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/***************************************************************************
* kexidbcursor.h
* This file is part of the KDE project
* copyright (C)2004-2005 by Sebastian Sauer ([email protected])
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
* You should have received a copy of the GNU Library General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
***************************************************************************/
#ifndef KROSS_KEXIDB_KEXIDBCURSOR_H
#define KROSS_KEXIDB_KEXIDBCURSOR_H
#include <qstring.h>
#include <api/object.h>
#include <api/variant.h>
#include <api/list.h>
#include <api/class.h>
#include <kexidb/cursor.h>
#include <kexidb/roweditbuffer.h>
namespace Kross { namespace KexiDB {
// Forward declaration.
class KexiDBConnection;
/**
* The cursor provides a control structure for the successive traversal
* of records in a result set as returned e.g. by a query.
*
* Example (in Python) that shows how to iterate over the result of a query;
* @code
* # Once we have a KexiDBConnection object we are able to execute a query string and get a cursor as result.
* cursor = connection.executeQueryString("SELECT * from emp")
* # Let's check if the query was successfully.
* if not cursor: raise("Query failed")
* # Walk through all items in the table.
* while(not cursor.eof()):
* # Iterate over the fields the record has.
* for i in range( cursor.fieldCount() ):
* # Print some information.
* print "%s %s %s" % (cursor.at(), i, cursor.value(i))
* # and move on to the next record.
* cursor.moveNext()
* @endcode
*
* Example (in Python) that shows how to use a cursor to strip
* all whitespaces at the beginning and the end from the values
* in a table;
* @code
* import krosskexidb
* drivermanager = krosskexidb.DriverManager()
* connectiondata = drivermanager.createConnectionDataByFile("/home/me/kexiprojectfile.kexi")
* driver = drivermanager.driver( connectiondata.driverName() )
* connection = driver.createConnection(connectiondata)
* if not connection.connect(): raise "Failed to connect"
* if not connection.useDatabase( connectiondata.databaseName() ):
* if not connection.useDatabase( connectiondata.fileName() ):
* raise "Failed to use database"
*
* table = connection.tableSchema("emp")
* query = table.query()
* cursor = connection.executeQuerySchema(query)
* if not cursor: raise("Query failed")
* while(not cursor.eof()):
* for i in range( cursor.fieldCount() ):
* v = str( cursor.value(i) )
* if v.startswith(' ') or v.endswith(' '):
* cursor.setValue(i, v.strip())
* cursor.moveNext()
* if not cursor.save(): raise "Failed to save changes"
* @endcode
*/
class KexiDBCursor : public Kross::Api::Class<KexiDBCursor>
{
public:
KexiDBCursor(::KexiDB::Cursor* cursor);
virtual ~KexiDBCursor();
virtual const QString getClassName() const;
private:
/** Opens the cursor. */
bool open();
/** Returns true if the cursor is opened else false. */
bool isOpened();
/** Closes and then opens again the same cursor. */
bool reopen();
/** Closes previously opened cursor. */
bool close();
/** Moves current position to the first record and retrieves it. */
bool moveFirst();
/** Moves current position to the last record and retrieves it. */
bool moveLast();
/** Moves current position to the previous record and retrieves it. */
bool movePrev();
/** Moves current position to the next record and retrieves it. */
bool moveNext();
/** Returns true if current position is before first record. */
bool bof();
/** Returns true if current position is after last record. */
bool eof();
/** Returns current internal position of the cursor's query. Records
are numbered from 0; the value -1 means that the cursor does not
point to a valid record. */
Q_LLONG at();
/** Returns the number of fields available for this cursor. */
uint fieldCount();
/** Returns the value stored in the passed column number (counting from 0). */
QVariant value(uint index);
/** Set the value for the field defined with index. The new value is buffered
and does not got written as long as save() is not called. */
bool setValue(uint index, QVariant value);
/** Save any changes done with setValue(). You should call this only once at
the end of all value/setValue iterations cause the cursor is closed once
the changes got saved successfully. */
bool save();
private:
::KexiDB::Cursor* m_cursor;
class Record {
public:
::KexiDB::RowData rowdata;
::KexiDB::RowEditBuffer* buffer;
Record(::KexiDB::Cursor* cursor)
: buffer( new ::KexiDB::RowEditBuffer(true) )
{
cursor->storeCurrentRow(rowdata);
}
~Record()
{
delete buffer;
}
};
QMap<Q_LLONG, Record*> m_modifiedrecords;
void clearBuffers();
};
}}
#endif
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