MS-SQL in General :: Databases

Databases
InterBase (29)
MS-SQL (5)
mysql (37)
Oracle (1)

Tricks how to deal with Microsoft SQL Server (MS-SQL).

Articles:

This list is sorted by recent document popularity (not total page views).
New documents will first appear at the bottom.

Featured Article

How can I simulate a deadlock for testing purposes?

Question:

How can I simulate a deadlock for testing purposes?

Answer:

Below is a quick recipe for a dead lock. Two transactions, one first updating table 1, then 2 and the other one doing it in reverse order.

Both transactions wait in the middle for 20 seconds to give you some time to execute them 'simulaneously'.

When you run the two in transactions in two windows 'at the same time', you'll only have to wait ~20 seconds, and one of the windows will experience a dead lock.

CREATE TABLE t1 (i int);
 CREATE TABLE t2 (i int);
 
 INSERT t1 SELECT 1;
 INSERT t2 SELECT 9;
 
 
 /* in one window enter: */
 BEGIN TRAN
 UPDATE t1 SET i = 11 WHERE i = 1
 WAITFOR DELAY '00:00:20'
 UPDATE t2 SET i = 99 WHERE i = 9
 COMMIT
 
 /* in a second window (another transaction) enter: */
 BEGIN TRAN
 UPDATE t2 SET i = 99 WHERE i = 9
 WAITFOR DELAY '00:00:20'
 UPDATE t1 SET i = 11 WHERE i = 1
 COMMIT

Most recent comments

2009-11-07 12:00:16:
by anonymous
in Dating Scams
on Dating scammer Rhoda Naa from Accra, Ghana:

Je pense que dans l'amour, nous devons se lancer avec notre cœur, et non pas réfléchir pour trouver absolument un raisonnement. La seule raison de l'Amour c'est en notre cœur et non pas dans notre ... read more

2009-11-07 11:59:28:
by [hidden]
in Dating Scams
on Dating scammer Osei Kwesi Accra Ghana kind_osei@hotmail.com from Accra, Ghana:
END OF ARELATIONSHIP

Thishis illustrates a typical bit of minor scamming Saymehi

2009-11-07 11:57:24:
by anonymous
in Dating Scams
on Dating scammer Vida Awabu:
I have a lot of pictures of this scammer esther ansomaa, rahinatu or what ever she calls herself. and would be happy to share them

2009-11-07 11:45:33:
by anonymous
in Passwords
on Need password for encrypted RAR or ZIP archive:
The Hangover[2009]DvDrip-aXXo what is password for this torrent.

2009-11-07 11:29:08:
by OJAS
in Dating Scams
on Is this Russian girl scamming me? How to recognize scammers:
@RealMadrid,
Dirk is helping us, he WON'T get scammed, no worries there. But the concern should be for the Brasileiro, he maybe a newbie, cold lose money, simply for emailing to a photo, and some ... read more

2009-11-07 10:59:47:
by venezolano
in Dating Scams
on Dating scammer Anna Ogannisyan:
I think that lopitropi7777@yahoo.com is trying to get fishes in the middle of the Sahara desert. If Boris was a little bit smarter, he should make a change.

Perhaps it is hunting season
... read more

2009-11-07 10:00:28:
by anonymous
in Dating Scams
on Dating scammer Osai Williams from Ghana:

is she a scammer?
she write me on tagged.com
iam not sure,she want married me and children

2009-11-07 09:55:44:
by srt8
in Dating Scams
on Dating scam artist Sindy Becky Green in Ashley, Ohio (Lagos, Nigeria):

this is jessica scottman the above one is jamie Peterson

2009-11-07 09:32:05:
by anonymous
in Dating Scams
on Various dating scammers:

confirmed fake and scammer by russian embassy in london

2009-11-07 08:45:17:
by srt8
in Dating Scams
on Scam Artist Anna from Yoshkar-Ola:

and yet another of JESSICA SCOTTMAN UK who is she really?


	Search: