mysql - phpMyAdmin - #1267 - Illegal mix of collations for operation '<' -

mysql - phpMyAdmin - #1267 - Illegal mix of collations for operation '<' -

i getting error when trying run next sql:

select * syshealth 'timestamp' < date_sub(now(),interval 15 minute)

i getting next error:

#1267 - illegal mix of collations (utf8mb4_general_ci,coercible) , (latin1_swedish_ci,numeric) operation '<'

i have table , database collation set utf8_unicode_ci

i have read few articles already, , have tried top reply here, without success...

any more idea's?

edit: additional info - 'timestamp' column of type datetime

you need utilize ` (backtick) identify column if utilize single ' , treated string literal.

select * syshealth `timestamp` < date_sub(now(),interval 15 minute)

mysql phpmyadmin collation