UTF8MB4 issue with MySQL 8 and PyMySQL

Migrated issue, originally created by Danqing Liu (@danching)

Using MySQL 8 and PyMySQL 0.8.1 with SQLAlchemy 1.2.8.

e = create_engine('mysql+pymysql://account@localhost:3306/db?charset=utf8mb4')
e.connect()

~/lib/python3.6/site-packages/pymysql/cursors.py:170: Warning: (3719, "'utf8' is currently an alias for the character set UTF8MB3, which will be replaced by UTF8MB4 in a future release. Please consider using UTF8MB4 in order to be unambiguous.")
  result = self._query(query)

This doesn’t happen with MySQL 5. I’m already using utf8mb4, so I shouldn’t really see this.

Thanks!

[elisong]

my problem was solved according to: https://blog.csdn.net/u010457406/article/details/90440494

version: "3"
services:
  db:
    .......
    environment:
      - MYSQL_ROOT_PASSWORD=${MYSQL_ROOT_PASSWORD}
      - TZ=${TZ}
      - **LANG=C.UTF-8**

[danqing]

I’m just doing a migration (alembic 1.3.0, pymysql 0.9.3, sqlalchemy 1.3.10):

/Users/danqing/Developer/society-api/env/lib/python3.7/site-packages/pymysql/cursors.py:170: Warning: (3719, "'utf8' is currently an alias for the character set UTF8MB3, but will be an alias for UTF8MB4 in a future release. Please consider using UTF8MB4 in order to be unambiguous.")
  result = self._query(query)
alembic upgrade head
INFO  [alembic.runtime.migration] Context impl MySQLImpl.
INFO  [alembic.runtime.migration] Will assume non-transactional DDL.
...

My connect string is

mysql+pymysql://society@localhost:3306/society?charset=utf8mb4

And my env.py:

from alembic import context
from sqlalchemy import engine_from_config, pool

def run_migrations():
    url = "mysql+pymysql://society@localhost:3306/society?charset=utf8mb4"
    engine = engine_from_config(
        configuration={},
        url=url,
        poolclass=pool.NullPool
    )
    connection = engine.connect()
    context.configure(connection=connection, target_metadata=None)

    try:
        with context.begin_transaction():
            context.run_migrations()
    finally:
        connection.close()


run_migrations()