WT_ASYNC_OP Struct Reference

A WT_ASYNC_OP handle is the interface to an asynchronous operation. More...

Public Member Functions
uint64_t	get_id (WT_ASYNC_OP *op)
	Get the unique identifier for this operation. More...
WT_ASYNC_OPTYPE	get_type (WT_ASYNC_OP *op)
	Get the type for this operation. More...
Data access
int	get_key (WT_ASYNC_OP *op,...)
	Invoke the underlying WT_CURSOR::get_key method; see that method for configuration, return and error values. More...
int	get_value (WT_ASYNC_OP *op,...)
	Invoke the underlying WT_CURSOR::get_value method; see that method for configuration, return and error values. More...
void	set_key (WT_ASYNC_OP *op,...)
	Invoke the underlying WT_CURSOR::set_key method; see that method for configuration, return and error values. More...
void	set_value (WT_ASYNC_OP *op,...)
	Invoke the underlying WT_CURSOR::set_value method; see that method for configuration, return and error values. More...
Positioning
int	search (WT_ASYNC_OP *op)
	Invoke the underlying WT_CURSOR::search method; see that method for configuration, return and error values. More...
Data modification
int	insert (WT_ASYNC_OP *op)
	Invoke the underlying WT_CURSOR::insert method; see that method for configuration, return and error values. More...
int	update (WT_ASYNC_OP *op)
	Invoke the underlying WT_CURSOR::update method; see that method for configuration, return and error values. More...
int	remove (WT_ASYNC_OP *op)
	Invoke the underlying WT_CURSOR::remove method; see that method for configuration, return and error values. More...
Table operations
int	compact (WT_ASYNC_OP *op)
	Invoke the underlying WT_SESSION::compact method; see that method for configuration, return and error values. More...

Public Attributes
WT_CONNECTION *	connection
	The connection for this operation. More...
const char *	key_format
	The format of the data packed into key items. More...
const char *	value_format
	The format of the data packed into value items. More...
void *	app_private
	A location for applications to store information that will be available in the callback from an async operation.

Detailed Description

A WT_ASYNC_OP handle is the interface to an asynchronous operation.

An asynchronous operation describes a data manipulation to be performed asynchronously by a WiredTiger worker thread. These operations implement the CRUD (create, read, update and delete) operations. Each operation is a self-contained work unit. The operation will be performed in the context of the worker thread's session. Each operation is performed within the context of a transaction. The application is notified of its completion with a callback. The transaction is resolved once the callback returns.

The table referenced in an operation must already exist.

Raw data is represented by key/value pairs of WT_ITEM structures, but operations can also provide access to fields within the key and value if the formats are described in the WT_SESSION::create method.

Thread safety: A WT_ASYNC_OP handle may not be shared between threads, see Multithreading for more information.

Examples:

ex_async.c.

Member Function Documentation

int WT_ASYNC_OP::compact

(

WT_ASYNC_OP *

op

)

Invoke the underlying WT_SESSION::compact method; see that method for configuration, return and error values.

Parameters

op	the operation handle

Returns

via the callback as described for WT_SESSION::compact

Examples:

ex_async.c.

uint64_t WT_ASYNC_OP::get_id

(

WT_ASYNC_OP *

op

)

Get the unique identifier for this operation.

        /* Retrieve the operation's 64-bit identifier. */
        id = op->get_id(op);

Parameters

op	the operation handle

Returns

the id of the operation

Examples:

ex_async.c.

int WT_ASYNC_OP::get_key	(	WT_ASYNC_OP *	op,
			...
	)

Invoke the underlying WT_CURSOR::get_key method; see that method for configuration, return and error values.

Parameters

op	the operation handle

Returns

as described for WT_CURSOR::get_key

Examples:

ex_async.c.

WT_ASYNC_OPTYPE WT_ASYNC_OP::get_type

(

WT_ASYNC_OP *

op

)

Get the type for this operation.

        /* Retrieve the operation's WT_ASYNC_OPTYPE type. */
        type = op->get_type(op);

Parameters

op	the operation handle

Returns

the WT_ASYNC_OPTYPE of the operation

Examples:

ex_async.c.

int WT_ASYNC_OP::get_value	(	WT_ASYNC_OP *	op,
			...
	)

Invoke the underlying WT_CURSOR::get_value method; see that method for configuration, return and error values.

Parameters

op	the operation handle

Returns

as described for WT_CURSOR::get_value

Examples:

ex_async.c.

int WT_ASYNC_OP::insert

(

WT_ASYNC_OP *

op

)

Invoke the underlying WT_CURSOR::insert method; see that method for configuration, return and error values.

Parameters

op	the operation handle

Returns

via the callback as described for WT_CURSOR::insert

Examples:

ex_async.c.

int WT_ASYNC_OP::remove

(

WT_ASYNC_OP *

op

)

Invoke the underlying WT_CURSOR::remove method; see that method for configuration, return and error values.

Parameters

op	the operation handle

Returns

via the callback as described for WT_CURSOR::remove

int WT_ASYNC_OP::search

(

WT_ASYNC_OP *

op

)

Invoke the underlying WT_CURSOR::search method; see that method for configuration, return and error values.

Parameters

op	the operation handle

Returns

via the callback as described for WT_CURSOR::search

Examples:

ex_async.c.

void WT_ASYNC_OP::set_key	(	WT_ASYNC_OP *	op,
			...
	)

Invoke the underlying WT_CURSOR::set_key method; see that method for configuration, return and error values.

Parameters

op	the operation handle

Examples:

ex_async.c.

void WT_ASYNC_OP::set_value	(	WT_ASYNC_OP *	op,
			...
	)

Invoke the underlying WT_CURSOR::set_value method; see that method for configuration, return and error values.

Parameters

op	the operation handle

Examples:

ex_async.c.

int WT_ASYNC_OP::update

(

WT_ASYNC_OP *

op

)

Invoke the underlying WT_CURSOR::update method; see that method for configuration, return and error values.

Parameters

op	the operation handle

Returns

via the callback as described for WT_CURSOR::update

Member Data Documentation

WT_CONNECTION* WT_ASYNC_OP::connection

The connection for this operation.

const char* WT_ASYNC_OP::key_format

The format of the data packed into key items.

See Packing and Unpacking Data for details. If not set, a default value of "u" is assumed, and applications must use WT_ITEM structures to manipulate untyped byte arrays.

const char* WT_ASYNC_OP::value_format

The format of the data packed into value items.

See Packing and Unpacking Data for details. If not set, a default value of "u" is assumed, and applications must use WT_ITEM structures to manipulate untyped byte arrays.