MySQL IFNULL ELSE
Solution 1
Use COALESCE:
SELECT COALESCE(field_a, field_b)
COALESCE is an ANSI standard function that returns the first non-null value from the list of columns specified, processing the columns from left to right. So in the example, if field_a
is null, field_b
value will be displayed. However, this function will return NULL if there is no non-null value from the columns specified.
It's supported on MySQL (I've used it on 4.1), SQL Server (since v2000), Oracle 9i+...
Solution 2
and another way to skin that cat (flexible for not just null comparisons)...
select if(field_a is not null, field_a, field_b) from...
Solution 3
Yes, but it's just two parameters:
IFNULL(field_a,field_b)
If field_a
is not null, it will be returned. Otherwise field_b
will be returned.
Reference: IFNULL
mcgrailm
Hello, thanks for visiting my profile. I am a web developer at PSU. I started my carrier by learning applescript. Since then I've become familiar with PHP MySQL, javascript, jQuery as well. I have made use of other services that go hand and hand with those languages such as json,jsonp,ajax. I have some shell scripting experience and have dabbled in perl. Hopefully I have helped you with a question you or maybe you have help me with a question, thanks for stopping by.
Updated on July 08, 2022Comments
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mcgrailm almost 2 years
I have a select statement where I want to make the select conditional like this:
IFNULL(field_a, field_a, field_b)
so that it checks field a. If a is null then the select would be field b.
Is that possible ?
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Chuck Callebs almost 14 yearsI support the use of COALESCE as well.
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Apolo over 9 yearsBest answer. Allow to do
Select if(name is not null, CONCAT('name is : ',name),'');
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Andrew over 8 yearsSuch a clear explanation of how the function works... Thanks! Updated the broken link.
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Arda over 8 years
select IFNULL(column, 'default')
also works. See here: sqlfiddle.com/#!9/14b752/1/0 -
TommyAutoMagically almost 4 yearsPretty cool explanation of a function I'm not familiar with! However, for OP's question, using
IF()
is much more readable.