qx::QxSoftDelete : soft delete (or logical delete) behavior to update a row into database (flag it as deleted) instead of delete it from database More...

#include <QxSoftDelete.h>

Public Types
enum	mode { mode_flag, mode_date_time }
Public Member Functions
	QxSoftDelete ()
	QxSoftDelete (const QString &sColumn)
	QxSoftDelete (const QString &sColumn, mode eMode)
	~QxSoftDelete ()
QString	getTableName () const
QString	getColumnName () const
QString	getSqlQueryToFetch () const
QString	getSqlQueryToUpdate () const
QString	getSqlQueryToCreateTable () const
mode	getMode () const
void	setTableName (const QString &sTable)
void	setColumnName (const QString &sColumn)
void	setSqlQueryToFetch (const QString &s)
void	setSqlQueryToUpdate (const QString &s)
void	setSqlQueryToCreateTable (const QString &s)
void	setMode (mode eMode)
bool	isEmpty () const
QString	buildSqlTablePointName (const QString &sTable=QString()) const
QString	buildSqlQueryToFetch (const QString &sTable=QString()) const
QString	buildSqlQueryToUpdate () const
QString	buildSqlQueryToCreateTable () const
Private Attributes
QString	m_sTable
	Table name where soft delete behavior is applied.
QString	m_sColumn
	Column name to store soft delete information.
QString	m_sSqlQueryToFetch
	Overrided user SQL query to fetch an item, if empty QxOrm library builds a default SQL query.
QString	m_sSqlQueryToUpdate
	Overrided user SQL query to update an item, if empty QxOrm library builds a default SQL query.
QString	m_sSqlQueryToCreateTable
	Overrided user SQL query to create table, if empty QxOrm library builds a default SQL query.
mode	m_eMode
	Soft delete mode : 'mode_flag' with a boolean column, 'mode_date_time' with a date-time column containing deletion date-time.

Detailed Description

qx::QxSoftDelete : soft delete (or logical delete) behavior to update a row into database (flag it as deleted) instead of delete it from database

A soft delete doesn't remove rows from database (this is not a physical delete) : a new column is added to the table definition to flag a row as deleted or not. This column can contain a boolean (1 means row deleted, 0 or NULL means row not deleted), or can contain deletion date-time (if empty or NULL, row is not deleted). So you can reactivate a deleted row by setting NULL or empty value into database.

To define a soft delete behavior with QxOrm library, you have to use the class qx::QxSoftDelete in function mapping by class qx::register_class<T>. Here is an example with the class Bar containing 2 properties m_id and m_desc :

namespace qx {
template <> void register_class(QxClass<Bar> & t)
{
   t.setSoftDelete(qx::QxSoftDelete("deleted_at"));

   t.id(& Bar::m_id, "id");
   t.data(& Bar::m_desc, "desc");
}}

SQL queries builded by QxOrm library will take into account this soft delete parameter to add conditions (don't fetch deleted item, don't delete physically a row, etc.). For example, if you execute this code with the class Bar :

Bar_ptr pBar; pBar.reset(new Bar());
pBar->setId(5);
QSqlError daoError = qx::dao::delete_by_id(pBar);     qAssert(! daoError.isValid());
qx_bool bDaoExist = qx::dao::exist(pBar);             qAssert(! bDaoExist);
daoError = qx::dao::delete_all<Bar>();                qAssert(! daoError.isValid());
long lBarCount = qx::dao::count<Bar>();               qAssert(lBarCount == 0);
daoError = qx::dao::destroy_all<Bar>();               qAssert(! daoError.isValid());

You will obtain following output trace :

[QxOrm] sql query (93 ms) : UPDATE Bar SET deleted_at = '20110617115148615' WHERE id = :id
[QxOrm] sql query (0 ms) : SELECT Bar.id AS Bar_id_0, Bar.deleted_at FROM Bar WHERE Bar.id = :id AND (Bar.deleted_at IS NULL OR Bar.deleted_at = '')
[QxOrm] sql query (78 ms) : UPDATE Bar SET deleted_at = '20110617115148724'
[QxOrm] sql query (0 ms) : SELECT COUNT(*) FROM Bar WHERE (Bar.deleted_at IS NULL OR Bar.deleted_at = '')
[QxOrm] sql query (110 ms) : DELETE FROM Bar

Note : To delete physically a row from database, you have to use followings functions : qx::dao::destroy_by_id() and qx::dao::destroy_all().

Other note : it is recommended to define into database an index on column deleted_at to optimize execution of SQL queries.

Definition at line 96 of file QxSoftDelete.h.

Member Enumeration Documentation

enum qx::QxSoftDelete::mode

Enumerator:

mode_flag
mode_date_time

Definition at line 101 of file QxSoftDelete.h.

Constructor & Destructor Documentation

qx::QxSoftDelete::QxSoftDelete ( ) [inline]

Definition at line 114 of file QxSoftDelete.h.

qx::QxSoftDelete::QxSoftDelete ( const QString & sColumn ) [inline]

Definition at line 115 of file QxSoftDelete.h.

qx::QxSoftDelete::QxSoftDelete	(	const QString &	sColumn,
		mode	eMode
	)		`[inline]`

Definition at line 116 of file QxSoftDelete.h.

qx::QxSoftDelete::~QxSoftDelete ( ) [inline]

Definition at line 117 of file QxSoftDelete.h.

Member Function Documentation

QString qx::QxSoftDelete::buildSqlQueryToCreateTable ( ) const [inline]

Definition at line 160 of file QxSoftDelete.h.

QString qx::QxSoftDelete::buildSqlQueryToFetch ( const QString & sTable = QString() ) const [inline]

Definition at line 141 of file QxSoftDelete.h.

QString qx::QxSoftDelete::buildSqlQueryToUpdate ( ) const [inline]

Definition at line 151 of file QxSoftDelete.h.

QString qx::QxSoftDelete::buildSqlTablePointName ( const QString & sTable = QString() ) const [inline]

Definition at line 135 of file QxSoftDelete.h.

QString qx::QxSoftDelete::getColumnName ( ) const [inline]

Definition at line 120 of file QxSoftDelete.h.

mode qx::QxSoftDelete::getMode ( ) const [inline]

Definition at line 124 of file QxSoftDelete.h.

QString qx::QxSoftDelete::getSqlQueryToCreateTable ( ) const [inline]

Definition at line 123 of file QxSoftDelete.h.

QString qx::QxSoftDelete::getSqlQueryToFetch ( ) const [inline]

Definition at line 121 of file QxSoftDelete.h.

QString qx::QxSoftDelete::getSqlQueryToUpdate ( ) const [inline]

Definition at line 122 of file QxSoftDelete.h.

QString qx::QxSoftDelete::getTableName ( ) const [inline]

Definition at line 119 of file QxSoftDelete.h.

bool qx::QxSoftDelete::isEmpty ( ) const [inline]

Definition at line 133 of file QxSoftDelete.h.

void qx::QxSoftDelete::setColumnName ( const QString & sColumn ) [inline]

Definition at line 127 of file QxSoftDelete.h.

void qx::QxSoftDelete::setMode ( mode eMode ) [inline]

Definition at line 131 of file QxSoftDelete.h.

void qx::QxSoftDelete::setSqlQueryToCreateTable ( const QString & s ) [inline]

Definition at line 130 of file QxSoftDelete.h.

void qx::QxSoftDelete::setSqlQueryToFetch ( const QString & s ) [inline]

Definition at line 128 of file QxSoftDelete.h.

void qx::QxSoftDelete::setSqlQueryToUpdate ( const QString & s ) [inline]

Definition at line 129 of file QxSoftDelete.h.

void qx::QxSoftDelete::setTableName ( const QString & sTable ) [inline]

Definition at line 126 of file QxSoftDelete.h.

Member Data Documentation

mode qx::QxSoftDelete::m_eMode [private]

Soft delete mode : 'mode_flag' with a boolean column, 'mode_date_time' with a date-time column containing deletion date-time.

Definition at line 110 of file QxSoftDelete.h.

QString qx::QxSoftDelete::m_sColumn [private]

Column name to store soft delete information.

Definition at line 106 of file QxSoftDelete.h.

QString qx::QxSoftDelete::m_sSqlQueryToCreateTable [private]

Overrided user SQL query to create table, if empty QxOrm library builds a default SQL query.

Definition at line 109 of file QxSoftDelete.h.

QString qx::QxSoftDelete::m_sSqlQueryToFetch [private]

Overrided user SQL query to fetch an item, if empty QxOrm library builds a default SQL query.

Definition at line 107 of file QxSoftDelete.h.

QString qx::QxSoftDelete::m_sSqlQueryToUpdate [private]

Overrided user SQL query to update an item, if empty QxOrm library builds a default SQL query.

Definition at line 108 of file QxSoftDelete.h.

QString qx::QxSoftDelete::m_sTable [private]

Table name where soft delete behavior is applied.

Definition at line 105 of file QxSoftDelete.h.

The documentation for this class was generated from the following file:

D:/Dvlp/_Perso/QxOrm/include/QxDao/QxSoftDelete.h

Public Types

Public Member Functions

Private Attributes

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation