MySQL and Yii2 GridView: filtering in Russian becomes case-sensitive?

Question

MySQL

There is a table on MySQL 5.7 with utf8mb4_unicode_ci encoding and model, search model, CRUD generated to it using Gii.
On the index.php form, there is a standard GridView with filtering by fields. Only words in English are case-insensitive, and in Russian - case-sensitive, which I don't need at all.
The debugger shows that in requests the words are sent to the database in the same form as I wrote, that is, Yii2 does not seem to convert anything.
Tell me what can be done? I suspect it's MySQL? Everywhere I use utf8mb4_unicode_ci encodings
UPD: Just looked, I have commented out the charset in the Yii2 config for the base, I thought it was taken from the base, but suddenly not? I tried to put 'utf8' and 'utf8mb4' - all Russian text turns into scribbles. What is set there by default?
UDP2: added 'charset' => 'utf8mb4' to the connection settings, created an entry with the text 'Test', now searches regardless of case. It seems that all the data will have to be re-imported in order to get up under the encoding ... but it seemed that everything worked ...

Answer 1

It turned out that the problem was in the database connection settings, namely, I commented out the explicit setting of the font encoding.

'db' => [
            'class' => 'yii\db\Connection',
            ...
            'charset' => 'utf8mb4',
            ...
        ],

Explicitly setting the encoding turned all Russian records from the database into scribbles, but exporting and importing data again (this was done using Yii2 tools) solved everything.

Answer 2

How to implement case insensitive search in MySQL?
rmcreative.ru/blog/post/utf8_unicode_ci-ili-utf8_g...