SQlServer 2000 and 2005 and 2008 differences

1. In SQL Server 2000 the Query Analyzer and Enterprise Manager are seperate,whereas in SQL Server 2005 both were combined as Management Studio.

2. In Sql 2005,the new datatype XML is used,whereas in Sql 2000 there is no such datatype

3. In Sql server2000 we can create 65,535 databases,whereas in Sql server2005 2(pow(20))-1 databases can be created.

4. In sql server 2005,There is no option to compress backup files, but in sql server 2008,there you find it.

Some good differences

Generally TOP clause is used to perform SELECT on top n results. This feature of TOP is extended in SQL 2005 so that we can also use expression apart from int, bigint and percent to perform query and also extended to be used in UPDATE and DELETE statements.

In SQL 2000

syntax: select Top N [Percent]

EX:
select Top 10 * from TableName

or
select Top 10 Percent * from TableName

Note:

N specifies how many rows are returned. If PERCENT is not specified, n is the number of rows to return. If PERCENT is specified, n is the percentage of the result set rows to return

storing backup file takes 5 minutes without compression in sqlserver 2005,but it takes only 3 minutes in sql server 2008 for storing backup files with compression.

cpu is used to compress the data before it is written to disk,so less data is written to disk.

There are many new features, so it depends on what you need. If you store large files in SQL Server, migrated from Oracle and want to use date and time data types, need to encrypt your databases, etc you will definitely want to look at 2008. The nice thing is that it upgrading should be much easier from 2005 to 2008 than it was from 2000 to 2005

http://blogs.msdn.com/dsimmons/pages/entity-framework-faq.aspx