DB(1) FreeBSD General Commands Manual DB(1)
NAME
db - manipulate db(3)'s btree(3) and hash(3) databases
SYNOPSIS
db [-DKiNqV] [-E endian] [-f infile] [-O outsep] [-S visitem]
[-T visspec] [-U unvisitem] [-X extravis] type dbfile [key [...]]
db -d [-iNq] [-E endian] [-f infile] [-T visspec] [-U unvisitem] type
dbfile [key [...]]
db -w [-CDiNqR] [-E endian] [-F insep] [-f infile] [-m mode]
[-P pagesize] [-T visspec] [-U unvisitem] type dbfile
[key value [...]]
DESCRIPTION
db allows manipulation of btree(3) and hash(3) (db(3)) databases.
db has three modes of operation to perform upon dbfile:
read Displays the given keys, and keys described in infile. If
no keys and no infile is specified, the entire database is
displayed. This is the default mode of operation.
delete Enabled with -d. Deletes the given keys, and keys
described in infile.
write Enabled with -w. Writes the given keys and values, and
keys and values described in infile (in the latter case,
entries are separated by insep).
There are two mandatory arguments: type is the database type; either
`btree' or `hash', and dbfile is the database file to manipulate.
Options valid for all modes are:
-E endian Set the endianness of the database. endian may be one
of:
B Big endian
H Host endian
L Little endian
Defaults to `H' (host endian).
-f infile Contains a list of keys (for read and delete), or insep
separated keys and values (for write) to be used as
arguments to the given mode. If infile is `-', stdin
is used.
-i Keys are converted to lower case before manipulation.
-N Include the NUL byte at the end of the key or value.
By convention, each key and value in the underlying
database is terminated with a NUL byte, although it is
possible to have keys or values that are not so
terminated. Without the -N option, db adds a NUL
terminator to any keys and values specified on the
command line or in the input file, before searching or
modifying the underlying database, and removes the last
byte (which is usually a NUL terminator) before
printing any keys and values retrieved from the
underlying database. With the -N option, db does not
add or remove a terminating byte. The -S, -T, and -U
options may be useful to encode the NUL terminator in a
readable form.
-q Quiet operation. In read mode, missing keys are
considered to be an error. In delete (-d) and write
(-w) modes, the result of various operations is
suppressed.
-T visspec Control how the items specified by the -S option are
encoded and -U option are decoded. The visspec option-
argument is a string specifying strsvisx(3) flags. The
string consists of one or more characters:
b VIS_NOSLASH
c VIS_CSTYLE. Overrides h and o.
h VIS_HTTPSTYLE. Overrides c and o.
o VIS_OCTAL. Overrides c and h.
s VIS_SAFE
t VIS_TAB
w VIS_WHITE
-U only supports -T h.
See vis(1)'s corresponding options for the meaning of
these characters, and strsvisx(3) for more detail on
the flags.
-U unvisitem
Specify items to strunvisx(3) decode. The unvisitem
option-argument is a character specifying if the key
(k), the value (v) or both (b) should be decoded.
Read mode specific options are:
-D Display duplicate entries in btree databases.
-K Display key.
-O outsep Field separator string between key and value. Defaults
to a single tab (`\t').
-S visitem Specify items to strsvisx(3) encode. The visitem
option-argument is a character specifying if the key
(k), the value (v) or both (b) should be encoded.
-V Display value.
-X extravis
When encoding items with -S option also encode
characters in extravis, per strsvisx(3).
(If neither of -K or -V is given, both options are enabled.)
Write mode specific options are:
-C Create new database, and truncate existing databases.
-D Allow duplicate entries in btree databases. (Requires
-R to be useful.)
-F insep Input field separator string between key and value used
when parsing infile. Defaults to a single space (` ').
-m mode Octal mode of created database. Defaults to `0644'.
-P pagesize
Set the page size of the table to pagesize bytes. If
set to `0', a database-specific default is determined,
based on the block-size of the underlying file-system.
Defaults to `4096'.
-R Overwrite existing entries. If not specified, writing
to an existing entry raises an error.
SEE ALSO
vis(1), btree(3), db(3), hash(3), strsvisx(3), strunvisx(3)
HISTORY
The db command appeared in NetBSD 2.0.
AUTHORS
Luke Mewburn <
[email protected]>.
FreeBSD 14.1-RELEASE-p8 February 17, 2012 FreeBSD 14.1-RELEASE-p8