Solved

Foreign Key Constraints fail dumping and restoring MySQL db

Posted on 2013-01-25
6
1,205 Views
Last Modified: 2013-03-11
Hi all,

When I dump a MySQL db data to a .sql file from phpmyadmin and try to restore to the loca version of the db on my machine i get the following error;

Error Code 1452. Cannot add or update child row. a foreign key constraint fails.


Now I assume this is because it is trying to insert the data out of sequence (for example trying to insert a relationship table such as userole before user table is populated??)

Is there a way of clmbatting this when we dump the data?
0
Comment
Question by:flynny
[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
  • 3
  • 2
6 Comments
 
LVL 143

Expert Comment

by:Guy Hengel [angelIII / a3]
ID: 38819411
Either you create the constraints after the data loading, or you make indeed shure you load in the correct order. You might find that you can disable the constraints during the loading.
0
 
LVL 24

Accepted Solution

by:
johanntagle earned 500 total points
ID: 38821750
Open the dump file with a text editor and put this somewhere at the top:

SET FOREIGN_KEY_CHECKS=0;

Remember to do a SET FOREIGN_KEY_CHECKS=1; after.
0
 

Author Comment

by:flynny
ID: 38821772
ok temporarily releasing the constraints sounds the most straight forward idea.

How is it possible to do this using mysql workbench please?
0
Salesforce Made Easy to Use

On-screen guidance at the moment of need enables you & your employees to focus on the core, you can now boost your adoption rates swiftly and simply with one easy tool.

 
LVL 24

Expert Comment

by:johanntagle
ID: 38821839
You can type in that line and run it like any SQL statement.

But I suggest you make it part of the dump file, which you can open as an SQL script in Workbench or using by any text editor.
0
 

Author Comment

by:flynny
ID: 38885476
ok could you provide the code to remove and then readd these constraints?

i.e. I assume I would use the code to remove constrainsts

Insert the data,

dump the constraints from the original db and re-add these back tot the copy db?
0
 
LVL 24

Expert Comment

by:johanntagle
ID: 38886604
Why remove and readd when you can just disable and re-enable them with the commands I gave above?
0

Featured Post

How our DevOps Teams Maximize Uptime

Our Dev teams are like yours. They’re continually cranking out code for new features/bugs fixes, testing, deploying, responding to production monitoring events and more. It’s complex. So, we thought you’d like to see what’s working for us. Read the use case whitepaper.

Question has a verified solution.

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

Since pre-biblical times, humans have sought ways to keep secrets, and share the secrets selectively.  This article explores the ways PHP can be used to hide and encrypt information.
A company’s centralized system that manages user data, security, and distributed resources is often a focus of criminal attention. Active Directory (AD) is no exception. In truth, it’s even more likely to be targeted due to the number of companies …
The viewer will learn how to look for a specific file type in a local or remote server directory using PHP.
Polish reports in Access so they look terrific. Take yourself to another level. Equations, Back Color, Alternate Back Color. Write easy VBA Code. Tighten space to use less pages. Launch report from a menu, considering criteria only when it is filled…

738 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