Solved

PreparedStatement update does not update on NULL values

Posted on 2014-04-06
3
48 Views
Last Modified: 2016-06-04
Hi Experts

I am trying to update a field with NULL values without success, but If I put an empty String the update works. The problem with putting an empty string is - my column field "fruitname" accepts unique values. I am using JDBC. see below what I am trying to do.

update fruits_tbl set uxservernames=concat(fruitname, \r\n'" + fruitname + "') where fruit_id=" +fruit_id)

The columns

fruit_id (INT) PRK | fruitname (VARCHAR(255) | fruitdescr VARCHAR(255)|

The fruitname column can hold a NULL value.

Thank you.
0
Comment
Question by:jw124210
[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 Comments
 
LVL 35

Accepted Solution

by:
Dan Craciun earned 95 total points
ID: 39981728
CONCAT returns NULL if any of the operators are NULL.

If you want to avoid this, us
CONCAT_WS('\r\n', fruitname, 'peach')

CONCAT_WS will simply skip any NULL values.

HTH,
Dan
0
 
LVL 110

Expert Comment

by:Ray Paseur
ID: 39982795
In my experience MySQL NULL does not match an empty string of zero length.   However if the columns are defined NOT NULL DEFAULT '' an empty string will match.
0

Featured Post

Windows Server 2016: All you need to know

Learn about Hyper-V features that increase functionality and usability of Microsoft Windows Server 2016. Also, throughout this eBook, you’ll find some basic PowerShell examples that will help you leverage the scripts in your environments!

Question has a verified solution.

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

I use MySQL for many of my development projects in a Windows environment. To manage my databases (and perform queries) for years I used a tool called MySQL administrator.  This tool has since been replaced by MySQL Workbench. So I decided to m…
Foreword This is an old article.  Instead of using the MySQL extension that was used in the original code examples, please choose one of the currently supported database extensions instead.  More information is available here: MySQLi / PDO (http://…
Finding and deleting duplicate (picture) files can be a time consuming task. My wife and I, our three kids and their families all share one dilemma: Managing our pictures. Between desktops, laptops, phones, tablets, and cameras; over the last decade…

737 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