Num 1. MySQL5.7導出數據時提示--secure-file-priv解決辦法：
問題分析
在官方的文檔中，對secure_file_priv進行了說明，它用於限制數據的導出。
- secure_file_priv 為 NULL 時，表示限制mysqld不允許導入或導出。
- secure_file_priv 為 /tmp 時，表示限制mysqld只能在/tmp目錄中執行導入導出，其他目錄不能執行。
- secure_file_priv 沒有值時，表示不限制mysqld在任意目錄的導入導出。
在Mysql中輸入命令show variables like '%secure_file_priv%';可以看到默認secure_file_priv = NULL。
mysql> show global variables like '%secure_file_priv%';
+------------------+-------+
| Variable_name | Value |
+------------------+-------+
| secure_file_priv | NULL |
+------------------+-------+
解決辦法
1. 檢查support-files文件夾（路徑 /usr/local/mysql/support-files 這是Mac中的隱藏文件夾，在Finder下shift+command+g然后輸入路徑），是否有my.cnf配置文件，在Mac中好像是默認不存在該文件（具體不清楚），需要我們自己手動配置Mysql。
2. （關閉Mysql）需要在 /etc下配置my.cnf，首先 cd /etc，然后手動配置，vim my.cnf，輸入以下配置信息。
# Example MySQL config file for medium systems. # # This is for a system with little memory (32M - 64M) where MySQL plays # an important part, or systems up to 128M where MySQL is used together with # other programs (such as a web server) # # MySQL programs look for option files in a set of # locations which depend on the deployment platform. # You can copy this option file to one of those # locations. For information about these locations, see: # http://dev.mysql.com/doc/mysql/en/option-files.html # # In this file, you can use all long options that a program supports. # If you want to know which options a program supports, run the program # with the "--help" option. # The following options will be passed to all MySQL clients [client] default-character-set=utf8 #password = your_password port = 3306 socket = /tmp/mysql.sock # Here follows entries for some specific programs # The MySQL server [mysqld] character-set-server=utf8 init_connect='SET NAMES utf8 port = 3306 socket = /tmp/mysql.sock skip-external-locking key_buffer_size = 16M max_allowed_packet = 1M table_open_cache = 64 sort_buffer_size = 512K net_buffer_length = 8K read_buffer_size = 256K read_rnd_buffer_size = 512K myisam_sort_buffer_size = 8M character-set-server=utf8 init_connect='SET NAMES utf8' secure_file_priv= # Don't listen on a TCP/IP port at all. This can be a security enhancement, # if all processes that need to connect to mysqld run on the same host. # All interaction with mysqld must be made via Unix sockets or named pipes. # Note that using this option without enabling named pipes on Windows # (via the "enable-named-pipe" option) will render mysqld useless! # #skip-networking # Replication Master Server (default) # binary logging is required for replication log-bin=mysql-bin # binary logging format - mixed recommended binlog_format=mixed # required unique id between 1 and 2^32 - 1 # defaults to 1 if master-host is not set # but will not function as a master if omitted server-id = 1 # Replication Slave (comment out master section to use this) # # To configure this host as a replication slave, you can choose between # two methods : # # 1) Use the CHANGE MASTER TO command (fully described in our manual) - # the syntax is: # # CHANGE MASTER TO MASTER_HOST=<host>, MASTER_PORT=<port>, # MASTER_USER=<user>, MASTER_PASSWORD=<password> ; # # where you replace <host>, <user>, <password> by quoted strings and # <port> by the master's port number (3306 by default). # # Example: # # CHANGE MASTER TO MASTER_HOST='125.564.12.1', MASTER_PORT=3306, # MASTER_USER='joe', MASTER_PASSWORD='secret'; # # OR # # 2) Set the variables below. However, in case you choose this method, then # start replication for the first time (even unsuccessfully, for example # if you mistyped the password in master-password and the slave fails to # connect), the slave will create a master.info file, and any later # change in this file to the variables' values below will be ignored and # overridden by the content of the master.info file, unless you shutdown # the slave server, delete master.info and restart the slaver server. # For that reason, you may want to leave the lines below untouched # (commented) and instead use CHANGE MASTER TO (see above) # # required unique id between 2 and 2^32 - 1 # (and different from the master) # defaults to 2 if master-host is set # but will not function as a slave if omitted #server-id = 2 # # The replication master for this slave - required #master-host = <hostname> # # The username the slave will use for authentication when connecting # to the master - required #master-user = <username> # # The password the slave will authenticate with when connecting to # the master - required #master-password = <password> # # The port the master is listening on. # optional - defaults to 3306 #master-port = <port> # # binary logging - not required for slaves, but recommended #log-bin=mysql-bin # Uncomment the following if you are using InnoDB tables #innodb_data_home_dir = /usr/local/mysql/data #innodb_data_file_path = ibdata1:10M:autoextend #innodb_log_group_home_dir = /usr/local/mysql/data # You can set .._buffer_pool_size up to 50 - 80 % # of RAM but beware of setting memory usage too high #innodb_buffer_pool_size = 16M #innodb_additional_mem_pool_size = 2M # Set .._log_file_size to 25 % of buffer pool size #innodb_log_file_size = 5M #innodb_log_buffer_size = 8M #innodb_flush_log_at_trx_commit = 1 #innodb_lock_wait_timeout = 50 [mysqldump] quick max_allowed_packet = 16M [mysql] no-auto-rehash # Remove the next comment character if you are not familiar with SQL #safe-updates default-character-set=utf8 [myisamchk] key_buffer_size = 20M sort_buffer_size = 20M read_buffer = 2M write_buffer = 2M [mysqlhotcopy] interactive-timeout
3. sudo chmod 644 my.cnf，將該配置文件的讀寫執行權限改為644。（推薦每次修改該配置文件后都重新設置644權限）
4. 打開Mysql，輸入 show variables like '%secure_file_priv%';可以看到secure_file_priv = 空。
mysql> show variables like '%secure_file_priv%';
+------------------+-------+
| Variable_name | Value |
+------------------+-------+
| secure_file_priv | |
+------------------+-------+
1 row in set (0.00 sec)
Num2. MySQL導入數據顯示“Error code:13. Can't get stat of ‘ ’（Permission denied）”解決辦法：
解決辦法：
在解決"secure-file-priv"問題后，導入數據時再次碰見錯誤。在google后找到解決辦法。
將load data infile 改為 load data local infile。錯誤即可解決（具體原因不清楚）
Num3. MySQL導出數據顯示“Can't create/write to file ‘Users/***’（Errcode:13）”解決辦法：
問題分析：
這應該是關於MySQL臨時文件目錄的問題，為解決這個問題做了很多嘗試，在my.cnf配置臨時文件目錄，並給予該文件777權限等等都沒有解決問題。
解決辦法：
最后同樣在google上找到解決辦法。如下圖
這是由於權限問題，因為試圖讓mysql用戶將數據寫入私人主目錄。我們可以在usr/local下創建一個文件夾，用來保存從mysql中導出的數據。
2019-06-30 18:03:14
Num4. 關於MySQL5.7下初始密碼
問題分析：
安裝Mysql5.7完成后，Mysql會隨機給定一個初始密碼。
Num5. MySQL啟動出現“MySQL server PID file could not be found!
Starting MySQL...The server quit without updating PID file (/usr/local/mysql/data/rekfan.pid).”解決辦法
問題分析：
比較詳細的分析見https://blog.csdn.net/zalion/article/details/9274263
解決辦法：
就我自己的嘗試而言，以下三種情況可能性較大
1.可能是/usr/local/mysql/data/rekfan.pid文件沒有寫的權限
解決方法 ：給予權限，執行 “chown -R mysql:mysql /var/data” “chmod -R 755 /usr/local/mysql/data” 然后重新啟動mysqld
2. 可能進程里已經存在mysql進程
解決方法：用命令“ps -ef|grep mysqld”查看是否有mysqld進程，如果有使用“kill -9 進程號”殺死，貌似在最后還會剩下一個進程，mysqld。
3. mysql在啟動時沒有指定配置文件時會使用/etc/my.cnf配置文件，請打開這個文件查看在[mysqld]節下有沒有指定數據目錄(datadir)
解決方法：請在[mysqld]下設置這一行：datadir = /usr/local/mysql/data。希望用Mac的同學，安裝好Mac之后就配置好my.cnf（新建位於/etc/下）
2019-07-08 18:33:25 更新