hamsterdb Transaction Functions

Defines
#define	HAM_TXN_READ_ONLY   1
Typedefs
typedef struct ham_txn_t	ham_txn_t
Functions
ham_status_t	ham_txn_begin (ham_txn_t **txn, ham_db_t *db, ham_u32_t flags)
ham_status_t	ham_txn_commit (ham_txn_t *txn, ham_u32_t flags)
ham_status_t	ham_txn_abort (ham_txn_t *txn, ham_u32_t flags)

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Define Documentation

#define HAM_TXN_READ_ONLY   1

Flag for ham_txn_begin

Definition at line 819 of file hamsterdb.h.

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Typedef Documentation

typedef struct ham_txn_t ham_txn_t

Definition at line 792 of file hamsterdb.h.

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Function Documentation

ham_status_t ham_txn_abort	(	ham_txn_t *	txn,
		ham_u32_t	flags
	)

Aborts a Transaction

Remarks:

Note that the function will fail with HAM_CURSOR_STILL_OPEN if a Cursor was attached to this Transaction (with ham_cursor_create or ham_cursor_clone), and the Cursor was not closed.

Parameters:

	db	Pointer to a Transaction structure
	flags	Optional flags for aborting the Transaction, combined with bitwise OR. Unused, set to 0.

Returns:

HAM_SUCCESS upon success

HAM_IO_ERROR if writing to the Database file or logfile failed

HAM_CURSOR_STILL_OPEN if there are Cursors attached to this Transaction

Referenced by ham::txn::abort().

ham_status_t ham_txn_begin	(	ham_txn_t **	txn,
		ham_db_t *	db,
		ham_u32_t	flags
	)

Begins a new Transaction

Parameters:

	db	Pointer to a pointer of a Transaction structure
	flags	Optional flags for beginning the Transaction, combined with bitwise OR. Possible flags are: HAM_TXN_READ_ONLY This Transaction is read-only and will not modify the Database.

Note:

Note that as of hamsterdb 1.0.4, it is not possible to create multiple Transactions in parallel. This limitation will be removed in further versions.

Returns:

HAM_SUCCESS upon success

HAM_OUT_OF_MEMORY if memory allocation failed

HAM_LIMITS_REACHED if there's already an open Transaction (see above)

Referenced by ham::db::begin().

ham_status_t ham_txn_commit	(	ham_txn_t *	txn,
		ham_u32_t	flags
	)

Commits a Transaction

Remarks:

Note that the function will fail with HAM_CURSOR_STILL_OPEN if a Cursor was attached to this Transaction (with ham_cursor_create or ham_cursor_clone), and the Cursor was not closed.

Parameters:

	db	Pointer to a Transaction structure
	flags	Optional flags for committing the Transaction, combined with bitwise OR. Unused, set to 0.

Returns:

HAM_SUCCESS upon success

HAM_IO_ERROR if writing to the file failed

HAM_CURSOR_STILL_OPEN if there are Cursors attached to this Transaction

Referenced by ham::txn::commit().