Want to win a PS4? Go Premium and enter to win our High-Tech Treats giveaway. Enter to Win

x
?
Solved

Truncate table

Posted on 2011-02-21
2
Medium Priority
?
384 Views
Last Modified: 2012-05-11
When you truncate a table does it automatically delete the child records or are the child's table FK consstraints disabled?
0
Comment
Question by:msimons4
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
2 Comments
 
LVL 77

Accepted Solution

by:
slightwv (䄆 Netminder) earned 2000 total points
ID: 34947781
Give me a chance to answer in the other question.

Truncate will not work if child rows exist.

When in doubt, create two cables and try it.
0
 
LVL 77

Expert Comment

by:slightwv (䄆 Netminder)
ID: 34947803
Here's a quick a simple test to show all this in action.

drop table tab1 purge;
create table tab1(col1 char(1) primary key);

drop table tab2 purge;
create table tab2(col1 char(1), constraint tab2_fk foreign key(col1)
references tab1(col1) on delete cascade);

insert into tab1 values('a');
insert into tab2 values('a');
commit;

truncate table tab1;
delete from tab1;
0

Featured Post

Free Tool: Site Down Detector

Helpful to verify reports of your own downtime, or to double check a downed website you are trying to access.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Introduction A previously published article on Experts Exchange ("Joins in Oracle", http://www.experts-exchange.com/Database/Oracle/A_8249-Joins-in-Oracle.html) makes a statement about "Oracle proprietary" joins and mixes the join syntax with gen…
From implementing a password expiration date, to datatype conversions and file export options, these are some useful settings I've found in Jasper Server.
This video shows how to copy a database user from one database to another user DBMS_METADATA.  It also shows how to copy a user's permissions and discusses password hash differences between Oracle 10g and 11g.
This video shows how to Export data from an Oracle database using the Original Export Utility.  The corresponding Import utility, which works the same way is referenced, but not demonstrated.

610 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question