[help] - It´s a bug with CONCAT function ?

[Carlos Junior]

Hello,

Has appear an error when i try execute this SQL script. In the SQL i try concat any fields for make 'pre-formated' to php apresentation.

SQL:
@s := concat(date_format(h.time_start, '%H:%i'), ' at ', date_format(h.time_end, '%H:%i'), '(', upper(pla.description), ')' ) description_for_combo_box,

Error:
Error Code : 1271
Illegal mix of collations for operation 'concat'
(0 ms taken)

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