asked on

How to make a trigger conditional

Hello SQL experts. I will be grateful for any help on this one.

I am trying to customise a package (Maximo) which uses MSSQL Server 7.

I haven't used SQL before, and I've had no training, so I'm struggling a bit.

I discovered "triggers" and have had some success using them.

The following code works OK to populate the field "author" when my user is inserting a new workorder record:

- - - - -
CREATE TRIGGER [labor_info_ins] ON [workorder]
FOR INSERT
AS

UPDATE workorder
SET author =
(SELECT name FROM labor
WHERE laborcode = changeby)
- - - - - - -

My question is:

How do I make it populate "author" only if "author" is null. In other words, if the user actually enters an author name I want to use that, but if they don't I want to populate it by accessing the labor table.

I hope it is OK that I have categorised this question as easy. I imagine it is probably simple for someone who knows what they are doing (unlike me). If you think I am being too miserly please say so and I will upgrade the points.

Thanks

Iain Macrae

ASKER CERTIFIED SOLUTION

Guy Hengel [angelIII / a3]

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MacRae

ASKER

Thanks very much angellll

It worked like a charm.

And thanks for pointing out the deficiency in my code - you have no doubt saved me some embarrassment. I kind of assumed that code in the trigger would only apply to the record being inserted, but I see now that this is not so.

As a sign of gratitude I have increased the points to 100.

Best Regards

Iain MacRae