How to fix You don't have permission to access /phpmyadmin/ on this server Wamp

You don't have permission to access /phpmyadmin/ on this server (WAMP)
This is the message I got when I tried to access phpmyadmin after reinstalling WAMP server to a newer version. After some searching I was able to find the problem.

Reason:

When you uninstall your previous WAMP server there will be still few files that will be left not deleted and will not be replaced by the new install. One such file is the phpmyadmin.conf file that is under C:\wamp\alias folder. This file holds the actual path to the phpmyadmin folder inside WAMP.
If the new WAMP server has a new phpmyadmin version this phpmyadmin.conf will still point to the old folder which is not existing inside WAMP.

Solution:

goto C:\wamp\alias\ and edit the phpmyadmin.conf file using notepad

Alias /phpmyadmin "c:/wamp/apps/phpmyadmin2.11.6/"

# to give access to phpmyadmin from outside
# replace the lines
#
#        Order Deny,Allow
# Deny from all
# Allow from 127.0.0.1
#
# by
#
#        Order Allow,Deny
#   Allow from all
#

<Directory "c:/wamp/apps/phpmyadmin2.11.6/">
  Options Indexes FollowSymLinks MultiViews
  AllowOverride all
      Order Deny,Allow
Deny from all
Allow from 127.0.0.1
</Directory>

I just edited the c:/wamp/apps/phpmyadmin2.11.6/ with c:/wamp/apps/phpmyadmin3.1.3.1/
To find your new phpmyadmin folder goto C:\wamp\apps\

Alias /phpmyadmin "c:/wamp/apps/phpmyadmin3.1.3.1/"

# to give access to phpmyadmin from outside
# replace the lines
#
#        Order Deny,Allow
# Deny from all
# Allow from 127.0.0.1
#
# by
#
#        Order Allow,Deny
#   Allow from all
#

<Directory "c:/wamp/apps/phpmyadmin3.1.3.1/">
  Options Indexes FollowSymLinks MultiViews
  AllowOverride all
      Order Deny,Allow
Deny from all
Allow from 127.0.0.1
</Directory>

Now restart the WAMP server and try to access phpmyadmin

phpMyAdmin mysql table overhead

If you are using phpmyadmin to manage mysql databases and tables you have probably seen a red figure for overhead in the space usage section in a table's detailed view.

This is a usual thing when you have lot of deletes and updates in your table fields. Think overhead as empty space and mysql want it to be defragmented. You can simply use the Optimize table link to get rid of the overhead.

How to create foreign key in mysql (InnoDB)

Yes you can definitely create foreign key constraints on mysql. but it can only be enforced in InnoDB storage engine. The default storage engine is MyISAM, you cannot create foreign key constraints in MyISAM. So make sure you create your tables using InnoDB storage engine.
If you are using a phpMyAdmin to work with mysql, look at the following ScreenShot.



Remember, before making a column available for referencing you should make sure that child column has a Index.





Now using Relation view link you can easily create foreign key constraints