table of contents
TCTDB(3) | Tokyo Cabinet | TCTDB(3) |
NAME¶
tctdb - the table database APIDESCRIPTION¶
Table database is a file containing records composed of the primary keys and arbitrary columns and is handled with the table database API. To use the table database API, include ` tcutil.h', `tctdb.h', and related standard header files. Usually, write the following description near the front of a source file.API¶
The function `tctdberrmsg' is used in order to get the message string corresponding to an error code.`ecode' specifies the error code.
The return value is the message string of the error
code.
The return value is the new table database object.
`tdb' specifies the table database object.
If the database is not closed, it is closed implicitly.
Note that the deleted object and its derivatives can not be used
anymore.
`tdb' specifies the table database object.
The return value is the last happened error code.
The following error codes are defined: `TCESUCCESS' for
success, `TCETHREAD' for threading error, `TCEINVALID' for invalid operation,
`TCENOFILE' for file not found, `TCENOPERM' for no permission, `TCEMETA' for
invalid meta data, `TCERHEAD' for invalid record header, `TCEOPEN' for open
error, `TCECLOSE' for close error, `TCETRUNC' for trunc error, `TCESYNC' for
sync error, `TCESTAT' for stat error, `TCESEEK' for seek error, `TCEREAD' for
read error, `TCEWRITE' for write error, `TCEMMAP' for mmap error, `TCELOCK'
for lock error, `TCEUNLINK' for unlink error, `TCERENAME' for rename error,
`TCEMKDIR' for mkdir error, `TCERMDIR' for rmdir error, `TCEKEEP' for existing
record, `TCENOREC' for no record found, and `TCEMISC' for miscellaneous
error.
`tdb' specifies the table database object which is
not opened.
If successful, the return value is true, else, it is
false.
Note that the mutual exclusion control is needed if the
object is shared by plural threads and this function should be called before
the database is opened.
`tdb' specifies the table database object which is
not opened.
`bnum' specifies the number of elements of the
bucket array. If it is not more than 0, the default value is specified. The
default value is 131071. Suggested size of the bucket array is about from 0.5
to 4 times of the number of all records to be stored.
`apow' specifies the size of record alignment by
power of 2. If it is negative, the default value is specified. The default
value is 4 standing for 2^4=16.
`fpow' specifies the maximum number of elements of
the free block pool by power of 2. If it is negative, the default value is
specified. The default value is 10 standing for 2^10=1024.
`opts' specifies options by bitwise-or:
`TDBTLARGE' specifies that the size of the database can be larger than 2GB by
using 64-bit bucket array, `TDBTDEFLATE' specifies that each record is
compressed with Deflate encoding, `TDBTBZIP' specifies that each record is
compressed with BZIP2 encoding, `TDBTTCBS' specifies that each record is
compressed with TCBS encoding.
If successful, the return value is true, else, it is
false.
Note that the tuning parameters should be set before the
database is opened.
`tdb' specifies the table database object which is
not opened.
`rcnum' specifies the maximum number of records to
be cached. If it is not more than 0, the record cache is disabled. It is
disabled by default.
`lcnum' specifies the maximum number of leaf nodes
to be cached. If it is not more than 0, the default value is specified. The
default value is 4096.
`ncnum' specifies the maximum number of non-leaf
nodes to be cached. If it is not more than 0, the default value is specified.
The default value is 512.
If successful, the return value is true, else, it is
false.
Note that the caching parameters should be set before the
database is opened. Leaf nodes and non-leaf nodes are used in column
indices.
`tdb' specifies the table database object which is
not opened.
`xmsiz' specifies the size of the extra mapped
memory. If it is not more than 0, the extra mapped memory is disabled. The
default size is 67108864.
If successful, the return value is true, else, it is
false.
Note that the mapping parameters should be set before the
database is opened.
`tdb' specifies the table database object which is
not opened.
`dfunit' specifie the unit step number. If it is
not more than 0, the auto defragmentation is disabled. It is disabled by
default.
If successful, the return value is true, else, it is
false.
Note that the defragmentation parameters should be set
before the database is opened.
`tdb' specifies the table database object which is
not opened.
`path' specifies the path of the database
file.
`omode' specifies the connection mode:
`TDBOWRITER' as a writer, `TDBOREADER' as a reader. If the mode is
`TDBOWRITER', the following may be added by bitwise-or: `TDBOCREAT', which
means it creates a new database if not exist, `TDBOTRUNC', which means it
creates a new database regardless if one exists, `TDBOTSYNC', which means
every transaction synchronizes updated contents with the device. Both of
`TDBOREADER' and `TDBOWRITER' can be added to by bitwise-or: `TDBONOLCK',
which means it opens the database file without file locking, or `TDBOLCKNB',
which means locking is performed without blocking.
If successful, the return value is true, else, it is
false.
`tdb' specifies the table database object.
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.
`tdb' specifies the table database object
connected as a writer.
`pkbuf' specifies the pointer to the region of the
primary key.
`pksiz' specifies the size of the region of the
primary key.
`cols' specifies a map object containing
columns.
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.
`tdb' specifies the table database object
connected as a writer.
`pkbuf' specifies the pointer to the region of the
primary key.
`pksiz' specifies the size of the region of the
primary key.
`cbuf' specifies the pointer to the region of the
zero separated column string where the name and the value of each column are
situated one after the other.
`csiz' specifies the size of the region of the
column string.
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.
`tdb' specifies the table database object
connected as a writer.
`pkstr' specifies the string of the primary
key.
`cstr' specifies the string of the the tab
separated column string where the name and the value of each column are
situated one after the other.
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.
`tdb' specifies the table database object
connected as a writer.
`pkbuf' specifies the pointer to the region of the
primary key.
`pksiz' specifies the size of the region of the
primary key.
`cols' specifies a map object containing
columns.
If successful, the return value is true, else, it is
false.
If a record with the same key exists in the database,
this function has no effect.
`tdb' specifies the table database object
connected as a writer.
`pkbuf' specifies the pointer to the region of the
primary key.
`pksiz' specifies the size of the region of the
primary key.
`cbuf' specifies the pointer to the region of the
zero separated column string where the name and the value of each column are
situated one after the other.
`csiz' specifies the size of the region of the
column string.
If successful, the return value is true, else, it is
false.
If a record with the same key exists in the database,
this function has no effect.
`tdb' specifies the table database object
connected as a writer.
`pkstr' specifies the string of the primary
key.
`cstr' specifies the string of the the tab
separated column string where the name and the value of each column are
situated one after the other.
If successful, the return value is true, else, it is
false.
If a record with the same key exists in the database,
this function has no effect.
`tdb' specifies the table database object
connected as a writer.
`pkbuf' specifies the pointer to the region of the
primary key.
`pksiz' specifies the size of the region of the
primary key.
`cols' specifies a map object containing
columns.
If successful, the return value is true, else, it is
false.
If there is no corresponding record, a new record is
created.
`tdb' specifies the table database object
connected as a writer.
`pkbuf' specifies the pointer to the region of the
primary key.
`pksiz' specifies the size of the region of the
primary key.
`cbuf' specifies the pointer to the region of the
zero separated column string where the name and the value of each column are
situated one after the other.
`csiz' specifies the size of the region of the
column string.
If successful, the return value is true, else, it is
false.
If there is no corresponding record, a new record is
created.
`tdb' specifies the table database object
connected as a writer.
`pkstr' specifies the string of the primary
key.
`cstr' specifies the string of the the tab
separated column string where the name and the value of each column are
situated one after the other.
If successful, the return value is true, else, it is
false.
If there is no corresponding record, a new record is
created.
`tdb' specifies the table database object
connected as a writer.
`pkbuf' specifies the pointer to the region of the
primary key.
`pksiz' specifies the size of the region of the
primary key.
If successful, the return value is true, else, it is
false.
`tdb' specifies the table database object
connected as a writer.
`pkstr' specifies the string of the primary
key.
If successful, the return value is true, else, it is
false.
`tdb' specifies the table database object.
`pkbuf' specifies the pointer to the region of the
primary key.
`pksiz' specifies the size of the region of the
primary key.
If successful, the return value is a map object of the
columns of the corresponding record. `NULL' is returned if no record
corresponds.
Because the object of the return value is created with
the function `tcmapnew', it should be deleted with the function `tcmapdel'
when it is no longer in use.
`tdb' specifies the table database object.
`pkbuf' specifies the pointer to the region of the
primary key.
`pksiz' specifies the size of the region of the
primary key.
`sp' specifies the pointer to the variable into
which the size of the region of the return value is assigned.
If successful, the return value is the pointer to the
region of the column string of the corresponding record. `NULL' is returned if
no record corresponds.
Because an additional zero code is appended at the end of
the region of the return value, the return value can be treated as a character
string. Because the region of the return value is allocated with the `malloc'
call, it should be released with the `free' call when it is no longer in
use.
`tdb' specifies the table database object.
`pkstr' specifies the string of the primary
key.
If successful, the return value is the tab separated
column string of the corresponding record. `NULL' is returned if no record
corresponds.
Because the region of the return value is allocated with
the `malloc' call, it should be released with the `free' call when it is no
longer in use.
`tdb' specifies the table database object.
`kbuf' specifies the pointer to the region of the
primary key.
`ksiz' specifies the size of the region of the
primary key.
If successful, the return value is the size of the value
of the corresponding record, else, it is -1.
`tdb' specifies the table database object.
`kstr' specifies the string of the primary
key.
If successful, the return value is the size of the value
of the corresponding record, else, it is -1.
`tdb' specifies the table database object.
If successful, the return value is true, else, it is
false.
The iterator is used in order to access the primary key
of every record stored in a database.
`tdb' specifies the table database object.
`sp' specifies the pointer to the variable into
which the size of the region of the return value is assigned.
If successful, the return value is the pointer to the
region of the next primary key, else, it is `NULL'. `NULL' is returned when no
record is to be get out of the iterator.
Because an additional zero code is appended at the end of
the region of the return value, the return value can be treated as a character
string. Because the region of the return value is allocated with the `malloc'
call, it should be released with the `free' call when it is no longer in use.
It is possible to access every record by iteration of calling this function.
It is allowed to update or remove records whose keys are fetched while the
iteration. However, it is not assured if updating the database is occurred
while the iteration. Besides, the order of this traversal access method is
arbitrary, so it is not assured that the order of storing matches the one of
the traversal access.
`tdb' specifies the table database object.
If successful, the return value is the string of the next
primary key, else, it is `NULL'. `NULL' is returned when no record is to be
get out of the iterator.
Because the region of the return value is allocated with
the `malloc' call, it should be released with the `free' call when it is no
longer in use. It is possible to access every record by iteration of calling
this function. However, it is not assured if updating the database is occurred
while the iteration. Besides, the order of this traversal access method is
arbitrary, so it is not assured that the order of storing matches the one of
the traversal access.
`tdb' specifies the table database object.
If successful, the return value is a map object of the
columns of the next record, else, it is `NULL'. `NULL' is returned when no
record is to be get out of the iterator. The primary key is added into the map
as a column of an empty string key.
Because the object of the return value is created with
the function `tcmapnew', it should be deleted with the function `tcmapdel'
when it is no longer in use. It is possible to access every record by
iteration of calling this function. However, it is not assured if updating the
database is occurred while the iteration. Besides, the order of this traversal
access method is arbitrary, so it is not assured that the order of storing
matches the one of the traversal access.
`tdb' specifies the table database object.
`pbuf' specifies the pointer to the region of the
prefix.
`psiz' specifies the size of the region of the
prefix.
`max' specifies the maximum number of keys to be
fetched. If it is negative, no limit is specified.
The return value is a list object of the corresponding
keys. This function does never fail. It returns an empty list even if no key
corresponds.
Because the object of the return value is created with
the function `tclistnew', it should be deleted with the function `tclistdel'
when it is no longer in use. Note that this function may be very slow because
every key in the database is scanned.
`tdb' specifies the table database object.
`pstr' specifies the string of the prefix.
`max' specifies the maximum number of keys to be
fetched. If it is negative, no limit is specified.
The return value is a list object of the corresponding
keys. This function does never fail. It returns an empty list even if no key
corresponds.
Because the object of the return value is created with
the function `tclistnew', it should be deleted with the function `tclistdel'
when it is no longer in use. Note that this function may be very slow because
every key in the database is scanned.
`tdb' specifies the table database object
connected as a writer.
`kbuf' specifies the pointer to the region of the
primary key.
`ksiz' specifies the size of the region of the
primary key.
`num' specifies the additional value.
If successful, the return value is the summation value,
else, it is `INT_MIN'.
The additional value is stored as a decimal string value
of a column whose name is "_num". If no record corresponds, a new
record with the additional value is stored.
`tdb' specifies the table database object
connected as a writer.
`kbuf' specifies the pointer to the region of the
primary key.
`ksiz' specifies the size of the region of the
primary key.
`num' specifies the additional value.
If successful, the return value is the summation value,
else, it is Not-a-Number.
The additional value is stored as a decimal string value
of a column whose name is "_num". If no record corresponds, a new
record with the additional value is stored.
`tdb' specifies the table database object
connected as a writer.
If successful, the return value is true, else, it is
false.
This function is useful when another process connects to
the same database file.
`tdb' specifies the table database object
connected as a writer.
`bnum' specifies the number of elements of the
bucket array. If it is not more than 0, the default value is specified. The
default value is two times of the number of records.
`apow' specifies the size of record alignment by
power of 2. If it is negative, the current setting is not changed.
`fpow' specifies the maximum number of elements of
the free block pool by power of 2. If it is negative, the current setting is
not changed.
`opts' specifies options by bitwise-or:
`TDBTLARGE' specifies that the size of the database can be larger than 2GB by
using 64-bit bucket array, `TDBTDEFLATE' specifies that each record is
compressed with Deflate encoding, `TDBTBZIP' specifies that each record is
compressed with BZIP2 encoding, `TDBTTCBS' specifies that each record is
compressed with TCBS encoding. If it is `UINT8_MAX', the current setting is
not changed.
If successful, the return value is true, else, it is
false.
This function is useful to reduce the size of the
database file with data fragmentation by successive updating.
`tdb' specifies the table database object
connected as a writer.
If successful, the return value is true, else, it is
false.
`tdb' specifies the table database object.
`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
function is useful to create a backup file of the database file.
`tdb' specifies the table database object
connected as a writer.
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. Because all pages
are cached on memory while the transaction, the amount of referred records is
limited by the memory capacity. If the database is closed during transaction,
the transaction is aborted implicitly.
`tdb' specifies the table database object
connected as a writer.
If successful, the return value is true, else, it is
false.
Update in the transaction is fixed when it is committed
successfully.
`tdb' specifies the table database object
connected as a writer.
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.
`tdb' specifies the table database object.
The return value is the path of the database file or
`NULL' if the object does not connect to any database file.
`tdb' specifies the table database object.
The return value is the number of records or 0 if the
object does not connect to any database file.
`tdb' specifies the table database object.
The return value is the size of the database file or 0 if
the object does not connect to any database file.
`tdb' specifies the table database object
connected as a writer.
`name' specifies the name of a column. If the name
of an existing index is specified, the index is rebuilt. An empty string means
the primary key.
`type' specifies the index type: `TDBITLEXICAL'
for lexical string, `TDBITDECIMAL' for decimal string, `TDBITTOKEN' for token
inverted index, `TDBITQGRAM' for q-gram inverted index. If it is `TDBITOPT',
the index is optimized. If it is `TDBITVOID', the index is removed. If
`TDBITKEEP' is added by bitwise-or and the index exists, this function merely
returns failure.
If successful, the return value is true, else, it is
false.
Note that the setting indices should be set after the
database is opened.
`tdb' specifies the table database object
connected as a writer.
The return value is the new unique ID number or -1 on
failure.
`tdb' specifies the table database object.
The return value is the new query object.
`qry' specifies the query object.
`qry' specifies the query object.
`name' specifies the name of a column. An empty
string means the primary key.
`op' specifies an operation type: `TDBQCSTREQ' for
string which is equal to the expression, `TDBQCSTRINC' for string which is
included in the expression, `TDBQCSTRBW' for string which begins with the
expression, `TDBQCSTREW' for string which ends with the expression,
`TDBQCSTRAND' for string which includes all tokens in the expression,
`TDBQCSTROR' for string which includes at least one token in the expression,
`TDBQCSTROREQ' for string which is equal to at least one token in the
expression, `TDBQCSTRRX' for string which matches regular expressions of the
expression, `TDBQCNUMEQ' for number which is equal to the expression,
`TDBQCNUMGT' for number which is greater than the expression, `TDBQCNUMGE' for
number which is greater than or equal to the expression, `TDBQCNUMLT' for
number which is less than the expression, `TDBQCNUMLE' for number which is
less than or equal to the expression, `TDBQCNUMBT' for number which is between
two tokens of the expression, `TDBQCNUMOREQ' for number which is equal to at
least one token in the expression, `TDBQCFTSPH' for full-text search with the
phrase of the expression, `TDBQCFTSAND' for full-text search with all tokens
in the expression, `TDBQCFTSOR' for full-text search with at least one token
in the expression, `TDBQCFTSEX' for full-text search with the compound
expression. All operations can be flagged by bitwise-or: `TDBQCNEGATE' for
negation, `TDBQCNOIDX' for using no index.
`expr' specifies an operand exression.
`qry' specifies the query object.
`name' specifies the name of a column. An empty
string means the primary key.
`type' specifies the order type: `TDBQOSTRASC' for
string ascending, `TDBQOSTRDESC' for string descending, `TDBQONUMASC' for
number ascending, `TDBQONUMDESC' for number descending.
`qry' specifies the query object.
`max' specifies the maximum number of records of
the result. If it is negative, no limit is specified.
`skip' specifies the number of skipped records of
the result. If it is not more than 0, no record is skipped.
`qry' specifies the query object.
The return value is a list object of the primary keys of
the corresponding records. This function does never fail. It returns an empty
list even if no record corresponds.
Because the object of the return value is created with
the function `tclistnew', it should be deleted with the function `tclistdel'
when it is no longer in use.
`qry' specifies the query object of the database
connected as a writer.
If successful, the return value is true, else, it is
false.
`qry' specifies the query object of the database
connected as a writer.
`proc' specifies the pointer to the iterator
function called for each record. It receives four parameters. The first
parameter is the pointer to the region of the primary key. The second
parameter is the size of the region of the primary key. The third parameter is
a map object containing columns. The fourth parameter is the pointer to the
optional opaque object. It returns flags of the post treatment by bitwise-or:
`TDBQPPUT' to modify the record, `TDBQPOUT' to remove the record, `TDBQPSTOP'
to stop the iteration.
`op' specifies an arbitrary pointer to be given as
a parameter of the iterator function. If it is not needed, `NULL' can be
specified.
If successful, the return value is true, else, it is
false.
`qry' specifies the query object.
The return value is the hint string.
`qrys' specifies an array of the query
objects.
`num' specifies the number of elements of the
array.
`type' specifies a set operation type:
`TDBMSUNION' for the union set, `TDBMSISECT' for the intersection set,
`TDBMSDIFF' for the difference set.
The return value is a list object of the primary keys of
the corresponding records. This function does never fail. It returns an empty
list even if no record corresponds.
If the first query object has the order setting, the
result array is sorted by the order. Because the object of the return value is
created with the function `tclistnew', it should be deleted with the function
`tclistdel' when it is no longer in use.
SEE ALSO¶
tcttest(1), tctmttest(1), tctmgr(1), tokyocabinet(3)2012-08-18 | Man Page |