<a href="http://g.adspeed.net/ad.php?do=clk&zid=15220&wd=468&ht=60&pair=as" target="_blank"><img style="border:0px;" src="http://g.adspeed.net/ad.php?do=img&zid=15220&wd=468&ht=60&pair=as" alt="i" width="468" height="60"/></a>
Log in
::
Register
::
Not logged in
Home
Tags
Articles
Editorials
Stairways
Forums
Scripts
Videos
Blogs
QotD
Books
Ask SSC
SQL Jobs
Training
Authors
About us
Contact us
Newsletters
Write for us
<a href="http://g.adspeed.net/ad.php?do=clk&zid=15491&wd=120&ht=300&pair=as" target="_top"><img style="border:0px;" src="http://g.adspeed.net/ad.php?do=img&zid=15491&wd=120&ht=300&pair=as" alt="i" width="120" height="300"/></a>
Recent Posts
Recent Posts
Popular Topics
Popular Topics
Home
Search
Members
Calendar
Who's On
Home
»
Article Discussions
»
Article Discussions by Author
»
Discuss Content Posted by David Poole
»
Fast Project Rollbacks
22 posts, Page 2 of 3
««
1
2
3
»»
Fast Project Rollbacks
Rate Topic
Display Mode
Topic Options
Author
Message
David.Poole
David.Poole
Posted Wednesday, October 22, 2008 12:45 PM
SSCrazy
Group: General Forum Members
Last Login: 2 days ago @ 8:46 AM
Points: 2,750,
Visits: 1,410
doobya (10/22/2008)
Some very nice techniques and ideas in the article
But I have never rolled back a change to a production database in 10 years.
I rarely have to roll back a live deployment but deployments into a QA environment are another matter. And before anyone jumps up and down QA in this case is the environment where we throw testers and bloody minded users at systems to see if they can break the code.
As we move towards more agile practices the ability to rollback/deploy on the fly are important.
As far as tools are concerned you can use Red-Gate Compare and generate a snapshot of the schema. Cheap though the tool is not all companies see the benefit of buying a £400 tool against £x,000 in DBA time.
In terms of deleting columns from existing tables I take either the backup table approach or bcp the file and table create script out to a tape before I do it. It depends on how big the table is.
To be honest we are much more likely to add/change columns than delete them. When we do delete them we are pretty damn sure they will never be used again.
LinkedIn Profile
Post #590048
Alexander Kuznetsov
Alexander Kuznetsov
Posted Wednesday, October 22, 2008 2:48 PM
SSC Veteran
Group: General Forum Members
Last Login: Thursday, February 21, 2013 8:55 AM
Points: 219,
Visits: 807
Hi,
I can use something like SQL Compare which has been around for a while, has been thoroughly tested out by thousands of users, and probably does all (or almost all) this. Why should I spend my time on doing something which has been done before and works very well? Unless I am missing something, this sounds like reinventing the wheel. What am I missing?
Post #590119
hurcane
hurcane
Posted Wednesday, October 22, 2008 2:53 PM
SSC-Enthusiastic
Group: General Forum Members
Last Login: Monday, May 06, 2013 2:30 PM
Points: 143,
Visits: 191
Alexander Kuznetsov (10/22/2008)
Hi,
I can use something like SQL Compare which has been around for a while, has been thoroughly tested out by thousands of users, and probably does all (or almost all) this. Why should I spend my time on doing something which has been done before and works very well? Unless I am missing something, this sounds like reinventing the wheel. What am I missing?
SQL Compare does not generate "rollback" scripts. The article was not about deployment scripts. It was about writing rollback scripts to undo the changes that SQL Compare would generate.
Post #590125
Ninja's_RGR'us
Ninja's_RGR'us
Posted Wednesday, October 22, 2008 3:09 PM
SSC-Insane
Group: General Forum Members
Last Login: Yesterday @ 9:37 PM
Points: 21,359,
Visits: 9,542
Stupid question here... but what happens if you reverse the order of the servers just after creating the migration scripts?
Doesn't that help you create the rollback scripts.
I'm sure it won't put back lost or altered data, but if that's the only thing left to worry about, it seems like a great start to me.
Post #590140
Alexander Kuznetsov
Alexander Kuznetsov
Posted Wednesday, October 22, 2008 3:15 PM
SSC Veteran
Group: General Forum Members
Last Login: Thursday, February 21, 2013 8:55 AM
Points: 219,
Visits: 807
hurcane (10/22/2008)
Alexander Kuznetsov (10/22/2008)
Hi,
I can use something like SQL Compare which has been around for a while, has been thoroughly tested out by thousands of users, and probably does all (or almost all) this. Why should I spend my time on doing something which has been done before and works very well? Unless I am missing something, this sounds like reinventing the wheel. What am I missing?
SQL Compare does not generate "rollback" scripts. The article was not about deployment scripts. It was about writing rollback scripts to undo the changes that SQL Compare would generate.
SQL Compare absolutely does generate rollback scripts. I do just that every time I deploy: open up SQL Compare, generate deploy/rollback scripts, test them both out, check them in in Subversion etc.
Post #590146
Alexander Kuznetsov
Alexander Kuznetsov
Posted Wednesday, October 22, 2008 3:18 PM
SSC Veteran
Group: General Forum Members
Last Login: Thursday, February 21, 2013 8:55 AM
Points: 219,
Visits: 807
Just looked up in Subversion: more than one hundred rollback scripts, all generated by SQL Compare of course.
Post #590149
timothyawiseman
timothyawiseman
Posted Thursday, October 23, 2008 10:26 AM
Right there with Babe
Group: General Forum Members
Last Login: Thursday, February 14, 2013 12:01 PM
Points: 743,
Visits: 900
This was an excellent article and well written. And I cannot overemphasize the point you made about code readability. In fact, I think my team is getting tired of me talking about literate programming.
---
Timothy A Wiseman
SQL Blog:
http://timothyawiseman.wordpress.com/
Post #590605
Wayne West
Wayne West
Posted Thursday, October 23, 2008 10:51 AM
SSC Eights!
Group: General Forum Members
Last Login: Wednesday, May 09, 2012 10:26 AM
Points: 891,
Visits: 1,958
I teach readability by stressing that you're writing code for the person who follows you. It jolts their perception a bit to think that 'this previous project would have been so much easier if it had been better documented, so I'll document my current project better for the person who comes after me.'
Of course, some people, regardless of how well the case is argued, will never improve their documentation and readability. :D
Post #590622
jeffrey yao
jeffrey yao
Posted Saturday, October 25, 2008 1:06 AM
SSC Veteran
Group: General Forum Members
Last Login: 2 days ago @ 1:18 PM
Points: 215,
Visits: 610
I see what proposed in the article is an overkill most of time in SQL2K5 EE. For DB side rollback, is there anything better/quicker than the database snapshot? i.e. Do a db snapshot before the deployment, and if anything goes wrong, and you need to research, compare with the snapshot db, or if you want to rollback, rollback with the snapshot db.
Just my two cents... :)
Rgds,
JY
Post #591654
Ninja's_RGR'us
Ninja's_RGR'us
Posted Saturday, October 25, 2008 7:38 AM
SSC-Insane
Group: General Forum Members
Last Login: Yesterday @ 9:37 PM
Points: 21,359,
Visits: 9,542
jeffrey yao (10/25/2008)
I see what proposed in the article is an overkill most of time in SQL2K5 EE. For DB side rollback, is there anything better/quicker than the database snapshot? i.e. Do a db snapshot before the deployment, and if anything goes wrong, and you need to research, compare with the snapshot db, or if you want to rollback, rollback with the snapshot db.
Just my two cents... :)
Rgds,
JY
That's a good point Jeffrey, have you had any troubles with that method when you rolled back a failed deployement, any hints we need to know to use this method?
Post #591689
« Prev Topic
|
Next Topic »
22 posts, Page 2 of 3
««
1
2
3
»»
Permissions
You
cannot
post new topics.
You
cannot
post topic replies.
You
cannot
post new polls.
You
cannot
post replies to polls.
You
cannot
edit your own topics.
You
cannot
delete your own topics.
You
cannot
edit other topics.
You
cannot
delete other topics.
You
cannot
edit your own posts.
You
cannot
edit other posts.
You
cannot
delete your own posts.
You
cannot
delete other posts.
You
cannot
post events.
You
cannot
edit your own events.
You
cannot
edit other events.
You
cannot
delete your own events.
You
cannot
delete other events.
You
cannot
send private messages.
You
cannot
send emails.
You
may
read topics.
You
cannot
rate topics.
You
cannot
vote within polls.
You
cannot
upload attachments.
You
may
download attachments.
You
cannot
post HTML code.
You
cannot
edit HTML code.
You
cannot
post IFCode.
You
cannot
post JavaScript.
You
cannot
post EmotIcons.
You
cannot
post or upload images.
Copyright © 2002-2013 Simple Talk Publishing. All Rights Reserved.
Privacy Policy.
Terms of Use.
Report Abuse.
