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remove null

Li Jenny
Ranch Hand

Joined: Apr 19, 2010
Posts: 57
how can i remove the null field in mysql because db store the null value.
when i retrieve it , then display 'null'
Satya Sakhinetipalli
Greenhorn

Joined: May 16, 2008
Posts: 7
Li Jenny wrote:how can i remove the null field in mysql because db store the null value.
when i retrieve it , then display 'null'

Can you provide more information about how are you reading the data from mysql? are you trying to display on jsp page?
Jeanne Boyarsky
internet detective
Marshal

Joined: May 26, 2003
Posts: 30370
    
150

Jenny,
Null is a valid value. What do you want to happen? You can check for a null String or call isNull to make something different happen.


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kv ruby
Ranch Hand

Joined: Jul 23, 2009
Posts: 38
Hi jenny,

You can use the following whil retrieving data.

SELECT name FROM Table WHERE address IS NOT NULL

or in java code

if( rs.next()!=null) //rs is object of ResultSet

and avoid the null appearing.


Regards, ruby kv
rubyshiv.blogspot.com
David Newton
Author
Rancher

Joined: Sep 29, 2008
Posts: 12617

kv ruby wrote:
or in java code

if( rs.next()!=null) //rs is object of ResultSet

That's incorrect in at least a couple of ways: rs.next() returns a boolean, and if having a null address is a normal condition, you wouldn't want to query on it or check if you didn't get any results--the issue (seems to be, anyway) that when the address value *is* null the original poster doesn't want "null" to show up for the user.
ss kumar
Greenhorn

Joined: Jan 14, 2004
Posts: 19
Couple of different ways.

Option 1: Add a constraint to the column to not allow null and insert an empty string. There may be other reasons for allowing null, but if not needed then don't allow.
Option 2: Handle in UI. Use conditional statement Eg: (value==null) ? "" : value;

kumar
 
It is sorta covered in the JavaRanch Style Guide.
 
subject: remove null