Database

No, not if you're using Managed API (Data.SQLClient)

If your application uses ADO or OLEDB or ODBC or other API's to access SQL Server

Both refer to the same thing.

Both refer to the same thing. Both this and the question above is 
probably because you can use multiple interchangeable keywords in the SQLConnection ConnectionString property.
Refer to <a href="http://msdn2.microsoft.com/en-us/library/system.data.sqlclient.sqlconnection.connectionstring.aspx">this</a>[<a href="http://msdn2.microsoft.com/en-us/library/system.data.sqlclient.sqlconnection.connectionstring.aspx" target="_blank" title="New Window">^</a>] article for details. 

Depends on what kind of license you've bought for your server. There are per CPU licenses
 and per connection licenses. IIRC you'll get atleast 5 connetions if you opt for the per
 connection license.

Yes. Definitely

Yes again

If you're using a centralized server, you don't have to use the Express Edition. Express
 edition is meant to be a standalone database on every system and is not looked
 at for multiple users. 
Read <a href="http://www.microsoft.com/sql/howtobuy/faq.mspx">this</a>[<a href="http://www.microsoft.com/sql/howtobuy/faq.mspx" target="_blank" title="New Window">^</a>]
and <a href="http://www.microsoft.com/sql/prodinfo/features/compare-features.mspx">this</a>[<a href="http://www.microsoft.com/sql/prodinfo/features/compare-features.mspx" target="_blank" title="New Window">^</a>] for further clarifications.

chithra.r wrote:

without using "COUNT"

select max(rows)<br />
from sysindexes <br />
where indid < 2<br />
and id = object_id('TableName')

select 'Rows in table:'+cast((select count(*) from tablename)as varchar(20))

Select MAX(rowid)-MIN(rowid) from table