WiredTiger Python API

Python wrappers aroung the WiredTiger C API. More...

Classes
class	wiredtiger.Cursor
	Python wrapper around C WT_CURSOR. More...
class	wiredtiger.Session
	Python wrapper around C WT_SESSION. More...
class	wiredtiger.Connection
	Python wrapper around C WT_CONNECTION. More...

Functions
def	wiredtiger.wiredtiger_open
	wiredtiger_open(home, config) -> int
def	wiredtiger.wiredtiger_strerror
	wiredtiger_strerror(err) -> string
def	wiredtiger.wiredtiger_version
	wiredtiger_version() -> string

Variables
	wiredtiger.WiredTigerError
	wiredtiger.WIREDTIGER_VERSION_MAJOR
	wiredtiger.WIREDTIGER_VERSION_MINOR
	wiredtiger.WIREDTIGER_VERSION_PATCH
	wiredtiger.WIREDTIGER_VERSION_STRING
	wiredtiger.Cursor_swigregister
	wiredtiger.Session_swigregister
	wiredtiger.Connection_swigregister
	wiredtiger.WT_DEADLOCK
	wiredtiger.WT_DUPLICATE_KEY
	wiredtiger.WT_ERROR
	wiredtiger.WT_NOTFOUND
	wiredtiger.WT_RESTART
	wiredtiger.WT_STAT_CONN_BLOCK_READ
	wiredtiger.WT_STAT_CONN_BLOCK_WRITE
	wiredtiger.WT_STAT_CONN_CACHE_BYTES_INUSE
	wiredtiger.WT_STAT_CONN_CACHE_BYTES_MAX
	wiredtiger.WT_STAT_CONN_CACHE_EVICT_HAZARD
	wiredtiger.WT_STAT_CONN_CACHE_EVICT_INTERNAL
	wiredtiger.WT_STAT_CONN_CACHE_EVICT_MODIFIED
	wiredtiger.WT_STAT_CONN_CACHE_EVICT_SLOW
	wiredtiger.WT_STAT_CONN_CACHE_EVICT_UNMODIFIED
	wiredtiger.WT_STAT_CONN_CACHE_PAGES_INUSE
	wiredtiger.WT_STAT_CONN_CHECKPOINT
	wiredtiger.WT_STAT_CONN_COND_WAIT
	wiredtiger.WT_STAT_CONN_FILE_OPEN
	wiredtiger.WT_STAT_CONN_MEMALLOC
	wiredtiger.WT_STAT_CONN_MEMFREE
	wiredtiger.WT_STAT_CONN_RWLOCK_RDLOCK
	wiredtiger.WT_STAT_CONN_RWLOCK_WRLOCK
	wiredtiger.WT_STAT_CONN_TOTAL_READ_IO
	wiredtiger.WT_STAT_CONN_TOTAL_WRITE_IO
	wiredtiger.WT_STAT_CONN_TXN_ANCIENT
	wiredtiger.WT_STAT_CONN_TXN_BEGIN
	wiredtiger.WT_STAT_CONN_TXN_COMMIT
	wiredtiger.WT_STAT_CONN_TXN_FAIL_CACHE
	wiredtiger.WT_STAT_CONN_TXN_ROLLBACK
	wiredtiger.WT_STAT_DSRC_BLOCK_ALLOC
	wiredtiger.WT_STAT_DSRC_BLOCK_EXTEND
	wiredtiger.WT_STAT_DSRC_BLOCK_FREE
	wiredtiger.WT_STAT_DSRC_BLOOM_COUNT
	wiredtiger.WT_STAT_DSRC_BLOOM_FALSE_POSITIVE
	wiredtiger.WT_STAT_DSRC_BLOOM_HIT
	wiredtiger.WT_STAT_DSRC_BLOOM_MISS
	wiredtiger.WT_STAT_DSRC_BLOOM_PAGE_EVICT
	wiredtiger.WT_STAT_DSRC_BLOOM_PAGE_READ
	wiredtiger.WT_STAT_DSRC_BLOOM_SIZE
	wiredtiger.WT_STAT_DSRC_CKPT_SIZE
	wiredtiger.WT_STAT_DSRC_CURSOR_INSERT
	wiredtiger.WT_STAT_DSRC_CURSOR_READ
	wiredtiger.WT_STAT_DSRC_CURSOR_READ_NEAR
	wiredtiger.WT_STAT_DSRC_CURSOR_READ_NEXT
	wiredtiger.WT_STAT_DSRC_CURSOR_READ_PREV
	wiredtiger.WT_STAT_DSRC_CURSOR_REMOVE
	wiredtiger.WT_STAT_DSRC_CURSOR_RESET
	wiredtiger.WT_STAT_DSRC_CURSOR_UPDATE
	wiredtiger.WT_STAT_DSRC_ENTRIES
	wiredtiger.WT_STAT_DSRC_FILE_ALLOCSIZE
	wiredtiger.WT_STAT_DSRC_FILE_BULK_LOADED
	wiredtiger.WT_STAT_DSRC_FILE_COMPACT_REWRITE
	wiredtiger.WT_STAT_DSRC_FILE_FIXED_LEN
	wiredtiger.WT_STAT_DSRC_FILE_MAGIC
	wiredtiger.WT_STAT_DSRC_FILE_MAJOR
	wiredtiger.WT_STAT_DSRC_FILE_MAXINTLITEM
	wiredtiger.WT_STAT_DSRC_FILE_MAXINTLPAGE
	wiredtiger.WT_STAT_DSRC_FILE_MAXLEAFITEM
	wiredtiger.WT_STAT_DSRC_FILE_MAXLEAFPAGE
	wiredtiger.WT_STAT_DSRC_FILE_MINOR
	wiredtiger.WT_STAT_DSRC_FILE_SIZE
	wiredtiger.WT_STAT_DSRC_LSM_CHUNK_COUNT
	wiredtiger.WT_STAT_DSRC_LSM_GENERATION_MAX
	wiredtiger.WT_STAT_DSRC_LSM_LOOKUP_NO_BLOOM
	wiredtiger.WT_STAT_DSRC_OVERFLOW_PAGE
	wiredtiger.WT_STAT_DSRC_OVERFLOW_READ
	wiredtiger.WT_STAT_DSRC_OVERFLOW_VALUE_CACHE
	wiredtiger.WT_STAT_DSRC_PAGE_COL_DELETED
	wiredtiger.WT_STAT_DSRC_PAGE_COL_FIX
	wiredtiger.WT_STAT_DSRC_PAGE_COL_INT
	wiredtiger.WT_STAT_DSRC_PAGE_COL_VAR
	wiredtiger.WT_STAT_DSRC_PAGE_EVICT
	wiredtiger.WT_STAT_DSRC_PAGE_EVICT_FAIL
	wiredtiger.WT_STAT_DSRC_PAGE_READ
	wiredtiger.WT_STAT_DSRC_PAGE_ROW_INT
	wiredtiger.WT_STAT_DSRC_PAGE_ROW_LEAF
	wiredtiger.WT_STAT_DSRC_PAGE_WRITE
	wiredtiger.WT_STAT_DSRC_REC_DICTIONARY
	wiredtiger.WT_STAT_DSRC_REC_HAZARD
	wiredtiger.WT_STAT_DSRC_REC_OVFL_KEY
	wiredtiger.WT_STAT_DSRC_REC_OVFL_VALUE
	wiredtiger.WT_STAT_DSRC_REC_PAGE_DELETE
	wiredtiger.WT_STAT_DSRC_REC_PAGE_MERGE
	wiredtiger.WT_STAT_DSRC_REC_SPLIT_INTL
	wiredtiger.WT_STAT_DSRC_REC_SPLIT_LEAF
	wiredtiger.WT_STAT_DSRC_REC_WRITTEN
	wiredtiger.WT_STAT_DSRC_TXN_UPDATE_CONFLICT
	wiredtiger.WT_STAT_DSRC_TXN_WRITE_CONFLICT

Detailed Description

Python wrappers aroung the WiredTiger C API.

Function Documentation

def wiredtiger.wiredtiger_open

(

args

)

wiredtiger_open(home, config) -> int

Open a connection to a database.

        WT_CONNECTION *conn;

        ret = wiredtiger_open(
            "WiredTigerHome", NULL, "create,transactional", &conn);

Parameters

home	The path to the database home directory. See Database Home Directory for more information.
errhandler	An error handler. If NULL, a builtin error handler is installed that writes error messages to stderr
config	Configuration string, see Configuration Strings. Permitted values: Name Effect Values buffer_alignment in-memory alignment (in bytes) for buffers used for I/O. The default value of -1 indicates that a platform-specific alignment value should be used (512 bytes on Linux systems, zero elsewhere). an integer between -1 and 1MB; default -1. cache_size maximum heap memory to allocate for the cache. A database should configure either a cache_size or a shared_cache not both. an integer between 1MB and 10TB; default 100MB. create create the database if it does not exist. a boolean flag; default false. direct_io Use O_DIRECT to access files. Options are given as a list, such as "direct_io=[data]". a list, with values chosen from the following options: "data", "log"; default empty. error_prefix prefix string for error messages. a string; default empty. eviction_target continue evicting until the cache becomes less full than this (as a percentage). Must be less than eviction_trigger. an integer between 10 and 99; default 80. eviction_trigger trigger eviction when the cache becomes this full (as a percentage). an integer between 10 and 99; default 95. extensions list of shared library extensions to load (using dlopen). Optional values are passed as the config parameter to WT_CONNECTION::load_extension. Complex paths may require quoting, for example, extensions=("/path/ext.so"="entry=my_entry"). a list of strings; default empty. hazard_max maximum number of simultaneous hazard references per session handle. an integer greater than or equal to 15; default 1000. logging enable logging. a boolean flag; default false. lsm_merge merge LSM chunks where possible. a boolean flag; default true. multiprocess permit sharing between processes (will automatically start an RPC server for primary processes and use RPC for secondary processes). Not yet supported in WiredTiger. a boolean flag; default false. session_max maximum expected number of sessions (including server threads). an integer greater than or equal to 1; default 50. shared_cache = ( shared cache configuration options. A database should configure either a cache_size or a shared_cache not both. a set of related configuration options defined below.     chunk the granularity that a shared cache is redistributed. an integer between 1MB and 10TB; default 10MB.     min minimum amount of cache a database in a shared cache can have. an integer between 10MB and 10TB; default 50MB.     name name of a cache that is shared between databases. a string; default empty.     size maximum memory to allocate for the shared cache. an integer between 1MB and 10TB; default 500MB. ) sync flush files to stable storage when closing or writing checkpoints. a boolean flag; default true. transactional support transactional semantics. a boolean flag; default true. use_environment_priv use the WIREDTIGER_CONFIG and WIREDTIGER_HOME environment variables regardless of whether or not the process is running with special privileges. See Database Home Directory for more information. a boolean flag; default false. verbose enable messages for various events. Options are given as a list, such as "verbose=[evictserver,read]". a list, with values chosen from the following options: "block", "shared_cache", "ckpt", "evict", "evictserver", "fileops", "hazard", "lsm", "mutex", "read", "readserver", "reconcile", "salvage", "verify", "write"; default empty. Additionally, if a file named WiredTiger.config appears in the WiredTiger home directory, it is read for configuration values (see WiredTiger.config file for details). Configuration values specified in the config argument to the wiredtiger_open function override configuration values specified in the WiredTiger.config file.
connectionp	A pointer to the newly opened connection handle

Returns

zero on success and a non-zero error code on failure. See Error Returns for details.

def wiredtiger.wiredtiger_strerror

(

args

)

wiredtiger_strerror(err) -> string

Return information about an error as a string; wiredtiger_strerror is a superset of the ISO C99/POSIX 1003.1-2001 function strerror.

        const char *key = "some key";
        cursor->set_key(cursor, key);
        if ((ret = cursor->remove(cursor)) != 0) {
                fprintf(stderr,
                    "cursor.remove: %s\n", wiredtiger_strerror(ret));
                return (ret);
        }

Parameters

err	a return value from a WiredTiger, C library or POSIX function

Returns

a string representation of the error

def wiredtiger.wiredtiger_version

(

)

wiredtiger_version() -> string

Get version information.

        printf("WiredTiger version %s\n", wiredtiger_version(NULL, NULL, NULL));

        int major, minor, patch;
        (void)wiredtiger_version(&major, &minor, &patch);
        printf("WiredTiger version is %d, %d (patch %d)\n",
            major, minor, patch);

Parameters

majorp	a location where the major version number is returned
minorp	a location where the minor version number is returned
patchp	a location where the patch version number is returned

Returns

a string representation of the version