Trigger: Looping though multiple rows in the deleted table?

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Trigger: Looping though multiple rows in the deleted table?

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Jeff Moden SSC Guru Points: 1003869 More actions · Answer 1

... and, yes... that "feeling" goes towards delete triggers, as well.

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

Lloyd Harrison SSC Veteran Points: 237 More actions · Answer 2

Hi Jeff,

Thanks for all your help with this. I feel the same way you do with the CASCASE. I think it is the wrong way to go. But I'am just a messanger.

Anyway, I think I found the issue:

Table ZIP

PK_ID

ZIP

STATE

Table 2 DISTRICT

PK_ID

DISTRICT_NAME

FK_ZIP

Table 3 SCHOOL

PK_ID

SCHOOL_NAME

FK_DISTRICT

FK_ZIP

I see the problem here, but on the other hand, I don;t see a problem here.

If I delete the ZIP, I want to delete the SCHOOL and DISTRICT

If I delete the DISTRICT I want to delete the SCHOOL

Makes sense, right?

GSquared SSC Guru Points: 260824 More actions · Answer 3

Yes, it makes sense, but SQL sees it as a possible infinite loop. It isn't, but the code has to err on the side of false positives in this case.

Either manage it with a trigger, or, better yet, in the proc that deletes districts. (Keeping it in the proc helps document it and makes it easier to refactor/maintain.)

I agree with Jeff that deletion usually needs to be in the code. I've had a few instances where I couldn't, and had to do it with triggers, but in those cases I make sure it's documented and that the trigger raises severity 10 errors, so testing the proc makes those messages visible.

- Gus "GSquared", RSVP, OODA, MAP, NMVP, FAQ, SAT, SQL, DNA, RNA, UOI, IOU, AM, PM, AD, BC, BCE, USA, UN, CF, ROFL, LOL, ETC
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darpanshah23 Valued Member Points: 67 More actions · Answer 4

Thanks for better solution with minimum lines of code.