colddb/README.md

ColdDB
===========

ColdDB is a minetest mod that implements a serverless, asynchronous, NoSQL database engine.<br>
It provides a key or key-value based storage system using plain Lua tables.<br>

Usage
===========

Copy both *colddb.lua* and *async* files to your minetest mod or game. Copy the code from colddb's init file to your mods init file<br>
Write this code in your lua file.
1. create a directory and link it as a database.
```lua
coldbase = colddb.Colddb("mydb")
```
2. store key item(this key has no value)
```lua
coldbase.set_key("MyKey")
```
3. store key-value item
```lua
coldbase.set("MyKeyAndValue", "Hello world")
```
4. retrieve items (get_key's callback(arg) will return true, false, or nil)
```lua
coldbase.get("MyKeyAndValue", nil, function(arg)
	if arg then
		minetest.log(string.format("value:%s", arg))
	end
end)
coldbase.get_key("MyKey", nil, function(arg)
	if arg then
		minetest.log("Found key")
	else
		minetest.log("Key not found")
	end
end)
```
5. delete key(file) this function works on both keys and key-value keys.
```lua
coldbase.remove("MyKeyAndValue")
```
6. if add_to_mem_pool is true(true by default). keys are stored in a weak lua table(memory) it will be removed by the gc if its not in-use. Storing data in memory is to prevent the database from constantly loading up data from files.
```lua
coldbase.add_to_mem_pool = true
```

License
===========

ColdDB is distributed under the LGPLv2.1+ license.