QSqlRecord Class
The QSqlRecord class encapsulates a database record. More...
| Header: | #include <QSqlRecord> |
| qmake: | QT += sql |
| Inherited By: |
Public Functions
| QSqlRecord() | |
| QSqlRecord(const QSqlRecord &other) | |
| ~QSqlRecord() | |
| void | append(const QSqlField &field) |
| void | clear() |
| void | clearValues() |
| bool | contains(const QString &name) const |
| int | count() const |
| QSqlField | field(int index) const |
| QSqlField | field(const QString &name) const |
| QString | fieldName(int index) const |
| int | indexOf(const QString &name) const |
| void | insert(int pos, const QSqlField &field) |
| bool | isEmpty() const |
| bool | isGenerated(const QString &name) const |
| bool | isGenerated(int index) const |
| bool | isNull(const QString &name) const |
| bool | isNull(int index) const |
| QSqlRecord | keyValues(const QSqlRecord &keyFields) const |
| void | remove(int pos) |
| void | replace(int pos, const QSqlField &field) |
| void | setGenerated(const QString &name, bool generated) |
| void | setGenerated(int index, bool generated) |
| void | setNull(int index) |
| void | setNull(const QString &name) |
| void | setValue(int index, const QVariant &val) |
| void | setValue(const QString &name, const QVariant &val) |
| QVariant | value(int index) const |
| QVariant | value(const QString &name) const |
| bool | operator!=(const QSqlRecord &other) const |
| QSqlRecord & | operator=(const QSqlRecord &other) |
| bool | operator==(const QSqlRecord &other) const |
Detailed Description
The QSqlRecord class encapsulates a database record.
The QSqlRecord class encapsulates the functionality and characteristics of a database record (usually a row in a table or view within the database). QSqlRecord supports adding and removing fields as well as setting and retrieving field values.
The values of a record's fields can be set by name or position with setValue(); if you want to set a field to null use setNull(). To find the position of a field by name use indexOf(), and to find the name of a field at a particular position use fieldName(). Use field() to retrieve a QSqlField object for a given field. Use contains() to see if the record contains a particular field name.
When queries are generated to be executed on the database only those fields for which isGenerated() is true are included in the generated SQL.
A record can have fields added with append() or insert(), replaced with replace(), and removed with remove(). All the fields can be removed with clear(). The number of fields is given by count(); all their values can be cleared (to null) using clearValues().
See also QSqlField and QSqlQuery::record().
Member Function Documentation
QSqlRecord::QSqlRecord()
Constructs an empty record.
See also isEmpty(), append(), and insert().
QSqlRecord::QSqlRecord(const QSqlRecord &other)
Constructs a copy of other.
QSqlRecord is implicitly shared. This means you can make copies of a record in constant time.
QSqlRecord::~QSqlRecord()
Destroys the object and frees any allocated resources.
void QSqlRecord::append(const QSqlField &field)
Append a copy of field field to the end of the record.
See also insert(), replace(), and remove().
void QSqlRecord::clear()
Removes all the record's fields.
See also clearValues() and isEmpty().
void QSqlRecord::clearValues()
Clears the value of all fields in the record and sets each field to null.
See also setValue().
bool QSqlRecord::contains(const QString &name) const
Returns true if there is a field in the record called name; otherwise returns false.
int QSqlRecord::count() const
Returns the number of fields in the record.
See also isEmpty().
QSqlField QSqlRecord::field(int index) const
Returns the field at position index. If the index is out of range, function returns a default-constructed value.
QSqlField QSqlRecord::field(const QString &name) const
This is an overloaded function.
Returns the field called name.
QString QSqlRecord::fieldName(int index) const
Returns the name of the field at position index. If the field does not exist, an empty string is returned.
See also indexOf().
int QSqlRecord::indexOf(const QString &name) const
Returns the position of the field called name within the record, or -1 if it cannot be found. Field names are not case-sensitive. If more than one field matches, the first one is returned.
See also fieldName().
void QSqlRecord::insert(int pos, const QSqlField &field)
Inserts the field field at position pos in the record.
See also append(), replace(), and remove().
bool QSqlRecord::isEmpty() const
Returns true if there are no fields in the record; otherwise returns false.
See also append(), insert(), and clear().
bool QSqlRecord::isGenerated(const QString &name) const
Returns true if the record has a field called name and this field is to be generated (the default); otherwise returns false.
See also setGenerated().
bool QSqlRecord::isGenerated(int index) const
This is an overloaded function.
Returns true if the record has a field at position index and this field is to be generated (the default); otherwise returns false.
See also setGenerated().
bool QSqlRecord::isNull(const QString &name) const
Returns true if the field called name is null or if there is no field called name; otherwise returns false.
See also setNull().
bool QSqlRecord::isNull(int index) const
This is an overloaded function.
Returns true if the field index is null or if there is no field at position index; otherwise returns false.
QSqlRecord QSqlRecord::keyValues(const QSqlRecord &keyFields) const
Returns a record containing the fields represented in keyFields set to values that match by field name.
This function was introduced in Qt 5.1.
void QSqlRecord::remove(int pos)
Removes the field at position pos. If pos is out of range, nothing happens.
See also append(), insert(), and replace().
void QSqlRecord::replace(int pos, const QSqlField &field)
Replaces the field at position pos with the given field. If pos is out of range, nothing happens.
See also append(), insert(), and remove().
void QSqlRecord::setGenerated(const QString &name, bool generated)
Sets the generated flag for the field called name to generated. If the field does not exist, nothing happens. Only fields that have generated set to true are included in the SQL that is generated by QSqlQueryModel for example.
See also isGenerated().
void QSqlRecord::setGenerated(int index, bool generated)
This is an overloaded function.
Sets the generated flag for the field index to generated.
See also isGenerated().
void QSqlRecord::setNull(int index)
Sets the value of field index to null. If the field does not exist, nothing happens.
See also isNull() and setValue().
void QSqlRecord::setNull(const QString &name)
This is an overloaded function.
Sets the value of the field called name to null. If the field does not exist, nothing happens.
void QSqlRecord::setValue(int index, const QVariant &val)
Sets the value of the field at position index to val. If the field does not exist, nothing happens.
See also value() and setNull().
void QSqlRecord::setValue(const QString &name, const QVariant &val)
This is an overloaded function.
Sets the value of the field called name to val. If the field does not exist, nothing happens.
QVariant QSqlRecord::value(int index) const
Returns the value of the field located at position index in the record. If index is out of bounds, an invalid QVariant is returned.
See also setValue(), fieldName(), and isNull().
QVariant QSqlRecord::value(const QString &name) const
This is an overloaded function.
Returns the value of the field called name in the record. If field name does not exist an invalid variant is returned.
See also indexOf().
bool QSqlRecord::operator!=(const QSqlRecord &other) const
Returns true if this object is not identical to other; otherwise returns false.
See also operator==().
QSqlRecord &QSqlRecord::operator=(const QSqlRecord &other)
Sets the record equal to other.
QSqlRecord is implicitly shared. This means you can make copies of a record in constant time.
bool QSqlRecord::operator==(const QSqlRecord &other) const
Returns true if this object is identical to other (i.e., has the same fields in the same order); otherwise returns false.
See also operator!=().