Adding Keys to Tables

knight

Hi there,

I am just wondering what effect (performance wise) adding a new key to a table would have. The reason is, our client heavily uses the Job Budget Line table, yet a report that they desire would require me to add another key to this table.

A co-worker doesn't want me to do this because he believes the more keys in this particular table (or any heavily used table) will slow down the system. Therefore he doesn't believe its worthwhile for the sake of one report.

Therefore we are both curious in checking if adding keys does effect performance at all, or does it only effect hard disk space, etc?

gva

Hi,

we have a customer who is complaining about the speed of Navision. On the Item Ledger Entry there are many keys. We want to delete some of these keys to check wether the database will speed up.

One problem : we don't know which keys are necessary and which keys can be deleted without problems. <img border="0" title="" alt="[Frown]" src="images/smiles/icon_sad.gif" /> (

Luc_VanDyck

You could use the Navision Developers Toolkit to see which keys are being used in the application.

Sandra

There is a fine line in Navision between using enough keys to satisfy the system and using too many. Normally Navision is grateful for new key's but at the point you will be overloading the system and it will slow down the table. On our Item Ledger we have 27 keys and are hitting the end of the line. Therefore we should delete some keys, but up to about 20 keys it speeded up the system. However even with the 27 keys, if our users select the correct index it works quite well.
You can see the key-size allowed in the C/front developing manual. I know this answer is not very satisfying, but you should always be aware that Navision is not a system that buckles quickly. So after giving some more thought about wether the key is really necessary try it. If you find the key is slowing the system and you haven’t used it anywhere else delete it again, but I am sure it will not be necessary. :?

DenSter

I would also like to suggest that you investigate your keys and consider combining them or just adding a field to an existing key. Be careful though, you don't really want to insert a field into a key unless you know where it is used.