QSqlIndex Class

The QSqlIndex class provides functions to manipulate and describe database indexes. 更多...

頭: #include <QSqlIndex>
qmake: QT += sql
繼承: QSqlRecord

公共函數

QSqlIndex (const QString & cursorname = QString(), const QString & name = QString())
QSqlIndex (const QSqlIndex & other )
~QSqlIndex ()
void append (const QSqlField & field )
void append (const QSqlField & field , bool desc )
QString cursorName () const
bool isDescending (int i ) const
QString name () const
void setCursorName (const QString & cursorName )
void setDescending (int i , bool desc )
void setName (const QString & name )
QSqlIndex & operator= (const QSqlIndex & other )

詳細描述

The QSqlIndex class provides functions to manipulate and describe database indexes.

An index refers to a single table or view in a database. Information about the fields that comprise the index can be used to generate SQL statements.

成員函數文檔編製

QSqlIndex:: QSqlIndex (const QString & cursorname = QString(), const QString & name = QString())

Constructs an empty index using the cursor name cursorname and index name name .

QSqlIndex:: QSqlIndex (const QSqlIndex & other )

構造副本為 other .

QSqlIndex:: ~QSqlIndex ()

銷毀對象並釋放任何分配資源。

void QSqlIndex:: append (const QSqlField & field )

Appends the field field to the list of indexed fields. The field is appended with an ascending sort order.

void QSqlIndex:: append (const QSqlField & field , bool desc )

這是重載函數。

Appends the field field to the list of indexed fields. The field is appended with an ascending sort order, unless desc 為 true。

QString QSqlIndex:: cursorName () const

Returns the name of the cursor which the index is associated with.

另請參閱 setCursorName ().

bool QSqlIndex:: isDescending ( int i ) const

返迴 true if field i in the index is sorted in descending order; otherwise returns false .

QString QSqlIndex:: name () const

Returns the name of the index.

另請參閱 setName ().

void QSqlIndex:: setCursorName (const QString & cursorName )

Sets the name of the cursor that the index is associated with to cursorName .

另請參閱 cursorName ().

void QSqlIndex:: setDescending ( int i , bool desc )

desc is true, field i is sorted in descending order. Otherwise, field i is sorted in ascending order (the default). If the field does not exist, nothing happens.

另請參閱 isDescending ().

void QSqlIndex:: setName (const QString & name )

Sets the name of the index to name .

另請參閱 name ().

QSqlIndex &QSqlIndex:: operator= (const QSqlIndex & other )

Sets the index equal to other .