add concept

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uleelx 2015-04-06 23:55:11 +08:00
parent ec225bb6d7
commit 544ae720a5

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@ -10,8 +10,20 @@ When To Use FlatDB
When you want to use SQLite to store data, just take a glance at FlatDB.<br>
When Lua acts in your program as the major language or the embedded scripting language, just try using FlatDB.
Concept
==========
| FlatDB | Disk | Lua |
|:--------------:|:-------------:|:--------------:|
| Database | Directory | Table |
| Book | File | Table |
| Key-value pair | File content | Key-value pair |
Keys and values can be all Lua types except coroutines, userdata, cdata and C functions.
Usage
==========
Copy *flatdb.lua* file to your project or where your lua libraries stored.<br>
Then write this in any Lua file where you want to use it:
```lua
@ -60,10 +72,12 @@ Quick Look
```lua
local flatdb = require("flatdb")
-- open a directory as a database, 'db' is just a plain empty Lua table that can contain books
-- open a directory as a database
-- 'db' is just a plain empty Lua table that can contain books
local db = flatdb("./db")
-- open or create a book named "default", it also a plain empty Lua table where key-value data stored in
-- open or create a book named "default"
-- it is also a plain empty Lua table where key-value pair stored in
if not db.default then
db.default = {}
end
@ -97,11 +111,11 @@ db:guard(function(book, key, value)
print("CREATE KEY permission denied!")
end)
-- try creating new key-value data to 'default' book
-- try creating new key-value pair to 'default' book
db:set("key1", 1)
db:set("key2", 2)
-- update an existing key-value item
-- update an existing key-value pair
db:set("hello", "bye")
print(db:get("key1")) -- prints nil