Delete Duplicate records

The scenario is:

The table has 3 columns, A, B, and C. Column A is unique for all rows
but the columns B and C can be duplicate across rows.
And it needs to remove the rows where B and C are duplicated.

DELETE FROM tbl_name
WHERE a NOT IN
( 
 SELECT MIN(a)
  FROM daTable
  GROUP BY b,c
) 

Website Shifting (All files & DataBase)

Here is the method for Shifting your website & database from one server to another with simple steps. This works only on Linux server.

Steps to follow on Existing(Source) Server:
1. Move in the root folder of project i.e. change the directory
cd /path/to/dir

2. Compress the website(project) folder
tar -cvf xxxx.tar * (Supposing 'xxxx' is the name of project)

3. Export the Database in a tar file
mysqldump dbName -u dbUserName -p > dbFileName.tar
Password: myPassword

example:
mysqldump xxxx -u root -p > xxxx_DB_Backup.tar
Password: password

4. Copy the tar files to New server, where you want to shift (move) the website
scp xxxx.tar RemoteUserName@RemoteIP:/path/to/dir/xxxx.tar
Password: (password for that user of Remote IP)

example:
scp xxxx.tar root@127.0.0.1:/home/xyz/public_html/xxxx.tar
Password: myRootPassword

scp xxxx_DB_Backup.tar root@127.0.0.1:/home/xyz/public_html/xxxx_DB_Backup.tar
Password: myRootPassword

Steps to follow onNew(Target) Server:
1. Move in the root folder of project, where you have copied the compressed file
cd /path/to/dir

2. UnTar the tar file
tar -xvf xxxx.tar

3. Import the Database
mysql myDbName -u dbUserName -p < dbFileName.tar
Password: myPassword

Full Backup of MySQL DataBase

Here are some methods for FULL backup of MySQL Databases. This way all the constraints, stored procedures, triggers etc will be copied for backup and/or replicating the database.

Depending on your access to server, you can choose the different options.
e.g. you will not be able to copy the files from a shared hosting server (Method 3)

METHOD 1:
shell> mysqldump --tab=/path/to/some/dir --opt --full

METHOD 2:
shell> mysqlhotcopy database /path/to/some/dir

METHOD 3:
    simply copy all table files (`*.frm', `*.MYD', and `*.MYI' files)

METHOD 4:
    You can write your own script which you can use to backup your database with various options. An example script can be downloaded from here

Please comment to this post to suggest more methods which can be added here.
Thanks

SQL Server 2000 Vs MYSQL v4.1 ( Limits)

Here you can find comparison of Limits.. between 'SQL Server 2000' & 'MySQL 4.1'

Feature	SQL Server 2000	MySQL 4.1
column name length	128	64
index name length	128	64
table name length	128	64
max indexes per table	250	32
index length	900	1024
max index column length	900	255
columns per index	16	16
max char() size	8000	1048543
max varchar() size	8000	1048543
max blob size	2147483647	1048543
max number of columns in GROUP BY	Limited only by number of bytes (8060)	64
max number of columns in ORDER BY	Limited only by number of bytes (8060)	64
tables per SELECT statement	256	31
max columns per table	1024	2599
max table row length	8036	65534
longest SQL statement	16777216	1048574
constant string size in SELECT	16777207	1048565