I have a database named mydb that has 3 tables:

table1 = 1,400,000 rows
table2 = 4,000 rows
table3 = 100,000 rows

and ever since I tried to add an indexing to table3, it's not responding.

I can't open any of the 3 tables in phpmyadmin (it keeps loading forever, but I can successfully load the database page with the list of tables though) and I can't access the tables via 'mysql' command from SSH (but I can log in though). When I perform 'use mydb' (without -A switch for mysql in command line), it seems to be loading the database structure (table information) forever; with the -A switch for mysql, 'use mydb' works but not 'SELECT * FROM table3 LIMIT 1' nor whatsoever - it's loading forever and not responding at all.

My initial guess is that the indexing is still going on as the table has like 100,000 rows. Can that be the reason? But it's been like 24 hours.

I'm so horrified that I may have broken the database? How can I get it to respond or how can I get a backup of it so that I can create a grand new database from this one?

Thanks and in need of help very much!

It looks lilke your db is stuck in a bad state.
Even creating an index on a multi million rows table should be done in a matter of minutes, not hours...

If you can access your server via ssh, I deduct that it's either an vps, or a private server.
In that case, I'd suggest you to try to restart the mysql service.
To do that, you need to become the admin on the server.
It can be done via the command "su" or "sudo".

su is the privilage escalation program to the super user. You have to be both allowed to use it, and to provide the super user (root) password.
It's usage is

su -
< enter root password >
/etc/init.d/mysql restart

sudo is a program that allows you to launch a process as the root, without escalating all your session to the root account.
You still need to be authorized to use the program, but this time, it's your personal account password that will be asked:

sudo /etc/init.d/mysql restart
< enter your user password >

If you have error messages sent back by the db, I'd suggest you to do a table repair.
Here is the documentation about it:
http://dev.mysql.com/doc/refman/5.0/...air-table.html