After mysql server restarts I cannot see my own database By mistake I restarted MySQL server in Linux system. But MySQL server was unable to start.

I renamed my.cnf to my_bak.cnf. After that MySQL server started. But I can not see my project database.

I tried below command:

mysql&gt; show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| test               |
+--------------------+
3 rows in set (0.00 sec)


But I can not see prj_db. But the prj_db folder is available in my Linux system.
I want to restore the database from prj_db.

The steps that I have done :


I made a change in max_allowed_packet=500M.
MySQL server is not starting after changing the max_allowed_packet.
I reverted back to my old my.cnf.
After that also server was not started.
Then I renamed the my.cnf to my_bak.cnf.Then server started.But i can not able to see my prj_db database.(Here i thought a new my.cnf will be created.But i can not see any my.cnf file under /etc folder.)
I moved my_bak.cnf file from /etc folder to another location. mysql service started, but I can not see any my.cnf file under /etc folder as well as my prj_db database also.
Please suggest me  how can i reload my prj_db database.


AND I HAVE .MYD,.frm,.MYI Files in my prj_db folder.

----------------------------------my.cnf----------------------- 

[client]
port = 3306
socket = /DB/mysql/mysql.sock

#This is to handle unicode
default-character-set=utf8

[mysqld]
datadir=/DB/mysql
socket=/DB/mysql/mysql.sock
port = 3306
#datadir=/var/lib/mysql
#socket=/var/lib/mysql/mysql.sock

#skip-networking
#skip-external-locking

#
# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
bind-address            = localhost

#Added by JV to store and retrive unicode (native language) data
init_connect='SET collation_connection = utf8_general_ci'
init_connect='SET NAMES utf8'
#character_set_client=utf8
character-set-server=utf8
collation-server=utf8_general_ci
skip-character-set-client-handshake

User=mysql
max_allowed_packet=500M
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0

[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid


But after that I reverted back to old my.cnf and then I moved the .cnf file from /etc folder to other backup place.
Make the sure the datadir in new cnf file is the same as the old one then restart the service and try again.