MySQL 报错 [ERROR] [FATAL] InnoDB: Table flags are 0 in the data dictionary but the flags in file

本地装了 Wamp 的环境，启动时 MySQL 启动失败，查看启动失败的日志，日志如下：

2021-08-21T12:46:57.183482Z 0 [ERROR] [FATAL] InnoDB: Table flags are 0 in the data dictionary but the flags in file .\ibdata1 are 0x4800!
2021-08-21 20:46:57 0xf48  InnoDB: Assertion failure in thread 3912 in file ut0ut.cc line 942
InnoDB: We intentionally generate a memory trap.
InnoDB: Submit a detailed bug report to http://bugs.mysql.com.
InnoDB: If you get repeated assertion failures or crashes, even
InnoDB: immediately after the mysqld startup, there may be
InnoDB: corruption in the InnoDB tablespace. Please refer to
InnoDB: http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html
InnoDB: about forcing recovery.
12:46:57 UTC - mysqld got exception 0x80000003 ;
This could be because you hit a bug. It is also possible that this binary
or one of the libraries it was linked against is corrupt, improperly built,
or misconfigured. This error can also be caused by malfunctioning hardware.
Attempting to collect some information that could help diagnose the problem.
As this is a crash and something is definitely wrong, the information
collection process might fail.

后来在网上查，很多人都是用了 MySQL 8 以后再用 MySQL 5.7 后报这个问题，然后我本地也是这种情况。后来我检查 my.ini 文件，发现其中有一项配置 datadir 的目录指向是有问题的，修改一下即可。

然后再次启动，报下面的错误：

2021-08-21T12:57:29.873841Z 0 [ERROR] InnoDB: The innodb_system data file 'ibdata1' must be writable
2021-08-21T12:57:29.874698Z 0 [ERROR] InnoDB: The innodb_system data file 'ibdata1' must be writable
2021-08-21T12:57:29.875239Z 0 [ERROR] InnoDB: Plugin initialization aborted with error Generic error
2021-08-21T12:57:30.090440Z 0 [ERROR] Plugin 'InnoDB' init function returned error.
2021-08-21T12:57:30.091251Z 0 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
2021-08-21T12:57:30.091811Z 0 [ERROR] Failed to initialize builtin plugins.
2021-08-21T12:57:30.092185Z 0 [ERROR] Aborting

然后按照网上的方法，删掉 MySQL 安装目录下的 data 目录下的 ib_logfile0 和 ib_logfile1 即可，如果这两个文件删除不掉，那么就在进程列表中找到 mysqld 将其结束即可。