How many times it has happened that somebody asks u a difference of Truncate and Delete,Atleast i am the person who used to say the very first point is that "TRUNCATE CAN NOT BE ROLLED BACK" untill i came across the blog post of Pinal Dave
So,the best way to understand any point is start with sample,here what we will do is we will create one table and we will create one transaction and under which we will be doing our truncate thing...and finally we will observe the result
Lets us start it by creating sample table and our transaction like following as shown below
Now if you just copy and paste this above in your query editor and hit F5 (RUN),you would be surprise to see that even if you have performed TRUNCATE operation on your table,your data are still available at the end of transaction if we ROLLBACK
I was also got the feeling of learning something new with this helpful post by Pinal,which inspired me to write this post,so that we can use it for further reference
i hope this post is larning for you people as well
comments are welcomed...:-D
So,the best way to understand any point is start with sample,here what we will do is we will create one table and we will create one transaction and under which we will be doing our truncate thing...and finally we will observe the result
Lets us start it by creating sample table and our transaction like following as shown below
CREATE TABLE temp (Name varchar(50)) INSERT INTO temp SELECT 'Moe' INSERT INTO temp SELECT 'Larry' INSERT INTO temp SELECT 'Curley' BEGIN TRAN SELECT * FROM temp TRUNCATE TABLE temp SELECT * FROM temp ROLLBACK TRAN SELECT * FROM temp DROP TABLE temp
Now if you just copy and paste this above in your query editor and hit F5 (RUN),you would be surprise to see that even if you have performed TRUNCATE operation on your table,your data are still available at the end of transaction if we ROLLBACK
I was also got the feeling of learning something new with this helpful post by Pinal,which inspired me to write this post,so that we can use it for further reference
i hope this post is larning for you people as well
comments are welcomed...:-D
@Daivagna,
ReplyDeletethis was really strange behavior.
I couldn't digest the fact tht values are being retrieved even after truncate.
thanx a lot 4 sharing this strange but correct information.
keep it up...
wow mind boggling..
ReplyDeletei searched on google for these kind of Example but i did not get...
after i saw it i could understand real use of Roll back practically...
thanks sir.....