The links in convertException gives 404, i'm not 100% if I updated them correct, or if the e.g. should be update to 8.0 already.

https://dev.mysql.com/doc/refman/8.0/en/server-error-reference.html
https://dev.mysql.com/doc/refman/8.0/en/client-error-reference.html

When following error message is shown, then it will get converted to the
correct Exception classs of NotNullConstraintViolationException:

  PDOException: SQLSTATE[HY000]: General error: 1364 Field '...' doesn't have a
  default value

it is best practice to implement retry logic for transactions that are aborted because of deadlocks or timeouts. this makes such method available inside the DBAL and also add detection for errors where retrying makes sense in the different database drivers