I have to delete over 90 million records, do I remove or maintain the transaction's SQLWARNING?
If you are deleting much of a table it is often better (faster, etc) to copy the table over without the 'old' rows:

CREATE TABLE new LIKE real;
INSERT INTO new
    SELECT * FROM real
        WHERE dt &gt; NOW() - INTERVAL 1 MONTH;
RENAME TABLE real TO old,
             new TO real;
DROP TABLE old;   -- or dump it for archive purposes


Better yet, make that new table PARTITIONed by day so that you can daily do the very fast DROP PARTITION to get rid of the month-old data and REORGANIZE PARTITION to get a new partition for tomorrow.  Details in http://mysql.rjweb.org/doc.php/partitionmaint

If you need to "dump" or "archive" the month-old partition, see the discussion on "transportable tablespaces".  (Note: MySQL 5.6 has one method and newer versions have another.)

Details on other deletion techniques:  http://mysql.rjweb.org/doc.php/deletebig