Illegal mix of collations for operation 'concat'

Question

I\'m trying to execute this concat query in mysql

SELECT CONCAT(if(fName,fName,\'\'),Name) 
From Student

Error:

#127

Answer 1

Look like you have a miss use on the if statement there because it will resulting an undefined data type so the concat operation will fail as it different in data type. Try change the query by use ifnull instead.

Try this query instead:

SELECT concat(ifnull(fName,''),Name) From Student

see the demo here http://www.sqlize.com/kfy85j8f1e

for another reference read also http://forums.mysql.com/read.php?10,225982,225982#msg-225982