b-xiang / LunarBase

LunarBase engine (in C and Java) targets a real-time and free style database engine, managing 2 billions of records in one table, where each record has a size limitation up to 32k bytes, and it can be used as a search engine as well. Seek more in the [Wiki](https://github.com/LunarBaseEngin/LunarBase/wiki) .

#10 minuts getting started

Current Lunarbase runs on Linux + X86 platform:

1. X86 platform;
2. 4GB memory;
3. 2 cores of CPU;
4. 64-bit Linux;
5. JVM 1.8 or later;
6. GCC 4.8.4 or later;

You may check out here and benchmark to verify your working enviroment.

Runnable examples are under the folder example, clone this project to your desktop, and run it for yourself.

creation.conf is the configure file that tells LunarBase how to initialize a database. Any parameters in the creation example can be changed to meet your requirements. For example, if you need to cache the hottest 1 million records in memory, you shall change the parameter cache_records_in_memory = 20, (1 << 20 = 1 million). Of course, all the runtime tunable parameters can be changed at any time the db running.

#step 1: create a new database

 String creation_conf = "/home/feiben/EclipseWorkspace/LunarBaseTutorial/creation.conf";  
 LunarDB.getInstance().createDB(creation_conf);  
 LunarDB.getInstance().closeDB();  

Where within the creation.conf, it tells us the database locates under root_path=/home/feiben/DBTest/, and the name is RTSeventhDB.

# ----------------#  
# Global settings #  
# --------------- #  

root_path=/home/feiben/DBTest/  

database_name = RTSeventhDB  

So the db root is /home/feiben/DBTest/RTSeventhDB. The DBTaskCenter knowns from where to create the engine instance:

#step 2: create a new table and insert data to it

String db_root = "/home/feiben/DBTest/RTSeventhDB";  
DBTaskCenter tc = new DBTaskCenter(db_root);  
String table = "order";
if(!tc.getActiveDB().hasTable(table))
{
    tc.getActiveDB().createTable(table); 
    tc.getActiveDB().openTable(table);  
}
		
LunarTable l_table = tc.getActiveDB().getTable(table);
l_table.addSearchable("string", "name");
l_table.addSearchable("int", "payment");
l_table.addSearchable("int", "age");
		
			
/*  
 * Step 1: construct an object of a records array  
 */  
 String[] records = new String[6];  
 records[0] = "{name=jackson8, payment=500, age=36}";  
 records[1] = "{name=jackson9, payment=500, age=25}";  
 records[2] = "{name=John8, payment=600, age=36}";  
 records[3] = "{name=Rafael8, payment=600, age=36}";  
 records[4] = "{name=Rafael9, payment=700, age=25}";  
 records[5] = "{name=John9, payment=700, age=36}";  
 		
 /*  
  * Step2: dispatch it. LunarBase engine handles it.  
  */  
 LFuture<Record32KBytes[]> inserted = tc.dispatch(new IncommingRecords(table, records));  
 tc.saveDB();  

#step 3: simple query

 /*  
  * Step 3: Test query, see if they are correctly inserted,   
  * and if property-value pair can be retrieved.   
  */  
 QuerySimple sq = new QuerySimple(table, "age", "36", 200);  
 tc.dispatch(sq);

#step 4: shut down the database

 /*  
  * Step 4: Must not forget to shut down the db.  
  */  
 tc.shutdownDB();

Embeded version

For elaboration on the features and use of LunarBase, please visit the wiki here

or download the knowledge base file at here