Class | TokyoCabinet::FDB |
In: |
tokyocabinet.c
tokyocabinet-doc.rb |
Parent: | Object |
Fixed-Length database is a file containing a fixed-length table and is handled with the fixed-length database API. Before operations to store or retrieve records, it is necessary to open a database file and connect the fixed-length database object to it. To avoid data missing or corruption, it is important to close every database file when it is no longer in use. It is forbidden for multible database objects in a process to open the same database at the same time.%% Except for the interface below, methods compatible with the `Hash’ class are also provided; `[]’, `[]=’, `store’, `delete’, `fetch’, `has_key?’, `has_value?’, `key’, `clear’, `length’, `empty?’, `each’, `each_key’, `each_value’, and `keys’.%%
ESUCCESS | = | INT2NUM(TCESUCCESS) | ||
ETHREAD | = | INT2NUM(TCETHREAD) | ||
EINVALID | = | INT2NUM(TCEINVALID) | ||
ENOFILE | = | INT2NUM(TCENOFILE) | ||
ENOPERM | = | INT2NUM(TCENOPERM) | ||
EMETA | = | INT2NUM(TCEMETA) | ||
ERHEAD | = | INT2NUM(TCERHEAD) | ||
EOPEN | = | INT2NUM(TCEOPEN) | ||
ECLOSE | = | INT2NUM(TCECLOSE) | ||
ETRUNC | = | INT2NUM(TCETRUNC) | ||
ESYNC | = | INT2NUM(TCESYNC) | ||
ESTAT | = | INT2NUM(TCESTAT) | ||
ESEEK | = | INT2NUM(TCESEEK) | ||
EREAD | = | INT2NUM(TCEREAD) | ||
EWRITE | = | INT2NUM(TCEWRITE) | ||
EMMAP | = | INT2NUM(TCEMMAP) | ||
ELOCK | = | INT2NUM(TCELOCK) | ||
EUNLINK | = | INT2NUM(TCEUNLINK) | ||
ERENAME | = | INT2NUM(TCERENAME) | ||
EMKDIR | = | INT2NUM(TCEMKDIR) | ||
ERMDIR | = | INT2NUM(TCERMDIR) | ||
EKEEP | = | INT2NUM(TCEKEEP) | ||
ENOREC | = | INT2NUM(TCENOREC) | ||
EMISC | = | INT2NUM(TCEMISC) | ||
OREADER | = | INT2NUM(FDBOREADER) | ||
OWRITER | = | INT2NUM(FDBOWRITER) | ||
OCREAT | = | INT2NUM(FDBOCREAT) | ||
OTRUNC | = | INT2NUM(FDBOTRUNC) | ||
ONOLCK | = | INT2NUM(FDBONOLCK) | ||
OLCKNB | = | INT2NUM(FDBOLCKNB) | ||
ESUCCESS | = | 0 | error code: success | |
ETHREAD | = | 1 | error code: threading error | |
EINVALID | = | 2 | error code: invalid operation | |
ENOFILE | = | 3 | error code: file not found | |
ENOPERM | = | 4 | error code: no permission | |
EMETA | = | 5 | error code: invalid meta data | |
ERHEAD | = | 6 | error code: invalid record header | |
EOPEN | = | 7 | error code: open error | |
ECLOSE | = | 8 | error code: close error | |
ETRUNC | = | 9 | error code: trunc error | |
ESYNC | = | 10 | error code: sync error | |
ESTAT | = | 11 | error code: stat error | |
ESEEK | = | 12 | error code: seek error | |
EREAD | = | 13 | error code: read error | |
EWRITE | = | 14 | error code: write error | |
EMMAP | = | 15 | error code: mmap error | |
ELOCK | = | 16 | error code: lock error | |
EUNLINK | = | 17 | error code: unlink error | |
ERENAME | = | 18 | error code: rename error | |
EMKDIR | = | 19 | error code: mkdir error | |
ERMDIR | = | 20 | error code: rmdir error | |
EKEEP | = | 21 | error code: existing record | |
ENOREC | = | 22 | error code: no record found | |
EMISC | = | 9999 | error code: miscellaneous error | |
OREADER | = | 1 << 0 | open mode: open as a reader | |
OWRITER | = | 1 << 1 | open mode: open as a writer | |
OCREAT | = | 1 << 2 | open mode: writer creating | |
OTRUNC | = | 1 << 3 | open mode: writer truncating | |
ONOLCK | = | 1 << 4 | open mode: open without locking | |
OLCKNB | = | 1 << 5 | open mode: lock without blocking |
Add a real number to a record.%% `key’ specifies the key. It should be more than 0. If it is "min", the minimum ID number of existing records is specified. If it is "prev", the number less by one than the minimum ID number of existing records is specified. If it is "max", the maximum ID number of existing records is specified. If it is "next", the number greater by one than the maximum ID number of existing records is specified.%% `num’ specifies the additional value.%% If successful, the return value is the summation value, else, it is `nil’.%% If the corresponding record exists, the value is treated as a real number and is added to. If no record corresponds, a new record of the additional value is stored. Because records are stored in binary format, they should be processed with the `unpack’ method with the `d’ operator after retrieval.%%
# File tokyocabinet-doc.rb, line 871 871: def adddouble(key, num) 872: # (native code) 873: end
Add an integer to a record.%% `key’ specifies the key. It should be more than 0. If it is "min", the minimum ID number of existing records is specified. If it is "prev", the number less by one than the minimum ID number of existing records is specified. If it is "max", the maximum ID number of existing records is specified. If it is "next", the number greater by one than the maximum ID number of existing records is specified.%% `num’ specifies the additional value.%% If successful, the return value is the summation value, else, it is `nil’.%% If the corresponding record exists, the value is treated as an integer and is added to. If no record corresponds, a new record of the additional value is stored. Because records are stored in binary format, they should be processed with the `unpack’ method with the `i’ operator after retrieval.%%
# File tokyocabinet-doc.rb, line 863 863: def addint(key, num) 864: # (native code) 865: end
Close the database file.%% If successful, the return value is true, else, it is false.%% Update of a database is assured to be written when the database is closed. If a writer opens a database but does not close it appropriately, the database will be broken.%%
# File tokyocabinet-doc.rb, line 794 794: def close() 795: # (native code) 796: end
Copy the database file.%% `path’ specifies the path of the destination file. If it begins with `@’, the trailing substring is executed as a command line.%% If successful, the return value is true, else, it is false. False is returned if the executed command returns non-zero code.%% The database file is assured to be kept synchronized and not modified while the copying or executing operation is in progress. So, this method is useful to create a backup file of the database file.%%
# File tokyocabinet-doc.rb, line 896 896: def copy(path) 897: # (native code) 898: end
Get the last happened error code.%% The return value is the last happened error code.%% The following error codes are defined: `TokyoCabinet::FDB::ESUCCESS’ for success, `TokyoCabinet::FDB::ETHREAD’ for threading error, `TokyoCabinet::FDB::EINVALID’ for invalid operation, `TokyoCabinet::FDB::ENOFILE’ for file not found, `TokyoCabinet::FDB::ENOPERM’ for no permission, `TokyoCabinet::FDB::EMETA’ for invalid meta data, `TokyoCabinet::FDB::ERHEAD’ for invalid record header, `TokyoCabinet::FDB::EOPEN’ for open error, `TokyoCabinet::FDB::ECLOSE’ for close error, `TokyoCabinet::FDB::ETRUNC’ for trunc error, `TokyoCabinet::FDB::ESYNC’ for sync error, `TokyoCabinet::FDB::ESTAT’ for stat error, `TokyoCabinet::FDB::ESEEK’ for seek error, `TokyoCabinet::FDB::EREAD’ for read error, `TokyoCabinet::FDB::EWRITE’ for write error, `TokyoCabinet::FDB::EMMAP’ for mmap error, `TokyoCabinet::FDB::ELOCK’ for lock error, `TokyoCabinet::FDB::EUNLINK’ for unlink error, `TokyoCabinet::FDB::ERENAME’ for rename error, `TokyoCabinet::FDB::EMKDIR’ for mkdir error, `TokyoCabinet::FDB::ERMDIR’ for rmdir error, `TokyoCabinet::FDB::EKEEP’ for existing record, `TokyoCabinet::FDB::ENOREC’ for no record found, and `TokyoCabinet::FDB::EMISC’ for miscellaneous error.%%
# File tokyocabinet-doc.rb, line 774 774: def ecode() 775: # (native code) 776: end
Get the message string corresponding to an error code.%% `ecode’ specifies the error code. If it is not defined or negative, the last happened error code is specified.%% The return value is the message string of the error code.%%
# File tokyocabinet-doc.rb, line 768 768: def errmsg(ecode) 769: # (native code) 770: end
Get the size of the database file.%% The return value is the size of the database file or 0 if the object does not connect to any database file.%%
# File tokyocabinet-doc.rb, line 929 929: def fsiz() 930: # (native code) 931: end
Retrieve a record.%% `key’ specifies the key. It should be more than 0. If it is `FDBIDMIN’, the minimum ID number of existing records is specified. If it is `FDBIDMAX’, the maximum ID number of existing records is specified.%% If successful, the return value is the value of the corresponding record. `nil’ is returned if no record corresponds.%%
# File tokyocabinet-doc.rb, line 830 830: def get(key) 831: # (native code) 832: end
Initialize the iterator.%% If successful, the return value is true, else, it is false.%% The iterator is used in order to access the key of every record stored in a database.%%
# File tokyocabinet-doc.rb, line 842 842: def iterinit() 843: # (native code) 844: end
Get the next key of the iterator.%% If successful, the return value is the next key, else, it is `nil’. `nil’ is returned when no record is to be get out of the iterator.%% It is possible to access every record by iteration of calling this method. It is allowed to update or remove records whose keys are fetched while the iteration. The order of this traversal access method is ascending of the ID number.%%
# File tokyocabinet-doc.rb, line 848 848: def iternext() 849: # (native code) 850: end
Open a database file.%% `path’ specifies the path of the database file.%% `omode’ specifies the connection mode: `TokyoCabinet::FDB::OWRITER’ as a writer, `TokyoCabinet::FDB::OREADER’ as a reader. If the mode is `TokyoCabinet::FDB::OWRITER’, the following may be added by bitwise-or: `TokyoCabinet::FDB::OCREAT’, which means it creates a new database if not exist, `TokyoCabinet::FDB::OTRUNC’, which means it creates a new database regardless if one exists. Both of `TokyoCabinet::FDB::OREADER’ and `TokyoCabinet::FDB::OWRITER’ can be added to by bitwise-or: `TokyoCabinet::FDB::ONOLCK’, which means it opens the database file without file locking, or `TokyoCabinet::FDB::OLCKNB’, which means locking is performed without blocking. If it is not defined, `TokyoCabinet::FDB::OREADER’ is specified.%% If successful, the return value is true, else, it is false.%%
# File tokyocabinet-doc.rb, line 788 788: def open(path, omode) 789: # (native code) 790: end
Optimize the database file.%% `width’ specifies the width of the value of each record. If it is not defined or not more than 0, the current setting is not changed.%% `limsiz’ specifies the limit size of the database file. If it is not defined or not more than 0, the current setting is not changed.%% If successful, the return value is true, else, it is false.%%
# File tokyocabinet-doc.rb, line 884 884: def optimize(bnum, width, limsiz) 885: # (native code) 886: end
Remove a record.%% `key’ specifies the key. It should be more than 0. If it is `FDBIDMIN’, the minimum ID number of existing records is specified. If it is `FDBIDMAX’, the maximum ID number of existing records is specified.%% If successful, the return value is true, else, it is false.%%
# File tokyocabinet-doc.rb, line 824 824: def out(key) 825: # (native code) 826: end
Store a record.%% `key’ specifies the key. It should be more than 0. If it is "min", the minimum ID number of existing records is specified. If it is "prev", the number less by one than the minimum ID number of existing records is specified. If it is "max", the maximum ID number of existing records is specified. If it is "next", the number greater by one than the maximum ID number of existing records is specified.%% `value’ specifies the value.%% If successful, the return value is true, else, it is false.%% If a record with the same key exists in the database, it is overwritten.%%
# File tokyocabinet-doc.rb, line 802 802: def put(key, value) 803: # (native code) 804: end
Concatenate a value at the end of the existing record.%% `key’ specifies the key. It should be more than 0. If it is "min", the minimum ID number of existing records is specified. If it is "prev", the number less by one than the minimum ID number of existing records is specified. If it is "max", the maximum ID number of existing records is specified. If it is "next", the number greater by one than the maximum ID number of existing records is specified.%% `value’ specifies the value.%% If successful, the return value is true, else, it is false.%% If there is no corresponding record, a new record is created.%%
# File tokyocabinet-doc.rb, line 818 818: def putcat(key, value) 819: # (native code) 820: end
Store a new record.%% `key’ specifies the key. It should be more than 0. If it is "min", the minimum ID number of existing records is specified. If it is "prev", the number less by one than the minimum ID number of existing records is specified. If it is "max", the maximum ID number of existing records is specified. If it is "next", the number greater by one than the maximum ID number of existing records is specified.%% `value’ specifies the value.%% If successful, the return value is true, else, it is false.%% If a record with the same key exists in the database, this method has no effect.%%
# File tokyocabinet-doc.rb, line 810 810: def putkeep(key, value) 811: # (native code) 812: end
Get keys with an interval notation.%% `interval’ specifies the interval notation.%% `max’ specifies the maximum number of keys to be fetched. If it is not defined or negative, no limit is specified.%% The return value is a list object of the keys of the corresponding records. This method does never fail. It returns an empty list even if no record corresponds.%%
# File tokyocabinet-doc.rb, line 855 855: def range(interval, max) 856: # (native code) 857: end
Get the number of records.%% The return value is the number of records or 0 if the object does not connect to any database file.%%
# File tokyocabinet-doc.rb, line 924 924: def rnum() 925: # (native code) 926: end
Synchronize updated contents with the file and the device.%% If successful, the return value is true, else, it is false.%% This method is useful when another process connects the same database file.%%
# File tokyocabinet-doc.rb, line 877 877: def sync() 878: # (native code) 879: end
Abort the transaction.%% If successful, the return value is true, else, it is false.%% Update in the transaction is discarded when it is aborted. The state of the database is rollbacked to before transaction.%%
# File tokyocabinet-doc.rb, line 914 914: def tranabort() 915: # (native code) 916: end
Begin the transaction.%% If successful, the return value is true, else, it is false.%% The database is locked by the thread while the transaction so that only one transaction can be activated with a database object at the same time. Thus, the serializable isolation level is assumed if every database operation is performed in the transaction. All updated regions are kept track of by write ahead logging while the transaction. If the database is closed during transaction, the transaction is aborted implicitly.%%
# File tokyocabinet-doc.rb, line 902 902: def tranbegin() 903: # (native code) 904: end
Commit the transaction.%% If successful, the return value is true, else, it is false.%% Update in the transaction is fixed when it is committed successfully.%%
# File tokyocabinet-doc.rb, line 908 908: def trancommit() 909: # (native code) 910: end
Set the tuning parameters.%% `width’ specifies the width of the value of each record. If it is not defined or not more than 0, the default value is specified. The default value is 255.%% `limsiz’ specifies the limit size of the database file. If it is not defined or not more than 0, the default value is specified. The default value is 268435456.%% If successful, the return value is true, else, it is false. Note that the tuning parameters of the database should be set before the database is opened.%%
# File tokyocabinet-doc.rb, line 781 781: def tune(width, limsiz) 782: # (native code) 783: end
Remove all records.%% If successful, the return value is true, else, it is false.%%
# File tokyocabinet-doc.rb, line 889 889: def vanish() 890: # (native code) 891: end
Get the size of the value of a record.%% `key’ specifies the key. It should be more than 0. If it is `FDBIDMIN’, the minimum ID number of existing records is specified. If it is `FDBIDMAX’, the maximum ID number of existing records is specified.%% If successful, the return value is the size of the value of the corresponding record, else, it is -1.%%
# File tokyocabinet-doc.rb, line 836 836: def vsiz(key) 837: # (native code) 838: end