I just have a basic SQL problem that i can't seem to solve.
For my company i am trying to create a database that keeps track of users the computer they are useing and the monitor of that computer.

that's been done and is o.k but here is the problem the relationship between the computer table and the monitor table is a 1-N relationship one computer can be assosiated with many monitors the foreign key or rather the link between the two table is the monitor.

i need to be able to add multiple monitors of the same type e.g we buy viewsonic so in theory if i query the monitors table all the monitor type would come back "viewsonic"

in my current setup once i add one monitor of type "viewsonic" to the computer table i cannot add for the second type the same name. how can i make it so i can add multiples of the same type?

You need to add third table (ok, that's one of the option, but it first the situation good). Rename current 'monitor' to 'monitor model'. The new one will be called 'monitor' and has a rather simple structure: key (primary, unique), monitor serial (or any other id that identifies *one* monitor) and foreign key - monitor type.

So, computer table will have 'monitor id' foreign key - key from new 'monitor table'.

Let me see if i understand you:

table: Computer
cpu
monitor_id(pk)

monitor
monitor_id(fk)
serial_number(pk)
monitor_type(pk)

monitor model
monitor_type(fk)
manufacturer
purchase_date


is this correct? are you sure about the associations?

No, that doesn't look right. I don't really understand exactly what you are going for but this may be it.

table: User
user_id (pk)
... other info

table: Computer
cpu
cpu_id(pk)

table: Monitor
monitor_id(pk)
serial_number
monitor_type
purchase_date
manuf

table: cpu_monitor_pair
cpu_monitor_pair_id (pk)
monitor_id (fk) references Monitor
cpu_id (fk) references Computer

table: equipment_in_use
cpu_monitor_pair_id (fk) (pk)
user_id (fk) (pk)

ok Vagrant this is what i am trying to do:

i want to keep try for administrative purposes to keep track of the users in our office, their passwords, email address and computer they are using. realitive to the computer they are using i want to keep track of specifics like cpu, ram, motherboard, serail_number, monitor used. i know i need another table to hold similar infomation for the monitors.

In this case it should be different... 'monitor' beeing instance, where 'model' beeing just a model. Purchase date moved to 'monitor' (it's instance-specific).

table: Computer
cpu
monitor_id(fk)

monitor
monitor_id(pk)
serial_number
monitor_type(fk)
purchase_date
Note: serial number may be id, but SNs are not always ints and don't have a 'standard' form, so integer id, separate from SN may be a good idea.

monitor model
monitor_type(pk)
manufacturer
color, parameters etc