This module aims to provide simple DML to manipulate the hashes in REDIS for SQL users. It works as simple as you expected. It translates the input statement to a set of pure REDIS commands. It does not need nor generate any intermediate stuffs which occupied your storages. The target data is your hashes only.

Usage

$ redis-cli
127.0.0.1:6379> hmset phonebook:0001 name "Peter Nelson"     tel "1-456-1246-3421" birth "2019-10-01" pos 3 gender "M"
127.0.0.1:6379> hmset phonebook:0002 name "Betty Joan"       tel "1-444-9999-1112" birth "2019-12-01" pos 1 gender "F"
127.0.0.1:6379> hmset phonebook:0003 name "Bloody Mary"      tel "1-666-1234-9812" birth "2018-01-31" pos 2 gender "F"
127.0.0.1:6379> hmset phonebook:0004 name "Mattias Swensson" tel "1-888-3333-1412" birth "2017-06-30" pos 4 gender "M"
127.0.0.1:6379> dbx.select name,tel from phonebook where gender = "F" order by pos desc
1) 1) name
   2) "Bloody Mary"
   3) tel
   4) "1-666-1234-9812"
2) 1) name
   2) "Betty Joan"
   3) tel
   4) "1-444-9999-1112"

Getting started

Get the package and build the binary:

$ git clone https://github.com/cscan/dbx.git
$ cd dbx/src && make

This plugin library is written in pure C. A file dbx.so is built after successfully compiled.

Load the module in redis (3 ways)

Load the module in CLI

127.0.0.1:6379> module load /path/to/dbx.so

Start the server with loadmodule argument

$ redis-server --loadmodule /path/to/dbx.so

Adding the following line in the file redis.conf and then restart the server

loadmodule /path/to/dbx.so

If you still have problem in loading the module, please visit: https://redis.io/topics/modules-intro

More Example

Select Statement

You may specify multiple fields separated by comma

127.0.0.1:6379> dbx.select name, gender, birth from phonebook
1) 1) name
   2) "Betty Joan"
   3) gender
   4) "F"
   5) birth
   6) "2019-12-01"
2) 1) name
   2) "Mattias Swensson"
   3) gender
   4) "M"
   5) birth
   6) "2017-06-30"
3) 1) name
   2) "Peter Nelson"
   3) gender
   4) "M"
   5) birth
   6) "2019-10-01"
4) 1) name
   2) "Bloody Mary"
   3) gender
   4) "F"
   5) birth
   6) "2018-01-31"

"*" is support

127.0.0.1:6379> dbx.select * from phonebook where birth > '2019-11-11'
1)  1) "name"
    2) "Betty Joan"
    3) "tel"
    4) "1-444-9999-1112"
    5) "birth"
    6) "2019-12-01"
    7) "pos"
    8) "1"
    9) "gender"
   10) "F"

If you want to show the exact keys, you may try rowid()

127.0.0.1:6379> dbx.select rowid() from phonebook
1) 1) rowid()
   2) "phonebook:1588299191-764848276"
2) 1) rowid()
   2) "phonebook:1588299202-1052597574"
3) 1) rowid()
   2) "phonebook:1588298418-551514504"
4) 1) rowid()
   2) "phonebook:1588299196-2115347437"

The above is nearly like REDIS keys command

127.0.0.1:6379> keys phonebook*
1) "phonebook:1588298418-551514504"
2) "phonebook:1588299196-2115347437"
3) "phonebook:1588299202-1052597574"
4) "phonebook:1588299191-764848276"

Each record is exactly a hash, you could use raw REDIS commands hget, hmget or hgetall to retrieve the same content

Where in Select Statement

This module supports =, >, <, >=, <=, <>, != and like conditions. Only single condition is allowed.

127.0.0.1:6379> dbx.select tel from phonebook where name like Son
1) 1) tel
   2) "1-888-3333-1412"
2) 1) tel
   2) "1-456-1246-3421"

Order in Select Statement

Ordering can be ascending or descending. All sortings are alpha-sort.

127.0.0.1:6379> dbx.select * from phonebook order by pos asc
...
127.0.0.1:6379> dbx.select * from phonebook order by pos desc
...

Delete Statement

You may also use Insert and Delete statement to operate the hash

127.0.0.1:6379> dbx.delete from phonebook where gender = F
(integer) 2
127.0.0.1:6379> dbx.delete from phonebook
(integer) 2

Insert Statement

127.0.0.1:6379> dbx.insert into phonebook (name,tel,birth,pos,gender) values ('Peter Nelson'     ,1-456-1246-3421, 2019-10-01, 3, M)
"phonebook:1588298418-551514504"
127.0.0.1:6379> dbx.insert into phonebook (name,tel,birth,pos,gender) values ('Betty Joan'       ,1-444-9999-1112, 2019-12-01, 1, F)
"phonebook:1588299191-764848276"
127.0.0.1:6379> dbx.insert into phonebook (name,tel,birth,pos,gender) values ('Bloody Mary'      ,1-666-1234-9812, 2018-01-31, 2, F)
"phonebook:1588299196-2115347437"
127.0.0.1:6379> dbx.insert into phonebook (name,tel,birth,pos,gender) values ('Mattias Swensson' ,1-888-3333-1412, 2017-06-30, 4, M)
"phonebook:1588299202-1052597574"

Please be noted that Redis requires at least one space after the single and double quoted arguments. Or you may quote the whole SQL statement as below:

127.0.0.1:6379> dbx.insert "into phonebook (name,tel,birth,pos,gender) values ('Peter Nelson','1-456-1246-3421','2019-10-01',3, 'M')"

Issue command from BASH shell

$ redis-cli dbx.select "*" from phonebook where gender = M order by pos desc
1)  1) "name"
    2) "Mattias Swensson"
    3) "tel"
    4) "1-888-3333-1412"
    5) "birth"
    6) "2017-06-30"
    7) "pos"
    8) "4"
    9) "gender"
   10) "M"
2)  1) "name"
    2) "Peter Nelson"
    3) "tel"
    4) "1-456-1246-3421"
    5) "birth"
    6) "2019-10-01"
    7) "pos"
    8) "3"
    9) "gender"
   10) "M"
$ redis-cli dbx.select name from phonebook where tel like 9812
1) 1) name
   2) "Bloody Mary"

Note that "*" requires double quoted otherwise it will pass all the filename in current directory. Of course you could quote the whole SQL statement.

$ redis-cli dbx.select "* from phonebook where gender = M order by pos desc"

Compatibility

REDIS v4.0

License

MIT

Status

Now the Select statement only supports single where condition and single order sequence. I will add more useful features in the future. Simple Insert, Update and Delete statement will be included finally. This project is in an early stage of development. Any contribution is welcome :D