Category Archives: MySQL

configure: error: libmysqlclient is needed for MySQL support

When i install pureftpd with mysql support on CentOS 7 server, i get following error This is because MySql dev packages are missing on the server. Fixed by installing


Repair MySQL MyISAM Database with myisamchk

myisamchk is a command line tool to repair MySQL MyISAM database. You need to run it a user root. To repair all MyISAM tables in a database, run Example [root@localhost ~]# myisamchk –recover /var/lib/mysql/w3blogs/wp_blogs – recovering (with sort) MyISAM-table ‘/var/lib/mysql/w3blogs/wp_blogs’


MySQL Slow Query Log

MySQL Slow Query Log i used to find SQL query that are slow. To enable Slow Query Log, add following to /etc/my.cnf file under [mysqld] section. If you don’ have folder /var/log/mysql/, create it Now restart MySQL or


InnoDB: mmap(x bytes) failed; errno 12

On a VPS, MariaDB refused to start with error [root@ip-10-0-51-171 mariadb]# service mariadb start Redirecting to /bin/systemctl start mariadb.service Job for mariadb.service failed because the control process exited with error code. See “systemctl status mariadb.service” and “journalctl -xe” for details.


Repair MySQL database with mysqlcheck

mysqlcheck command can be used to check, repair, optimize or analyzes tables in a MySQL database. To check a database for errors, run If you database need user name and password, specify it with -u USER-NAME -p, for example This


PHP can’t connect to MySQL running on localhost

On a server, PHP can’t connect to MySQL with following code, it returned error “Could not connect: Permission denied 2002” If i change “localhost” with IP address 127.0.0,1, PHP script is able to connect to MySQL server properly. If i


MySQL Configuration

Here are some of the configurations for MySQL, some of these are already set on your server. When you edit MySQL configuration file (/etc/my.cnf or /etc/mysql/my.cnf), you need to restart MySQL as it is only read when you start MySQL.


InnoDB Error log file ib_logfile0 is of different size

After copying MySQL data (/var/lib/mysql) folder from one server to another, MariaDB failed to start. On checking log, found following error InnoDB: Error: log file ./ib_logfile0 is of different size 0 268435456 bytes InnoDB: than specified in the .cnf file


MySQL Can’t open and lock privilege tables

Recently on of the server had its HDD failed. After moving MySQL data (/var/lib/mysql) to another server MySQL (MariaDB) would not start. On checking log file, i got following errors 170314 14:48:09 Percona XtraDB (http://www.percona.com) 5.5.49-MariaDB-38.0 started; log sequence number


Secure MySQL Installation with mysql_secure_installation

On Ubuntu 16.04, after MySQL (MariaDB) installed, you have no root password. Root is able to login with out any password. To set root password for MySQL, after installation, run You will be asked to set new password, also allow