QSqlDatabase wrapper. More...

#include <EasyQtSql_Transaction.h>

Inheritance diagram for Database:

Public Member Functions
	Database (const QSqlDatabase &db=QSqlDatabase())

	Database (Database &&other)

Database &	operator= (Database &&other)

QSqlError	lastError () const
	Returns information about the last error that occurred on the underlying database. More...

NonQueryResult	execNonQuery (const QString &sql) const
	Executes non-query SQL statement (DELETE, INSERT, UPDATE, CREATE, ALTER, etc.) More...

QueryResult	execQuery (const QString &sql) const
	Executes SELECT query. More...

InsertQuery	insertInto (const QString &table) const
	Creates INSERT query wrapper. More...

DeleteQuery	deleteFrom (const QString &table) const
	Creates DELETE query wrapper. More...

UpdateQuery	update (const QString &table) const
	Creates UPDATE query wrapper. More...

PreparedQuery	prepare (const QString &sql, bool forwardOnly=true) const
	Prepares SQL statement. More...

QSqlDatabase &	qSqlDatabase ()
	Returns a reference to the wrapped QSqlDatabase object. More...

template<typename Func >
int	each (const QString &query, Func &&f) const
	Executes query and applies function f to each result row. More...

template<typename Func >
int	first (const QString &query, Func &&f) const
	Executes query and applies function f to the first result row. More...

template<typename Func >
int	range (const QString &query, int start, int count, Func &&f) const
	Executes query and applies function f to count result rows starting from index start. More...

template<typename Func >
int	top (const QString &query, int topCount, Func &&f) const
	Executes query and applies function f to topCount result rows. More...

template<typename T >
T	scalar (const QString &query) const
	Executes query and returns scalar value converted to T. More...

QVariant	scalar (const QString &query) const
	Executes query and returns scalar value. More...

Protected Attributes
QSqlDatabase	m_db

Detailed Description

QSqlDatabase wrapper.

void test()
{
   QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
   db.setDatabaseName(":memory:");
   try
   {
      Database sdb(db);
      sdb.execNonQuery("CREATE TABLE table (a int, b int, c int, d text)");
   }
   catch (const DBException &e)
   {
      //you can handle all the errors at one point
      qDebug() << e.lastError << e.lastQuery;
   }
}

Constructor & Destructor Documentation

◆ Database() [1/2]

Database::Database ( const QSqlDatabase & db = QSqlDatabase() )

inlineexplicit

Parameters

db	QSqlDatabase to use

Creates an Database object, tries to open db connection if not opened.

Exceptions

DBException

◆ Database() [2/2]

Database::Database ( Database && other )

inline

Member Function Documentation

◆ deleteFrom()

DeleteQuery Database::deleteFrom ( const QString & table ) const

inline

Creates DELETE query wrapper.

Parameters

table Table to delete from

◆ each()

template<typename Func >

int Database::each	(	const QString &	query,
		Func &&	f
	)		const

inline

Executes query and applies function f to each result row.

Parameters

query	SQL query string (SELECT statement)
f	Function (lambda) to apply to

Returns: num rows handled with function f

Database db;
db.each("SELECT * FROM table", [](const QueryResult &res)
{
   qDebug() << res.toMap();
});

◆ execNonQuery()

NonQueryResult Database::execNonQuery ( const QString & sql ) const

inline

Executes non-query SQL statement (DELETE, INSERT, UPDATE, CREATE, ALTER, etc.)

Parameters

query SQL statement string

Exceptions

DBException

◆ execQuery()

QueryResult Database::execQuery ( const QString & sql ) const

inline

Executes SELECT query.

Parameters

query SQL statement string

Exceptions

DBException

◆ first()

template<typename Func >

int Database::first	(	const QString &	query,
		Func &&	f
	)		const

inline

Executes query and applies function f to the first result row.

Parameters

query	SQL query string (SELECT statement)
f	Function (lambda) to apply to

Returns: num rows handled with function f

Database db;
db.first("SELECT * FROM table", [](const QueryResult &res)
{
   qDebug() << res.toMap();
});

◆ insertInto()

InsertQuery Database::insertInto ( const QString & table ) const

inline

Creates INSERT query wrapper.

Parameters

table Table to insert into with list of columns

◆ lastError()

QSqlError Database::lastError ( ) const

inline

Returns information about the last error that occurred on the underlying database.

◆ operator=()

Database& Database::operator= ( Database && other )

inline

◆ prepare()

PreparedQuery Database::prepare	(	const QString &	sql,
		bool	forwardOnly = `true`
	)		const

inline

Prepares SQL statement.

Parameters

sql	SQL statement string
forwardOnly	Configure underlying QSqlQuery as forwardOnly

◆ qSqlDatabase()

QSqlDatabase& Database::qSqlDatabase ( )

inline

Returns a reference to the wrapped QSqlDatabase object.

◆ range()

template<typename Func >

int Database::range	(	const QString &	query,
		int	start,
		int	count,
		Func &&	f
	)		const

inline

Executes query and applies function f to count result rows starting from index start.

Parameters

query	SQL query string (SELECT statement)
start	Start index
count	Row count to handle
f	Function (lambda) to apply to

Returns: num rows handled with function f

Database db;
db.range("SELECT * FROM table", 3, 10, [](const QueryResult &res)
{
   qDebug() << res.toMap();
});

◆ scalar() [1/2]

template<typename T >

T Database::scalar ( const QString & query ) const

inline

Executes query and returns scalar value converted to T.

Parameters

query SQL query string (SELECT statement)

See also: QueryResult::scalar

◆ scalar() [2/2]

QVariant Database::scalar ( const QString & query ) const

inline

Executes query and returns scalar value.

Parameters

query SQL query string (SELECT statement)

See also: QueryResult::scalar

◆ top()

template<typename Func >

int Database::top	(	const QString &	query,
		int	topCount,
		Func &&	f
	)		const

inline

Executes query and applies function f to topCount result rows.

Parameters

query	SQL query string (SELECT statement)
topCount	Row count to handle
f	Function (lambda) to apply to

Returns: num rows handled with function f

Database db;
db.top("SELECT * FROM table", 10, [](const QueryResult &res)
{
   qDebug() << res.toMap();
});

◆ update()

UpdateQuery Database::update ( const QString & table ) const

inline

Creates UPDATE query wrapper.

Parameters

table Table to update

Member Data Documentation

◆ m_db

QSqlDatabase Database::m_db

protected

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

EasyQtSql/EasyQtSql_Transaction.h

Public Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ Database() [1/2]

◆ Database() [2/2]

Member Function Documentation

◆ deleteFrom()

◆ each()

◆ execNonQuery()

◆ execQuery()

◆ first()

◆ insertInto()

◆ lastError()

◆ operator=()

◆ prepare()

◆ qSqlDatabase()

◆ range()

◆ scalar() [1/2]

◆ scalar() [2/2]

◆ top()

◆ update()

Member Data Documentation

◆ m_db