mysql creating view column as utf8_bin instead of utf8_general_ci

Question

I'm trying to create a view for my database.

CREATE VIEW `latest` AS
SELECT r.id as recheck_id, f.id as failure_id, r.`when`,
case
    when r.description like _utf8'dummy' then f.description
    else r.description
end as description,
case
    when r.technician_id is null then f.technician_id
    else r.technician_id
end as technician_id,
case
    when r.technician_id is null then f.tname
    else r.name
end as tech_name,
case
    when r.technician_id is null then f.tsurname
    else r.surname
end as tech_surname,
f.customer_id, f.name as cust_name, f.surname as cust_surname, f.area,
case
    when r.telephone is null then f.telephone
    else r.telephone
end as telephone, mobile,
f.appliance_id, f.type, f.model, f.brand,
f.budget, f.advance_payment, f.final_price
FROM rechecks_with_info r
left join failures_with_info f on f.id = r.failure_id
where `when` =
(select max(r2.`when`)
from rechecks r2
where r.failure_id = r2.failure_id)
order by `when` desc;

Everything works fine, until I try to search for a string inside the description column

I get an Illegal mix of collations (utf8_bin,NONE) and (utf8_general_ci,COERCIBLE) for operation 'like' error.

I checked the collation of the specific column and it is indeed set to utf8_bin by default. All other columns are in utf8_general_ci.

Is there a way I can specify the collation I want for the specific column in the view?

I have tried adding a specific collation after the description column definition and I got and error.

Answer 1

I figured out the problem a while ago and thought of sharing.

It turns out that the table columns the two descriptions where read from were not of the same collation. One was utf8_general_ci and the other utf8_unicode_ci. Their mixing produced a utf8_bin collated column.

Using the same collation for the two tables produced the correct results.