What factors can affect the performance of a database?

Question

I need this question answered for a school discussion board.

Answer 1

Indexes

Normalization

Variable vs fixed size character fields

Number of joins

Clustering

Fragmenting

Striping

Answer 2

Well, you could have I/O contention on the disks.   There could be other processes on the server, vying for the CPU.

You can also check the setup of the database:  is it properly indexed?  Is it over-indexed?   Are regularly-used results cached?   Are SQL statements reused or does the database have to re-parse everything it sees?

You also need to check out the application.  Many times, this is where you will find the problems.  Poorly-written SQL.  Bad table design.  Too many trips to the database.  This list is endless.  Developers hate it when you target the application.

One last factor could be the network.  If you have latency between the application server, the database server or even the individual users, you could see what appear to be performance issues.

Answer 3

how long it takes you to access the server, for example, how many hops there are to get to the server, get it? well there's that and the performance of the server itself, if it has a 300RPM HDD (ancient) compared to a 10,000 Raptor HDD RAID 0, then the second one would outperform the first by alot...