How to resolve MySQL deadlocks

Mysql deadlock.

Prepare the environment.

1. Confirm the database version.

mysql> select @@version;
+-----------+
| @@version |
+-----------+
| 5.7.30    |
+-----------+
1 row in set (0.00 sec)

2. Confirm the database isolation level.

mysql> select @@transaction_isolation;
+-------------------------+
| @@transaction_isolation |
+-------------------------+
| REPEATABLE-READ         |
+-------------------------+
1 row in set (0.00 sec)