[mysqld]
# 安装目录
basedir=D:\\mysql-8.0.12-winx64
# 数据存放目录
datadir=D:\\mysqlData\\data

mysqld --defaults-file=D:\mysql-8.0.12-winx64\my.ini --initialize --console

>mysqld --defaults-file=D:\mysql-8.0.12-winx64\my.ini --initialize --console
2018-08-20T16:14:45.287448Z 0 [System] [MY-013169] [Server] D:\mysql-8.0.12-winx64\bin\mysqld.exe (mysqld 8.0.12) initializing of server in progress as process 5012
2018-08-20T16:14:45.289628Z 0 [ERROR] [MY-010457] [Server] --initialize specified but the data directory has files in it. Aborting.
2018-08-20T16:14:45.299329Z 0 [ERROR] [MY-010119] [Server] Aborting
2018-08-20T16:14:45.301316Z 0 [System] [MY-010910] [Server] D:\mysql-8.0.12-winx64\bin\mysqld.exe: Shutdown complete (mysqld 8.0.12) MySQL Community Server - GPL.

D:\mysql-8.0.12-winx64\bin>mysqld --defaults-file=D:\mysql-8.0.12-winx64\my.ini --initialize --console
2018-08-20T16:15:25.729771Z 0 [System] [MY-013169] [Server] D:\mysql-8.0.12-winx64\bin\mysqld.exe (mysqld 8.0.12) initializing of server in progress as process 18148
2018-08-20T16:15:43.569562Z 5 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: L-hk!rBuk9-.
2018-08-20T16:15:55.811470Z 0 [System] [MY-013170] [Server] D:\mysql-8.0.12-winx64\bin\mysqld.exe (mysqld 8.0.12) initializing of server has completed

>mysqld --console
2018-08-20T16:18:23.698153Z 0 [Warning] [MY-010915] [Server] 'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
2018-08-20T16:18:23.698248Z 0 [System] [MY-010116] [Server] D:\mysql-8.0.12-winx64\bin\mysqld.exe (mysqld 8.0.12) starting as process 16304
2018-08-20T16:18:27.624422Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed.
2018-08-20T16:18:27.793310Z 0 [System] [MY-010931] [Server] D:\mysql-8.0.12-winx64\bin\mysqld.exe: ready for connections. Version: '8.0.12' socket: '' port: 3306 MySQL Community Server - GPL.

>mysql -u root -p
Enter password: ************
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 11
Server version: 8.0.12

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Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';
Query OK, 0 rows affected (0.13 sec)

mysql> show databases;
+--------------------+
| Database  |
+--------------------+
| information_schema |
| mysql  |
| performance_schema |
| sys  |
+--------------------+
4 rows in set (0.08 sec)

mysql> CREATE DATABASE lite;
Query OK, 1 row affected (0.19 sec)

mysql> USE lite;
Database changed

mysql> CREATE TABLE t_user (user_id BIGINT NOT NULL, username VARCHAR(20));
Query OK, 0 rows affected (0.82 sec)

mysql> SHOW TABLES;
+----------------+
| Tables_in_lite |
+----------------+
| t_user  |
+----------------+
1 row in set (0.00 sec)

mysql> DESCRIBE t_user;
+----------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------+-------------+------+-----+---------+-------+
| user_id | bigint(20) | NO | | NULL | |
| username | varchar(20) | YES | | NULL | |
+----------+-------------+------+-----+---------+-------+
2 rows in set (0.00 sec)

mysql> INSERT INTO t_user(user_id, username) VALUES(1, '老卫');
Query OK, 1 row affected (0.08 sec)