QSql Namespace
The QSql namespace contains miscellaneous identifiers used throughout the Qt SQL module. More...
Header: | #include <QSql> |
qmake: | QT += sql |
Types
enum | Location { BeforeFirstRow, AfterLastRow } |
enum | NumericalPrecisionPolicy { LowPrecisionInt32, LowPrecisionInt64, LowPrecisionDouble, HighPrecision } |
flags | ParamType |
enum | ParamTypeFlag { In, Out, InOut, Binary } |
enum | TableType { Tables, SystemTables, Views, AllTables } |
Detailed Description
The QSql namespace contains miscellaneous identifiers used throughout the Qt SQL module.
See also Qt SQL.
Type Documentation
enum QSql::Location
This enum type describes special SQL navigation locations:
Constant | Value | Description |
---|---|---|
QSql::BeforeFirstRow |
-1 |
Before the first record. |
QSql::AfterLastRow |
-2 |
After the last record. |
See also QSqlQuery::at().
enum QSql::NumericalPrecisionPolicy
Numerical values in a database can have precisions greater than their corresponding C++ types. This enum lists the policies for representing such values in the application.
Constant | Value | Description |
---|---|---|
QSql::LowPrecisionInt32 |
0x01 |
Force 32bit integer values. In case of floating point numbers, the fractional part is silently discarded. |
QSql::LowPrecisionInt64 |
0x02 |
Force 64bit integer values. In case of floating point numbers, the fractional part is silently discarded. |
QSql::LowPrecisionDouble |
0x04 |
Force double values. This is the default policy. |
QSql::HighPrecision |
0 |
Strings will be used to preserve precision. |
Note: The actual behaviour if an overflow occurs is driver specific. The Oracle database just returns an error in this case.
enum QSql::ParamTypeFlagflags QSql::ParamType
This enum is used to specify the type of a bind parameter.
Constant | Value | Description |
---|---|---|
QSql::In |
0x00000001 |
The bind parameter is used to put data into the database. |
QSql::Out |
0x00000002 |
The bind parameter is used to receive data from the database. |
QSql::InOut |
In | Out |
The bind parameter is used to put data into the database; it will be overwritten with output data on executing a query. |
QSql::Binary |
0x00000004 |
This must be OR'd with one of the other flags if you want to indicate that the data being transferred is raw binary data. |
The ParamType type is a typedef for QFlags<ParamTypeFlag>. It stores an OR combination of ParamTypeFlag values.
enum QSql::TableType
This enum type describes types of SQL tables.
Constant | Value | Description |
---|---|---|
QSql::Tables |
0x01 |
All the tables visible to the user. |
QSql::SystemTables |
0x02 |
Internal tables used by the database. |
QSql::Views |
0x04 |
All the views visible to the user. |
QSql::AllTables |
0xff |
All of the above. |
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Licensed under the GNU Free Documentation License, Version 1.3.
https://doc.qt.io/qt-5.12/qsql.html