Hi i'm creating a FORUM i'm using asp.internet, c# language for code. I've read a article about NoSql i inspired so much from there edge on RDBMS (sql) so i believed which should i personally use NoSql concept for Forum DataBase or otherwise. I'm not a expert in database. So can u suggest me must i use NoSql? Presently I'm using sql(rdbms).

Is dependent on which you wanna use your forum.

If you wish to store and retrieve user-written messages, then SQL is going to do fine. If you wish to evaluate user associations (Graph problem), you will need to examine Neo4J. If you wish to store lots of large documents, but this is not on the file system, you will need to use NoSQL.

If you wish to have the ability to alter the table structure 100 occasions throughout, NoSQL is what you want. Else, stick to SQL.

Since a forum is remotely associated with what twitter does, I'd look what twitter uses.