QSqlRelation Class

The QSqlRelation class stores information about an SQL foreign key. More...

Header: #include <QSqlRelation>
qmake: QT += sql

Public Functions

QSqlRelation()
QSqlRelation(const QString &tableName, const QString &indexColumn, const QString &displayColumn)
QString displayColumn() const
QString indexColumn() const
bool isValid() const
void swap(QSqlRelation &other)
QString tableName() const

Detailed Description

The QSqlRelation class stores information about an SQL foreign key.

QSqlRelation is a helper class for QSqlRelationalTableModel. See QSqlRelationalTableModel::setRelation() and QSqlRelationalTableModel::relation() for details.

See also QSqlRelationalTableModel, QSqlRelationalDelegate, and Relational Table Model Example.

Member Function Documentation

QSqlRelation::QSqlRelation()

Constructs an invalid QSqlRelation object.

For such an object, the tableName(), indexColumn(), and displayColumn() functions return an empty string.

See also isValid().

QSqlRelation::QSqlRelation(const QString &tableName, const QString &indexColumn, const QString &displayColumn)

Constructs a QSqlRelation object, where tableName is the SQL table name to which a foreign key refers, indexColumn is the foreign key, and displayColumn is the field that should be presented to the user.

See also tableName(), indexColumn(), and displayColumn().

QString QSqlRelation::displayColumn() const

Returns the column from table tableName() that should be presented to the user instead of a foreign key.

QString QSqlRelation::indexColumn() const

Returns the index column from table tableName() to which a foreign key refers.

bool QSqlRelation::isValid() const

Returns true if the QSqlRelation object is valid; otherwise returns false.

void QSqlRelation::swap(QSqlRelation &other)

Swaps this with other.

QString QSqlRelation::tableName() const

Returns the name of the table to which a foreign key refers.

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