MySQL5.7.28 初始化數據庫

1）初始化隨機密碼????mysqld --initialize?

[root@host-172-16-61-102 bin]# ./mysqld --initialize

2020-02-15T07:01:38.309015Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).

2020-02-15T07:01:38.309069Z 0 [Warning] '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.

2020-02-15T07:01:38.497402Z 0 [Warning] InnoDB: New log files created, LSN=45790

2020-02-15T07:01:38.541219Z 0 [Warning] InnoDB: Creating foreign key constraint system?

tables.

2020-02-15T07:01:38.553509Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: 02fb69c1-4fc1-11ea-8b4e-fa163d34f78d.

2020-02-15T07:01:38.556591Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened.

2020-02-15T07:01:38.980429Z 0 [Warning] CA certificate ca.pem is self signed.

2020-02-15T07:01:39.723869Z 1 [Note] A temporary password is generated for root@localhost: +:NoRLu2kwhd

生成的密碼是：+:NoRLu2kwhd

以上的指令，默認讀取配置文件/etc/my.cnf，需要/etc/my.cnf文件中指定了數據庫的地址，并且生成一個root用戶的密碼，還有如下的參數可以設置

--user=mysql? //生成指定用戶的密碼

--datadir=/opt/mysql/mysql/data? //指定生成的數據庫數據地址

--defaults-file=/opt/mysql/mysql/etc/my.cnf//指定讀取的配置文件，取代默認的配置

2）初始化空密碼????mysqld --initialize-insecure

啟動mysqld服務 ./mysqld --user=root

創建密碼

[root@host-172-16-61-102 bin]# mysql -uroot -p

//提示密碼輸入，直接回車

Welcome to the MariaDB monitor.? Commands end with ; or \g.

Your MySQL connection id is 11

Server version: 5.7.28 MySQL xxx

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

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

//為root創建密碼

MySQL [(none)]> set password = password("root");

Query OK, 0 rows affected, 1 warning (0.00 sec)

MySQL [(none)]> quit

注意：執行“mysqld? --initialize”報錯了。提示“initialize specified but the data directory has files in it. Aborting”，大意是提示/opt/mysql/mysql/data數據庫地址下有文件，導致無法初始化數據庫，這個時候，可以進入到該目錄，將所有的數據刪除，說明之前已經初始化過