Statement Class Reference

#include <Pt/Db/Statement.h>

Prepared SQL statement with named host variables. More...

Public Types
typedef IStatement::size_type	size_type
	Size type of this statement.

Public Member Functions
	Statement (IStatement *stmt=0)
	Takes ownership of the backend stmt.
Statement &	clear ()
	Sets all host variables to NULL.
Statement &	setNull (const std::string &col)
	Sets the host variable col to NULL.
Statement &	set (const std::string &col, bool data)
	Sets the host variable col to data.
Statement &	set (const std::string &col, int data)
	Sets the host variable col to data.
Statement &	set (const std::string &col, unsigned data)
	Sets the host variable col to data.
Statement &	set (const std::string &col, float data)
	Sets the host variable col to data.
Statement &	set (const std::string &col, double data)
	Sets the host variable col to data.
Statement &	set (const std::string &col, char data)
	Sets the host variable col to data.
Statement &	set (const std::string &col, const std::string &data)
	Sets the host variable col to data.
Statement &	set (const std::string &col, const Blob &data)
	Sets the host variable col to data.
Statement &	set (const std::string &col, const char *data)
	Sets the host variable col to data, or to NULL if data is 0.
Statement &	set (const std::string &col, const Date &data)
	Sets the host variable col to data.
Statement &	set (const std::string &col, const Time &data)
	Sets the host variable col to data.
Statement &	set (const std::string &col, const DateTime &data)
	Sets the host variable col to data.
Cursor	getCursor (size_type batchSize)
	Opens a batch cursor that fetches batchSize rows at a time.
void	cancel ()
	Cancels any pending asynchronous operation.
size_type	execute ()
	Executes the statement and returns the number of rows changed.
void	beginExecute ()
	Starts asynchronous execution.
size_type	endExecute ()
	Completes asynchronous execution.
Signal &	executeFinished ()
	Signal emitted when asynchronous execution completes.
long long	lastInsertId () const
	Returns the generated row id of the last insert.
Result	select ()
	Executes the statement and returns a buffered result.
Row	selectRow ()
	Executes the statement and returns the first row.
Value	selectValue ()
	Executes the statement and returns the first column of the first row.
void	beginSelect ()
	Starts an asynchronous select.
Result	endSelect ()
	Completes an asynchronous select.
Signal &	selectFinished ()
	Signal emitted when an asynchronous select completes.
bool	operator! () const
	Returns true if this object is not bound to a statement.
const IStatement *	getImpl () const
	Returns the backend implementation.
IStatement *	impl ()
	Returns the backend implementation.

Detailed Description

Statement is the compiled query the group described. Obtain it from Connection::prepare() or Connection::prepareCached(). It is a shared value. An unbound statement is empty; operator!() is true then. The constructor that takes an IStatement takes ownership of that backend.

Host variables are :name. Bind them with set() before execute or select. setNull() binds SQL NULL. clear() sets every host variable to NULL. A const char pointer that is 0 is bound as NULL.

execute() runs a statement that does not return rows and returns how many rows changed. lastInsertId() is the generated id after that execute. select() returns a buffered Result. selectRow() returns the first row and discards the rest. selectValue() returns the first column of the first row. Both throw InvalidQuery when the query returns no row.

getCursor() opens a batch cursor on this statement. beginExecute() / endExecute() / executeFinished() and beginSelect() / endSelect() / selectFinished() are the async forms. cancel() aborts a pending operation.

Pt::Db::Statement stmt = conn.prepare(
    "SELECT name FROM users WHERE id = :id");
stmt.set("id", 1);
Pt::Db::Value name = stmt.selectValue();

Member Function Documentation

clear()

Statement & clear

(

)

Returns

This statement.

setNull()

Statement & setNull

(

const std::string &

col

)

Returns

This statement.

set() [1/12]

Statement & set	(	const std::string &	col,
		bool	data )

Returns

This statement.

set() [2/12]

Statement & set	(	const std::string &	col,
		int	data )

Returns

This statement.

set() [3/12]

Statement & set	(	const std::string &	col,
		unsigned	data )

Returns

This statement.

set() [4/12]

Statement & set	(	const std::string &	col,
		float	data )

Returns

This statement.

set() [5/12]

Statement & set	(	const std::string &	col,
		double	data )

Returns

This statement.

set() [6/12]

Statement & set	(	const std::string &	col,
		char	data )

Returns

This statement.

set() [7/12]

Statement & set	(	const std::string &	col,
		const std::string &	data )

Returns

This statement.

set() [8/12]

Statement & set	(	const std::string &	col,
		const Blob &	data )

Returns

This statement.

set() [9/12]

Statement & set	(	const std::string &	col,
		const char *	data )

Returns

This statement.

set() [10/12]

Statement & set	(	const std::string &	col,
		const Date &	data )

Returns

This statement.

set() [11/12]

Statement & set	(	const std::string &	col,
		const Time &	data )

Returns

This statement.

set() [12/12]

Statement & set	(	const std::string &	col,
		const DateTime &	data )

Returns

This statement.

endExecute()

size_type endExecute

(

)

Returns

Number of rows changed.

selectRow()

Row selectRow

(

)

Additional rows are discarded.

Exceptions

%InvalidQuery

if the query returns no row.

selectValue()

Value selectValue

(

)

Exceptions

%InvalidQuery

if the query returns no row.

endSelect()

Result endSelect

(

)

Returns

Buffered result of the query.