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 |
| 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.
QString QSqlRelation::tableName() const
Returns the name of the table to which a foreign key refers.