primary index does not uniquely distinguish +records the database may be changed into an inconsistent state. +<p> <p>See also <a href="#setMode">setMode</a>() and <a href="ntqsqlquery.html#lastError">lastError</a>(). + +<p>Example: <a href="sql.html#x2201">sql/overview/update/main.cpp</a>. +<h3 class=fn>int <a name="update-2"></a>TQSqlCursor::update ( const <a href="ntqstring.html">TQString</a> & filter, bool invalidate = TRUE )<tt> [virtual protected]</tt> +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Updates the database with the current contents of the cursor edit +buffer using the specified <em>filter</em>. Returns the number of +records which were updated. +For error information, use <a href="ntqsqlquery.html#lastError">lastError</a>(). +<p> Only records which meet the filter criteria are updated, otherwise +all records in the table are updated. +<p> If <em>invalidate</em> is TRUE (the default), the cursor can no longer +be navigated. A new <a href="#select">select</a>() call must be made before you can move +to a valid record. +<p> <p>See also <a href="#primeUpdate">primeUpdate</a>(), <a href="#setMode">setMode</a>(), and <a href="ntqsqlquery.html#lastError">lastError</a>(). + +<!-- eof --> +<hr><p> +This file is part of the <a href="index.html">TQt toolkit</a>. +Copyright © 1995-2007 +<a href="http://www.trolltech.com/">Trolltech</a>. 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