Comments on: SQL – Truncate and Delete http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/ feel the passion of technologies here! Fri, 06 Nov 2009 20:05:45 +0000 http://wordpress.com/ hourly 1 By: Preethi http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-719 Preethi Thu, 19 Feb 2009 04:56:48 +0000 http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-719 Fentastic! I found the absolute differences bet' the TRUNCATE and DELETE commands. No one author provided such a correct answer for this question. Its very useful for the beginners. Thank you very much! Fentastic! I found the absolute differences bet’ the TRUNCATE and DELETE commands. No one author provided such a correct answer for this question. Its very useful for the beginners. Thank you very much!

]]> By: Trushar http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-711 Trushar Fri, 23 Jan 2009 16:50:18 +0000 http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-711 Hi Prashant Nice explanation. But hope you can answer couple of questions I have on this. Truncate does not delete data. Truncate just deallocates pages and stores this information in log file. 1) If data is not deleted then does that mean that data still exist somewhere? 2) In truncate, if data is not deleted and only pages gets deallocated(information of which is stored in log file), then why is it that we cannot use rollback to reallocate these pages? Hi Prashant

Nice explanation. But hope you can answer couple of questions I have on this.

Truncate does not delete data. Truncate just deallocates pages and stores this information in log file.

1) If data is not deleted then does that mean that data still
exist somewhere?

2) In truncate, if data is not deleted and only pages gets
deallocated(information of which is stored in log file),
then why is it that we cannot use rollback to reallocate
these pages?

]]> By: using truncate table | keyongtech http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-707 using truncate table | keyongtech Sun, 18 Jan 2009 16:52:30 +0000 http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-707 [...] back the transaction? > > truncate is *minimaly* logged, that doesn't mean it isn't :-) http://techahead.wordpress.com/2007/...te-and-delete/ « SQL Server Management Studio | Select Distinct with a twist [...] [...] back the transaction? > > truncate is *minimaly* logged, that doesn’t mean it isn’t :-) http://techahead.wordpress.com/2007/…te-and-delete/ « SQL Server Management Studio | Select Distinct with a twist [...]

]]> By: ramu http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-701 ramu Tue, 13 Jan 2009 16:21:20 +0000 http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-701 Very useful indeeeeeedddddddd............. Very useful indeeeeeedddddddd………….

]]> By: Gops http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-610 Gops Wed, 13 Aug 2008 06:39:48 +0000 http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-610 Hi RAMESH M Yes you can. As explained in above article. Hi RAMESH M

Yes you can. As explained in above article.

]]> By: Gops http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-609 Gops Wed, 13 Aug 2008 06:06:34 +0000 http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-609 Hi Prashant, In case I am not worried about FK constraints / triggers, then is there any difference between TRUNCATE and DELETE in terms of performance of following step (INSERT). For this step, I understand TRUNCATE will be faster but If I want to reload (INSERT) almost the same number of records, will my INSERT be faster and compensate for time I lost in DELETE (compared to TRUNCATE)? Any scenario where DELETE ALL will be preferred over TRUNCATE, other than logging or ones you covered above? Thanks for your article anyways. Hi Prashant,

In case I am not worried about FK constraints / triggers, then is there any difference between TRUNCATE and DELETE in terms of performance of following step (INSERT). For this step, I understand TRUNCATE will be faster but If I want to reload (INSERT) almost the same number of records, will my INSERT be faster and compensate for time I lost in DELETE (compared to TRUNCATE)? Any scenario where DELETE ALL will be preferred over TRUNCATE, other than logging or ones you covered above?
Thanks for your article anyways.

]]> By: RAMESH M http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-596 RAMESH M Mon, 28 Jul 2008 13:48:04 +0000 http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-596 Can we Rollback the data after using Truncate statement... Reply pls.... Can we Rollback the data after using Truncate statement…

Reply pls….

]]> By: RAMESH M http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-595 RAMESH M Mon, 28 Jul 2008 13:45:59 +0000 http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-595 Its very useful article.... Many many Thanks.... Its very useful article….

Many many Thanks….

]]> By: Jeff M http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-587 Jeff M Wed, 16 Jul 2008 16:34:02 +0000 http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-587 Any idea why a truncate on a table would throw a foreign key constraint error but a delete of all rows on the same table works fine? I verified that all FK tables had no rows in them when I truncated. Is it possible you cannot truncate a table that has FK's? Any idea why a truncate on a table would throw a foreign key constraint error but a delete of all rows on the same table works fine? I verified that all FK tables had no rows in them when I truncated. Is it possible you cannot truncate a table that has FK’s?

]]> By: Sushil Khajuria http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-573 Sushil Khajuria Wed, 02 Jul 2008 05:59:29 +0000 http://techahead.wordpress.com/2007/10/10/sql-truncate-and-delete/#comment-573 Hi, Thanks for such a detailed article about differences b/w DELETE and TRUNCATE. I had searched this many times on net but the explaination given here is far more better, useful and best part is written in such a way that even a layman can understand with just one reading. Good Work Prashant........ Hi,

Thanks for such a detailed article about differences b/w DELETE and TRUNCATE. I had searched this many times on net but the explaination given here is far more better, useful and best part is written in such a way that even a layman can understand with just one reading.

Good Work Prashant……..

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