sdb is a simple string key/value database based on djb's cdb disk storage and supports JSON and arrays introspection.
mcsdbd is a memcache server with disk storage based on sdb. It is distributed as a standalone binary and a library.
There's also the sdbtypes: a vala library that implements several data structures on top of an sdb or a memcache instance.
pancake pancake@nopcode.org
- namespaces (multiple sdb paths)
- atomic database sync (never corrupted)
- bindings for vala, luvit, newlisp and nodejs
- commandline frontend for sdb databases
- memcache client and server with sdb backend
- arrays support (syntax sugar)
- json parser/getter (js0n.c)
- disk storage based on cdb code
- memory hashtable based on wayland code
- linked lists from r2 api
I have modified cdb code a little to create smaller databases and be memory leak free in order to use it from a library.
The sdb's cdb database format is 10% smaller than the original one. This is because keylen and valuelen are encoded in 4 bytes: 1 for the key length and 3 for the value length.
In a test case, a 4.3MB cdb database takes only 3.9MB after this file format change.
Let's create a database!
$ sdb d hello=world
$ sdb d hello
world
Using arrays (>=0.6):
$ sdb - '()list=1,2' '(0)list' '(0)list=foo' '()list' '(+1)list=bar'
1
foo
2
foo
fuck
2
Let's play with json:
$ sdb d g='{"foo":1,"bar":{"cow":3}}'
$ sdb d g?bar.cow
3
$ sdb - user='{"id":123}' user?id=99 user?id
99
Using the commandline without any disk database:
$ sdb - foo=bar foo a=3 +a -a
bar
4
3
$ sdb -
foo=bar
foo
bar
a=3
+a
4
-a
3
Remove the database
$ rm -f d
To make a backup of a database to move it between different boxes use the textual format:
$ sdb my.db | xz > my.xz
$ du -hs my.*
my.db 3.9M
my.xz 5K
Using ascii+xz is the best option for storing compressed sdb databases:
$ gzip < my.db | wc -c
110768
$ xz -9 < my.db | wc -c
37480
$ sdb my.db | xz -9 | wc -c
5620
$ sdb my.db | lzma -9 | wc -c
5575
To import the database:
$ xz -d < my.xz | sdb my.db =