QSqlField#

The QSqlField class manipulates the fields in SQL database tables and views. More…

Synopsis#

Functions#

def clear ()
def defaultValue ()
def isAutoValue ()
def isGenerated ()
def isNull ()
def isReadOnly ()
def isValid ()
def length ()
def metaType ()
def name ()
def __ne__ (other)
def __eq__ (other)
def precision ()
def requiredStatus ()
def setAutoValue (autoVal)
def setDefaultValue (value)
def setGenerated (gen)
def setLength (fieldLength)
def setMetaType (type)
def setName (name)
def setPrecision (precision)
def setReadOnly (readOnly)
def setRequired (required)
def setRequiredStatus (status)
def setSqlType (type)
def setTableName (tableName)
def setValue (value)
def swap (other)
def tableName ()
def typeID ()
def value ()

Note

This documentation may contain snippets that were automatically translated from C++ to Python. We always welcome contributions to the snippet translation. If you see an issue with the translation, you can also let us know by creating a ticket on https:/bugreports.qt.io/projects/PYSIDE

Detailed Description#

Warning

This section contains snippets that were automatically translated from C++ to Python and may contain errors.

QSqlField represents the characteristics of a single column in a database table or view, such as the data type and column name. A field also contains the value of the database column, which can be viewed or changed.

Field data values are stored as QVariants. Using an incompatible type is not permitted. For example:

field = QSqlField("age", QMetaType.fromType())
    field.setValue(QPixmap()) # WRONG

However, the field will attempt to cast certain data types to the field data type where possible:

field = QSqlField("age", QMetaType.fromType())
    field.setValue(QString("123")) # casts QString to int

QSqlField objects are rarely created explicitly in application code. They are usually accessed indirectly through QSqlRecord s that already contain a list of fields. For example:

query = QSqlQuery()            ...

record = query.record()
field = record.field("country")

A QSqlField object can provide some meta-data about the field, for example, its name() , variant type(), length() , precision() , defaultValue() , typeID(), and its requiredStatus() , isGenerated() and isReadOnly() . The field’s data can be checked to see if it isNull() , and its value() retrieved. When editing the data can be set with setValue() or set to NULL with clear() .

See also

QSqlRecord

class PySide6.QtSql.QSqlField(other)#

PySide6.QtSql.QSqlField([fieldName=””[, type=QMetaType()[, tableName=””]]])

Parameters:

other – PySide6.QtSql.QSqlField
type – PySide6.QtCore.QMetaType
fieldName – str
tableName – str

Constructs a copy of other.

This is an overloaded function.

Constructs an empty field called fieldName of type type in table.

See also

setRequiredStatus() setLength() setPrecision() setDefaultValue() setGenerated() setReadOnly()

PySide6.QtSql.QSqlField.RequiredStatus#

Specifies whether the field is required or optional.

Constant

Description

QSqlField.Required

The field must be specified when inserting records.

QSqlField.Optional

The fields doesn’t have to be specified when inserting records.

QSqlField.Unknown

The database driver couldn’t determine whether the field is required or optional.

See also

requiredStatus()

Constant	Description
QSqlField.Required	The field must be specified when inserting records.
QSqlField.Optional	The fields doesn’t have to be specified when inserting records.
QSqlField.Unknown	The database driver couldn’t determine whether the field is required or optional.

PySide6.QtSql.QSqlField.clear()#

Clears the value of the field and sets it to NULL. If the field is read-only, nothing happens.

See also

setValue() isReadOnly() requiredStatus()

PySide6.QtSql.QSqlField.defaultValue()#

Return type:: object

Returns the field’s default value (which may be NULL).

See also

setDefaultValue() metaType() requiredStatus() length() precision() isGenerated()

PySide6.QtSql.QSqlField.isAutoValue()#

Return type:: bool

Returns true if the value is auto-generated by the database, for example auto-increment primary key values.

Note

When using the ODBC driver, due to limitations in the ODBC API, the isAutoValue() field is only populated in a QSqlField resulting from a QSqlRecord obtained by executing a SELECT query. It is false in a QSqlField resulting from a QSqlRecord returned from record() or primaryIndex() .