The writing of the page from memory to disk.

All writes happen in memory, then internal processes within SQL take the written to pages from memory and push them to disk.

Logical is anything to do with memory, so a logical write is writing to the page in memory.

No they are two completly different indexes, one will work if you only ever search on the ID but want to show CH, NA in the result set the other...

But you wanted to list logins which dont have a role assigned to them, which is why they are null.

This query does not list logins which are not assigned any...

http://www.simple-talk.com/sql/database-administration/gail-shaws-sql-server-howlers/, read the poor index design section for index key column order

All down to the order the columns are defined in the index, vs how you reference them in the SQL statement

You wont want the is_disabled flag in the join criteria, you would want it in the select, so that you can see if the login is disabled or not

SELECT

ISNULL(DP.Name, SP.Name)...

What is the question?

Because SUM returns an INT value, you need to cast the whole SUM command back to VARCHAR, not just the cfh.value/100

The error is converting Varchar to Numeric, so the only conversion of that type happening which is explicit is

CONVERT(NUMERIC(20,2), ABS(CFH.VALUE)/100) ELSE 0 END)

So you either have values in CFH.value which...

Execute as caller wont work, you will need to elevate the permissions to an account which has access unless you want to grant the caller the access they need to...

=FORMAT(Field!DateField.Value "MMMM yy")

How about the above?

You will need to grant the server role securityadmin, which will allow the user to create logins at the server level and then create users in the database level based...

use the is_disabled flag on sys.server_principles and then join back to this as well for any missing logins which dont have a user in the DB

Unless you had custom auditing there is no way to 100% say yes you can find out what happened.

You could try the default trace but depending how busy your sever...