Wt::Dbo::SqlStatement Class Reference

Abstract base class for a prepared SQL statement. More...

#include <SqlStatement.h>

Inheritance diagram for Wt::Dbo::SqlStatement:

Public Member Functions
virtual	~SqlStatement ()
	Destructor.
bool	use ()
	Uses the statement.
void	done ()
	Finish statement use.
virtual void	reset ()=0
	Resets the statement.
virtual void	bind (int column, const std::string &value)=0
	Binds a value to a column.
virtual void	bind (int column, short value)=0
	Binds a value to a column.
virtual void	bind (int column, int value)=0
	Binds a value to a column.
virtual void	bind (int column, long long value)=0
	Binds a value to a column.
virtual void	bind (int column, float value)=0
	Binds a value to a column.
virtual void	bind (int column, double value)=0
	Binds a value to a column.
virtual void	bind (int column, const std::chrono::system_clock::time_point &value, SqlDateTimeType type)=0
	Binds a value to a column.
virtual void	bind (int column, const std::chrono::duration< int, std::milli > &value)=0
	Binds a value to a column.
virtual void	bind (int column, const std::vector< unsigned char > &value)=0
	Binds a value to a column.
virtual void	bindNull (int column)=0
	Binds null to a column.
virtual void	execute ()=0
	Executes the statement.
virtual long long	insertedId ()=0
	Returns the id if the statement was an SQL insert.
virtual int	affectedRowCount ()=0
	Returns the affected number of rows.
virtual bool	nextRow ()=0
	Fetches the next result row.
virtual int	columnCount () const =0
	Returns the number of columns in the result.
virtual bool	getResult (int column, std::string *value, int size)=0
	Fetches a result value.
virtual bool	getResult (int column, short *value)=0
	Fetches a result value.
virtual bool	getResult (int column, int *value)=0
	Fetches a result value.
virtual bool	getResult (int column, long long *value)=0
	Fetches a result value.
virtual bool	getResult (int column, float *value)=0
	Fetches a result value.
virtual bool	getResult (int column, double *value)=0
	Fetches a result value.
virtual bool	getResult (int column, std::chrono::system_clock::time_point *value, SqlDateTimeType type)=0
	Fetches a result value.
virtual bool	getResult (int column, std::chrono::duration< int, std::milli > *value)=0
	Fetches a result value.
virtual bool	getResult (int column, std::vector< unsigned char > *value, int size)=0
	Fetches a result value.
virtual std::string	sql () const =0
	Returns the prepared SQL string.

Detailed Description

Abstract base class for a prepared SQL statement.

The statement may be used multiple times, but cannot be used concurrently. It also cannot be copied.

This class is part of Wt::Dbo's backend API, and should not be used directly. Its interface must be reimplemented for each backend corresponding to a supported database.

See also

SqlConnection

Member Function Documentation

affectedRowCount()

virtual int Wt::Dbo::SqlStatement::affectedRowCount ( )

pure virtual

Returns the affected number of rows.

This is only useful for an SQL update or delete statement.

Implemented in Wt::Dbo::backend::MySQLStatement.

columnCount()

virtual int Wt::Dbo::SqlStatement::columnCount ( ) const

pure virtual

Returns the number of columns in the result.

Note

The column count may only be available after the query was executed.

Implemented in Wt::Dbo::backend::MySQLStatement.

done()

void Wt::Dbo::SqlStatement::done

(

)

Finish statement use.

Marks the statement as no longer used and resets the statement.

See also

use()

getResult() [1/9]

virtual bool Wt::Dbo::SqlStatement::getResult ( int  column, double *  value  )

pure virtual

Fetches a result value.

Returns true when the value was not null.

Implemented in Wt::Dbo::backend::MySQLStatement.

getResult() [2/9]

virtual bool Wt::Dbo::SqlStatement::getResult ( int  column, float *  value  )

pure virtual

Fetches a result value.

Returns true when the value was not null.

Implemented in Wt::Dbo::backend::MySQLStatement.

getResult() [3/9]

virtual bool Wt::Dbo::SqlStatement::getResult ( int  column, int *  value  )

pure virtual

Fetches a result value.

Returns true when the value was not null.

Implemented in Wt::Dbo::backend::MySQLStatement.

getResult() [4/9]

virtual bool Wt::Dbo::SqlStatement::getResult ( int  column, long long *  value  )

pure virtual

Fetches a result value.

Returns true when the value was not null.

Implemented in Wt::Dbo::backend::MySQLStatement.

getResult() [5/9]

virtual bool Wt::Dbo::SqlStatement::getResult ( int  column, short *  value  )

pure virtual

Fetches a result value.

Returns true when the value was not null.

Implemented in Wt::Dbo::backend::MySQLStatement.

getResult() [6/9]

virtual bool Wt::Dbo::SqlStatement::getResult ( int  column, std::chrono::duration< int, std::milli > *  value  )

pure virtual

Fetches a result value.

Returns true when the value was not null.

Implemented in Wt::Dbo::backend::MySQLStatement.

getResult() [7/9]

virtual bool Wt::Dbo::SqlStatement::getResult ( int  column, std::chrono::system_clock::time_point *  value, SqlDateTimeType  type  )

pure virtual

Fetches a result value.

Returns true when the value was not null.

Implemented in Wt::Dbo::backend::MySQLStatement.

getResult() [8/9]

virtual bool Wt::Dbo::SqlStatement::getResult ( int  column, std::string *  value, int  size  )

pure virtual

Fetches a result value.

Returns true when the value was not null. The size is the expected size of sql string type and can be used to dimension buffers but the return string may be bigger.

getResult() [9/9]

virtual bool Wt::Dbo::SqlStatement::getResult ( int  column, std::vector< unsigned char > *  value, int  size  )

pure virtual

Fetches a result value.

Returns true when the value was not null.

nextRow()

virtual bool Wt::Dbo::SqlStatement::nextRow ( )

pure virtual

Fetches the next result row.

Returns true if there was one more row to be fetched.

Implemented in Wt::Dbo::backend::MySQLStatement.

use()

bool Wt::Dbo::SqlStatement::use

(

)

Uses the statement.

Marks the statement as in-use. If the statement is already in use, return false. In that case, we will later provision that a statement can be cloned and that a list of equivalent statement is kept in the statement cache of a connectin.