truncate vs. delete

Everybody knows: TRUNCATE is fast, because it's a DDL, and it directly resets the highwater mark, and writes nothing in the rollback segments. 

So TRUNCATE is much faster than DELETE FROM.

I just tried to measure time difference on my laptop, using SET TIMING ON, manipulating data in a table containing 200'000 records.

13:39:48 SQL> create table my_table
 (id number primary key,
  text varchar2(20)
  ); 
   Table created. 
   Elapsed: 00:00:00.03 
13:40:48 SQL> begin 
13:41:01 2 for i in 1 .. 200000 loop 
13:41:01 3 insert into my_table (id, text) values(i, 'text' || i); 
13:41:01 4 end loop; 
13:41:01 5 end; 
13:41:01 6 / 
   PL/SQL procedure successfully completed. 
   Elapsed: 00:00:28.48 
13:41:29 SQL> commit; 
   Commit complete. 
   Elapsed: 00:00:00.03 
13:41:41 SQL> truncate table my_table; 
   Table truncated. 
   Elapsed: 00:00:00.48 
13:41:58 SQL> begin 
13:42:14 2 for i in 1 .. 200000 loop 
13:42:14 3 insert into my_table (id, text) values(i, 'text' || i); 
13:42:14 4 end loop; 
13:42:14 5 end; 
13:42:14 6 / 
   PL/SQL procedure successfully completed. 
   Elapsed: 00:00:21.41 
13:42:37 SQL> commit; 
   Commit complete. 
   Elapsed: 00:00:00.01 
13:42:40 SQL> delete from my_table; 
   200000 rows deleted. 
   Elapsed: 00:00:08.63 
13:42:55 SQL> commit; 

 Bottom line : TRUNCATE is immediate, DELETE runs during 8 seconds.

Google account on Mac

Recently, I was confronted by a little annoyance while using my google account. I just enabled 2-factors authentication, and a while after, I noticed that I couldn't sync ma iPad's and Mac's iCal app. I also couldn't create fresh accounts. I read this post ... and everything was solved. The point is that some app do not handle login to google correctly when 2-factors authentication is enabled. By configuring app-specific passwords in Google accounts, the problem is solved. I just hadn't realized this, because I use 2 google accounts (one is private, the other is for work), and right after enabling 2-factors authentication on the first account, I also configured app-specific paswords for Mac -iCal and iPhone just for that one account, leaving the other partially configured.