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Have decided Micros**t help is about as much use as a chocolate tea pot.
How do you assign multiple keys in tables?
The 'help' thing tells me all about the intricacies of keys etcetera, but leaves out one vital part HOW DO I DO IT!!!
Any help gratefully received :)
(smiling thorugh clenched teeth)
You can't AFAIK.
AFAIK??
As Far As I Know :(
Cheers.
I'd imagine that it was possible, as the help explains all about it.
I've also managed it in MySQL.
Sorry. I use too many acronyms. Lol.
My ICT teacher swears that you can't have two primary keys, and he usually knows what he's talking about. :p
you can't have two primary keys...
But...
http://www.sqlmag.com/Articles/Index...leID=5113&pg=1Quote:
Each table has one and only one primary key, which can consist of one or many columns. A concatenated primary key comprises two or more columns. In a single table, you might find several columns, or groups of columns, that might serve as a primary key and are called candidate keys. A table can have more than one candidate key, but only one candidate key can become the primary key for that table.
Access is too primative to support this I believe. MS SQL Server and others can do it however.
Cheers Shad
:(
Will have to set up an autonumber key
Can't have multiple primary keys. Can have a composite primary key....
Any idea how to do that Rythmic?
In table designer hold down ctrl and then click in the leftmost column (the record selector) to highlight the fields you want to be part of your key. Whilst keeping ctrl pressed right click over your selection and select 'Primary key'.
If you don't keep ctrl pressed when you right click it will only use the field the mouse is currently over.
Cheers Mart,
I was releasing Ctrl before i right clicked.
Hexus Forums - the source for infinite knowledge :D
Bizaar how Access requires that, but SQL Enterprise manager doesn't...
I used Access as part of my AVCE ICT course, I hated it with a passion.
TBH - it's a pain in the arse if you're used to more upmarket dbs. But if compare it with other consumer level stuff, it's not bad.
Yes I know MySQL is free, but it's not something that Joe bloggs will understand. I'd rather use MySQL myself (if oracle or ms sql is not available.
I've used MySQL at uni, hence the reason this appears to be such a steep learning curve!! I'm doing a military project where they don't trust free stuff at the moment :(
They'd rather spend the taxpayers money on inferior stuff :D
Do I detect a certain amount of snobbery here? Horses for courses. Not everyone requires an all singing all dancing SQL database for enterprise use with thousands of users, warehousing and data mining.
Access is a rapid development tool and it is pretty good at it. Remember, Access isn't the database, it's the front end - Jet is the database.
Thats the point I was trying to make - Access is fantastic in it's own space, and has very - just don't try and run anything too complicated off of it. I personally hate the fact you can't even do simple stuff like subqueries, but thats cause I've got used to better things ;) Hopefully they'll ditch Jet in newer versions and use MSDE instead.
jaow83 - have you thought about using the MSDE instead, if the military won't stretch to MS-SQL proper?
What do you define as too complicated? If something is technically complicated, you probably have a point but a lot of things in life are not that complicated when you break it down.
I had an Access Document Control system and Commercial Management system for a £200m construction job - a semi conductor plant. Bits of it were complex and it had up to 16 simultaneous users (two front end programs each linked to three database back ends - didn't even realise that I couldn't do sub-queries (what are they anyway?). I take it that it's not a query based on a query based on another one?
It's when you're trying to do something like:
select customer,(select sum(total) from orders where order.custumerFK=customers.customerID) AS totalspent FROM customers
OK - it's not the way I'd do this in real life - it's just an example (you could do this particular example much easier and quicker). I've just realised I haven't used Access since '97 so maybe they've added that now. It's something they've added recently in MySQL (they had promised it for the last three versions, IIRC).
I also hate the way you can't define a foreign key of the tables own primary key (grrr).
I have seen an huge amount of systems based on access, and nothing turns out interfaces so quick.
The current project I'm working in is a content management system, interface is web based, for ~50 simultaneous editors, distributed worldwide, and ~1500 simultaneous content readers 24/7/365. I wouldn't like to even attempt that on Access!