QSqlQuery wrapper with handy data fetch methods. More...

#include <EasyQtSql_QueryResult.h>

Public Member Functions
QSqlQuery &	unwrappedQuery ()
	Returns reference on wrapped QSqlQuery. More...

bool	next ()
	Retrieves the next record in the result, if available, and positions the query on the retrieved record. More...

bool	previous ()
	Retrieves the previous record in the result, if available, and positions the query on the retrieved record. More...

bool	nextResult ()
	Discards the current result set and navigates to the next if available (if database is capable of returning multiple result sets) More...

bool	first ()
	Retrieves the first record in the result, if available, and positions the query on the retrieved record. More...

bool	last ()
	Retrieves the last record in the result, if available, and positions the query on the retrieved record. More...

bool	seek (int index, bool relative=false)
	Retrieves the record at position index, if available, and positions the query on the retrieved record. More...

int	at () const
	Returns the current internal position of the query. The first record is at position zero. More...

bool	isActive () const
	Returns true if the query is active. An active QSqlQuery is one that has been exec()'d successfully but not yet finished with. More...

bool	isValid () const
	Returns true if the query is currently positioned on a valid record; otherwise returns false. More...

bool	isForwardOnly () const
	Returns true if you can only scroll forward through a result set; otherwise returns false. More...

int	size () const
	Returns the size of the result (number of rows returned), or -1 if the size cannot be determined or if the database does not support reporting information about query sizes. More...

int	numRowsAffected () const
	Returns the number of rows affected by the result's SQL statement, or -1 if it cannot be determined. More...

QSqlError	lastError () const
	Returns error information about the last error (if any) that occurred with this query. More...

QString	lastQuery () const
	Returns the text of the current query being used, or an empty string if there is no current query text. More...

QString	executedQuery () const
	Returns the last query that was successfully executed. More...

QVariant	value (int column) const
	Returns the value of field index in the current record. More...

QVariant	value (const QString &colName) const
	Returns the value of the field called name in the current record. If field name does not exist an invalid variant is returned. More...

QVariant	boundValue (int column) const
	Returns the value for the placeholder at position column. More...

QVariant	boundValue (const QString &aliasName) const
	Returns the value for the placeholder with aliasName. More...

QVariantList	boundValues () const
	Returns list of the bound values (with positional binding) More...

QVariantMap	toMap () const
	Returns QVariantMap filled with values fetched from current result row. Key is QString (result column name) and value is QVariant value. More...

QVariantList	toList () const
	Returns QVariantList filled with values fetched from current result row. More...

QStringList	toStringList () const
	Returns QStringList filled with values fetched from current result row. SQL values converted to QString with QVariant::toString() method. More...

QVector< QVariant >	toVector () const
	Returns QVector<QVariant> filled with values fetched from current result row. SQL values not converted: QSqlQuery::value() return value used. More...

template<typename T >
QVector< T >	toVector (bool skipNullValues=false) const
	Returns QVector<T> filled with values fetched from current result row. SQL values converted with QVariant::value<T>(). QVector::canConvert<T>() method used for convertability check. Non-convertable values skipped. More...

QVector< int >	parseToIntVector (int base=10, bool skipNullValues=false) const
	Returns vector of (optionally parsed) integer values from currently active result row. More...

template<typename T >
T	scalar () const
	Returns scalar value converted to type T (the value of the first column of the current row) More...

QVariant	scalar () const
	Returns scalar value (the value of the first column of the current row) More...

void	fetchVars (int &value) const
	Assigns a variable the value from the current record. More...

void	fetchVars (double &value) const
	Assigns a variable the value from the current record. More...

void	fetchVars (QString &value) const
	Assigns a variable the value from the current record. More...

void	fetchVars (bool &value) const
	Assigns a variable the value from the current record. More...

void	fetchVars (QDate &value) const
	Assigns a variable the value from the current record. More...

void	fetchVars (QDateTime &value) const
	Assigns a variable the value from the current record. More...

void	fetchVars (QTime &value) const
	Assigns a variable the value from the current record. More...

void	fetchVars (QByteArray &value) const
	Assigns a variable the value from the current record. More...

void	fetchVars (QVariant &value) const
	Assigns a variable the value from the current record. More...

template<typename... Rest>
void	fetchVars (int &value, Rest &... rest) const

template<typename... Rest>
void	fetchVars (double &value, Rest &... rest) const

template<typename... Rest>
void	fetchVars (QString &value, Rest &... rest) const

template<typename... Rest>
void	fetchVars (bool &value, Rest &... rest) const

template<typename... Rest>
void	fetchVars (QDate &value, Rest &... rest) const

template<typename... Rest>
void	fetchVars (QDateTime &value, Rest &... rest) const

template<typename... Rest>
void	fetchVars (QTime &value, Rest &... rest) const

template<typename... Rest>
void	fetchVars (QByteArray &value, Rest &... rest) const

template<typename... Rest>
void	fetchVars (QVariant &value, Rest &... rest) const

void	fetchObject (QObject &object) const
	Fills Q_OBJECT object properties with data fetched from current result row. More...

template<typename T >
void	fetchGadget (T &gadget) const
	Fills Q_GADGET object properties with data fetched from current result row. More...

void	fetchMap (QVariantMap &map) const
	Fills QVariantMap with values fetched from current result row. Key is QString (result column name) and value is QVariant value. More...

void	fetchList (QVariantList &list) const
	Fills QVariantList with values fetched from current result row. SQL values not converted: QSqlQuery::value() return value used. More...

void	fetchVector (QVector< QVariant > &vector) const
	Fills QVector<QVariant> with values fetched from current result row. SQL values not converted: QSqlQuery::value() return value used. More...

void	fetchStringList (QStringList &list) const
	Fills QStringList with values fetched from current result row. SQL values converted to QString with QVariant::toString() method. More...

Friends
class	Database

class	Transaction

class	PreparedQuery

Detailed Description

QSqlQuery wrapper with handy data fetch methods.

Member Function Documentation

◆ at()

int QueryResult::at ( ) const

inline

Returns the current internal position of the query. The first record is at position zero.

Returns: If the position is invalid, the function returns QSql::BeforeFirstRow or QSql::AfterLastRow, which are special negative values.

Wrapper over QSqlQuery::at()

◆ boundValue() [1/2]

QVariant QueryResult::boundValue ( int column ) const

inline

Returns the value for the placeholder at position column.

Wrapper over QSqlQuery::boundValue()

◆ boundValue() [2/2]

QVariant QueryResult::boundValue ( const QString & aliasName ) const

inline

Returns the value for the placeholder with aliasName.

Use subclasses of ParamDirectionWrapper class (In, Out, InOut) for aliased/directional parameter binding during PreparedQuery::exec execution

Use Out and InOut wrappers if you need to read Stored Procedures return values (output parameters).

See also: In, Out, InOut, PreparedQuery::exec

◆ boundValues()

QVariantList QueryResult::boundValues ( ) const

inline

Returns list of the bound values (with positional binding)

Wrapper over QSqlQuery::boundValues()

◆ executedQuery()

QString QueryResult::executedQuery ( ) const

inline

Returns the last query that was successfully executed.

Wrapper over QSqlQuery::executedQuery()

◆ fetchGadget()

template<typename T >

void QueryResult::fetchGadget ( T & gadget ) const

inline

Fills Q_GADGET object properties with data fetched from current result row.

Qt Meta-Object System used. Only writable properties can be filled.

C++ struct fields will be mapped on SQL result table by Q_PROPERTY member names. For example, if Q_GADGET struct contains Q_PROPERTY named "e" but SELECT query defines no "e" column, object property "e" not affected by the method.

struct Row
{
   int a;
   int b;
   int c;
   QString d;
   int e;
private:
   Q_GADGET
   //property "a" will be filled with "a" column of the Select SQL query result
   Q_PROPERTY(int a MEMBER a)
   Q_PROPERTY(int b MEMBER b)
   Q_PROPERTY(int c MEMBER c)
   Q_PROPERTY(QString d MEMBER d)
   //property e will be ignored in the example because there is no e field in the Select SQL query result
   Q_PROPERTY(int e MEMBER e)
};
void test()
{
   Transaction t;
   QueryResult res = t.execQuery("SELECT a, b, c, d FROM table");
   while (res.next())
   {
      //Row instance (Q_GADGET structure)
      Row testRow;
      //fetch testRow from current result row, properties a, b, c, d will be filled here:
      res.fetchGadget(testRow);
   }
}

Parameters

gadget Q_GADGET reference

◆ fetchList()

void QueryResult::fetchList ( QVariantList & list ) const

inline

Fills QVariantList with values fetched from current result row. SQL values not converted: QSqlQuery::value() return value used.

Parameters

[out] list QVariantList

See also: QueryResult::toList

◆ fetchMap()

void QueryResult::fetchMap ( QVariantMap & map ) const

inline

Fills QVariantMap with values fetched from current result row. Key is QString (result column name) and value is QVariant value.

Parameters

[out] map QVariantMap

See also: QueryResult::toMap

◆ fetchObject()

void QueryResult::fetchObject ( QObject & object ) const

inline

Fills Q_OBJECT object properties with data fetched from current result row.

Qt Meta-Object System used. Only writable properties can be filled.

C++ class fields (properties) will be mapped on SQL result table by Q_PROPERTY member names. For example, if Q_OBJECT class contains Q_PROPERTY named "e" but SELECT query defines no "e" column, object property "e" not affected by the method.

class TestObject : public QObject
{
   Q_OBJECT
   //property "a" will be filled with "a" column of the Select SQL query result
   Q_PROPERTY(int a MEMBER a)
   Q_PROPERTY(int b MEMBER b)
   Q_PROPERTY(int c MEMBER c)
   Q_PROPERTY(QString d MEMBER d)
   //property e will be ignored in the example because there is no e field in the Select SQL query result
   Q_PROPERTY(int e MEMBER e)
private:
   int a;
   int b;
   int c;
   QString d;
   int e;
};
void test()
{
   Transaction t;
   QueryResult res = t.execQuery("SELECT a, b, c, d FROM table");
   while (res.next())
   {
      //TestObject instance (Q_OBJECT class)
      TestObject testRow;
      res.fetchObject(testRow);
   }
}

Parameters

object Q_OBJECT object reference

◆ fetchStringList()

void QueryResult::fetchStringList ( QStringList & list ) const

inline

Fills QStringList with values fetched from current result row. SQL values converted to QString with QVariant::toString() method.

Parameters

[out] list QStringList

See also: QueryResult::toStringList

◆ fetchVars() [1/18]

void QueryResult::fetchVars ( int & value ) const

inline

Assigns a variable the value from the current record.

The method has a variable number of parameters, which allows filling the list of variables with values from the current record in single call.

Overloaded EasyQtSql::fetchVars methods performs the corresponding type conversion with QVariant::to*() methods.

Supported parameter types: int, double, bool, QString, QDate, QDateTime, QTime, QByteArray, QVariant.

Variables of different types can be mixed.

Transaction t;
QueryResult res = t.execQuery("SELECT a, b, c, d FROM table");
while (res.next())
{
   int a;
   bool b;
   QString c;
   QDateTime d;
   res.fetchVars(a, b, c, d);
}

See also: QueryResult::fetchVars(int&) const , QueryResult::fetchVars(double&) const , QueryResult::fetchVars(QString&) const , QueryResult::fetchVars(bool&) const , QueryResult::fetchVars(QDate&) const , QueryResult::fetchVars(QDateTime&) const , QueryResult::fetchVars(QTime&) const , QueryResult::fetchVars(QByteArray&) const , QueryResult::fetchVars(QVariant&) const

◆ fetchVars() [2/18]

void QueryResult::fetchVars ( double & value ) const

inline

Assigns a variable the value from the current record.

See also: QueryResult::fetchVars(int&) const

◆ fetchVars() [3/18]

void QueryResult::fetchVars ( QString & value ) const

inline

Assigns a variable the value from the current record.

See also: QueryResult::fetchVars(int&) const

◆ fetchVars() [4/18]

void QueryResult::fetchVars ( bool & value ) const

inline

Assigns a variable the value from the current record.

See also: QueryResult::fetchVars(int&) const

◆ fetchVars() [5/18]

void QueryResult::fetchVars ( QDate & value ) const

inline

Assigns a variable the value from the current record.

See also: QueryResult::fetchVars(int&) const

◆ fetchVars() [6/18]

void QueryResult::fetchVars ( QDateTime & value ) const

inline

Assigns a variable the value from the current record.

See also: QueryResult::fetchVars(int&) const

◆ fetchVars() [7/18]

void QueryResult::fetchVars ( QTime & value ) const

inline

Assigns a variable the value from the current record.

See also: QueryResult::fetchVars(int&) const

◆ fetchVars() [8/18]

void QueryResult::fetchVars ( QByteArray & value ) const

inline

Assigns a variable the value from the current record.

See also: QueryResult::fetchVars(int&) const

◆ fetchVars() [9/18]

void QueryResult::fetchVars ( QVariant & value ) const

inline

Assigns a variable the value from the current record.

See also: QueryResult::fetchVars(int&) const

◆ fetchVars() [10/18]

template<typename... Rest>

void QueryResult::fetchVars	(	int &	value,
		Rest &...	rest
	)		const

inline

◆ fetchVars() [11/18]

template<typename... Rest>

void QueryResult::fetchVars	(	double &	value,
		Rest &...	rest
	)		const

inline

◆ fetchVars() [12/18]

template<typename... Rest>

void QueryResult::fetchVars	(	QString &	value,
		Rest &...	rest
	)		const

inline

◆ fetchVars() [13/18]

template<typename... Rest>

void QueryResult::fetchVars	(	bool &	value,
		Rest &...	rest
	)		const

inline

◆ fetchVars() [14/18]

template<typename... Rest>

void QueryResult::fetchVars	(	QDate &	value,
		Rest &...	rest
	)		const

inline

◆ fetchVars() [15/18]

template<typename... Rest>

void QueryResult::fetchVars	(	QDateTime &	value,
		Rest &...	rest
	)		const

inline

◆ fetchVars() [16/18]

template<typename... Rest>

void QueryResult::fetchVars	(	QTime &	value,
		Rest &...	rest
	)		const

inline

◆ fetchVars() [17/18]

template<typename... Rest>

void QueryResult::fetchVars	(	QByteArray &	value,
		Rest &...	rest
	)		const

inline

◆ fetchVars() [18/18]

template<typename... Rest>

void QueryResult::fetchVars	(	QVariant &	value,
		Rest &...	rest
	)		const

inline

◆ fetchVector()

void QueryResult::fetchVector ( QVector< QVariant > & vector ) const

inline

Fills QVector<QVariant> with values fetched from current result row. SQL values not converted: QSqlQuery::value() return value used.

Parameters

[out] vector QVector<QVariant>

See also: QueryResult::toVector

◆ first()

bool QueryResult::first ( )

inline

Retrieves the first record in the result, if available, and positions the query on the retrieved record.

Wrapper over QSqlQuery::first()

◆ isActive()

bool QueryResult::isActive ( ) const

inline

Returns true if the query is active. An active QSqlQuery is one that has been exec()'d successfully but not yet finished with.

Wrapper over QSqlQuery::isActive()

◆ isForwardOnly()

bool QueryResult::isForwardOnly ( ) const

inline

Returns true if you can only scroll forward through a result set; otherwise returns false.

Wrapper over QSqlQuery::isForwardOnly()

◆ isValid()

bool QueryResult::isValid ( ) const

inline

Returns true if the query is currently positioned on a valid record; otherwise returns false.

Wrapper over QSqlQuery::isValid()

◆ last()

bool QueryResult::last ( )

inline

Retrieves the last record in the result, if available, and positions the query on the retrieved record.

Wrapper over QSqlQuery::last()

◆ lastError()

QSqlError QueryResult::lastError ( ) const

inline

Returns error information about the last error (if any) that occurred with this query.

Wrapper over QSqlQuery::lastError()

◆ lastQuery()

QString QueryResult::lastQuery ( ) const

inline

Returns the text of the current query being used, or an empty string if there is no current query text.

Wrapper over QSqlQuery::lastQuery()

◆ next()

bool QueryResult::next ( )

inline

Retrieves the next record in the result, if available, and positions the query on the retrieved record.

Wrapper over QSqlQuery::next()

◆ nextResult()

bool QueryResult::nextResult ( )

inline

Discards the current result set and navigates to the next if available (if database is capable of returning multiple result sets)

Wrapper over QSqlQuery::nextResult()

◆ numRowsAffected()

int QueryResult::numRowsAffected ( ) const

inline

Returns the number of rows affected by the result's SQL statement, or -1 if it cannot be determined.

Wrapper over QSqlQuery::numRowsAffected()

◆ parseToIntVector()

QVector<int> QueryResult::parseToIntVector	(	int	base = `10`,
		bool	skipNullValues = `false`
	)		const

inline

Returns vector of (optionally parsed) integer values from currently active result row.

Parsing with specified base will be performed if type of selected database field is String (varchar/text). Not successfully parsed string values are ignored.

Parameters

base	Number base to parse int values from SQL string values.
skipNullValues	Skip SQL NULL values. Resulting int value is 0 if skipNullValues = false.

◆ previous()

bool QueryResult::previous ( )

inline

Retrieves the previous record in the result, if available, and positions the query on the retrieved record.

Wrapper over QSqlQuery::previous()

◆ scalar() [1/2]

template<typename T >

T QueryResult::scalar ( ) const

inline

Returns scalar value converted to type T (the value of the first column of the current row)

◆ scalar() [2/2]

QVariant QueryResult::scalar ( ) const

inline

Returns scalar value (the value of the first column of the current row)

◆ seek()

bool QueryResult::seek	(	int	index,
		bool	relative = `false`
	)

inline

Retrieves the record at position index, if available, and positions the query on the retrieved record.

Wrapper over QSqlQuery::seek()

◆ size()

int QueryResult::size ( ) const

inline

Returns the size of the result (number of rows returned), or -1 if the size cannot be determined or if the database does not support reporting information about query sizes.

Wrapper over QSqlQuery::size()

◆ toList()

QVariantList QueryResult::toList ( ) const

inline

Returns QVariantList filled with values fetched from current result row.

See also: QueryResult::fetchList

◆ toMap()

QVariantMap QueryResult::toMap ( ) const

inline

Returns QVariantMap filled with values fetched from current result row. Key is QString (result column name) and value is QVariant value.

See also: QueryResult::fetchMap

◆ toStringList()

QStringList QueryResult::toStringList ( ) const

inline

Returns QStringList filled with values fetched from current result row. SQL values converted to QString with QVariant::toString() method.

See also: QueryResult::fetchStringList()

◆ toVector() [1/2]

QVector<QVariant> QueryResult::toVector ( ) const

inline

Returns QVector<QVariant> filled with values fetched from current result row. SQL values not converted: QSqlQuery::value() return value used.

See also: QueryResult::fetchVector

◆ toVector() [2/2]

template<typename T >

QVector<T> QueryResult::toVector ( bool skipNullValues = false ) const

inline

Returns QVector<T> filled with values fetched from current result row. SQL values converted with QVariant::value<T>(). QVector::canConvert<T>() method used for convertability check. Non-convertable values skipped.

Parameters

skipNullValues Skip SQL NULL values. Resulting value is default value if skipNullValues = false.

See also: QueryResult::toVector

◆ unwrappedQuery()

QSqlQuery& QueryResult::unwrappedQuery ( )

inline

Returns reference on wrapped QSqlQuery.

◆ value() [1/2]

QVariant QueryResult::value ( int column ) const

inline

Returns the value of field index in the current record.

Wrapper over QSqlQuery::value()

◆ value() [2/2]

QVariant QueryResult::value ( const QString & colName ) const

inline

Returns the value of the field called name in the current record. If field name does not exist an invalid variant is returned.

Wrapper over QSqlQuery::value()

Friends And Related Function Documentation

◆ Database

friend class Database

friend

◆ PreparedQuery

friend class PreparedQuery

friend

◆ Transaction

friend class Transaction

friend

The documentation for this class was generated from the following file:

EasyQtSql/EasyQtSql_QueryResult.h

Public Member Functions

Friends

Detailed Description

Member Function Documentation

◆ at()

◆ boundValue() [1/2]

◆ boundValue() [2/2]

◆ boundValues()

◆ executedQuery()

◆ fetchGadget()

◆ fetchList()

◆ fetchMap()

◆ fetchObject()

◆ fetchStringList()

◆ fetchVars() [1/18]

◆ fetchVars() [2/18]

◆ fetchVars() [3/18]

◆ fetchVars() [4/18]

◆ fetchVars() [5/18]

◆ fetchVars() [6/18]

◆ fetchVars() [7/18]

◆ fetchVars() [8/18]

◆ fetchVars() [9/18]

◆ fetchVars() [10/18]

◆ fetchVars() [11/18]

◆ fetchVars() [12/18]

◆ fetchVars() [13/18]

◆ fetchVars() [14/18]

◆ fetchVars() [15/18]

◆ fetchVars() [16/18]

◆ fetchVars() [17/18]

◆ fetchVars() [18/18]

◆ fetchVector()

◆ first()

◆ isActive()

◆ isForwardOnly()

◆ isValid()

◆ last()

◆ lastError()

◆ lastQuery()

◆ next()

◆ nextResult()

◆ numRowsAffected()

◆ parseToIntVector()

◆ previous()

◆ scalar() [1/2]

◆ scalar() [2/2]

◆ seek()

◆ size()

◆ toList()

◆ toMap()

◆ toStringList()

◆ toVector() [1/2]

◆ toVector() [2/2]

◆ unwrappedQuery()

◆ value() [1/2]

◆ value() [2/2]

Friends And Related Function Documentation

◆ Database

◆ PreparedQuery

◆ Transaction