Check to see if there is any other activity on Sunday, for example, are there backups going on at the same time?

Based on time you've identified - attempt to track down the main symptoms - which appear to be high CPU. use this information to find other pottential root causes, ...

As mentioned - there are plenty of different layers , possible reasons - I/O subsystem problems,I/O subsystem misconfiguration,Fragmentation,Excessive I/O requested by SQL Server,Inefficient placement of data files on disk

From SQL...

As an immediate workaround you could increase the timeout .

But investigate the underlying reason why the tomeout occurs - for example are there resource issues which causes the query...

As well as all suggestions made above, commit some daily checks on SQL Server Error logs - and check if anything unusual appears woth investigating.

Here is a post for a definition of query tuning - What is SQL Server Tuning? but in reality query tuning and database tuning in general requires solid knowledge across...

When I see Sort warnings - I check a) Statistics are up to date b) Consider Query Tuning

Are you receiving any Sort warnings? these can be a clue of ORDER BY spilling into TempDB and insufficient memory. Check Statistics are up to date

Common causes include insufficient memory, large temporary tables,large queries silling into TempDB. use queries on Monitor TempDB usage or if you want to list...

SQL is the the programming language used to manage relational database systems. Regardless of the datbase server system - there is normally a DML and DDL aspects to the...

@jeff - "short cuts" , in this context means : a) Increasing time pressure on the Production DBA with limited time to plan and apply principles adequately. b)...

Good article. The DBA job is significantly easier in the long run , if discipline and sound priniples are applied.

Many DBAs are pragmatic - i.e they work in a...

Troubleshooting these situations can be tricky, particuarly if processes are running based on business need - without the proper capacity planning exercise.

1) What does the daily upload include, can this...

The first step is to restore the Differential Base i.e the initial full backup with no recovery, then continue with the Differential.

To identify the relevant files via LSN numbers use...

One method to use is to study the Execution Plans of the queries .Analyse the code - for example, is it forcing a table scan - where that may not...