Kurinchi Blogger Scribbles ... » my.cnf

Linux: Case sensitive MySQL table names

kurinchilamp — Thu, 21 Jul 2011 00:11:29 +0000

When transitioning MySQL database from Windows to Linux, users often encounter issues related to case-sensitiveness. Windows is case-insensitive and Linux is case-sensitive.

In such scenarios when a database call is made after the application migration happens, users often run into errors which can send them in circles between the migration servers.

Solution to this problem is to add a single line of text under my.cnf (MySQL configuration file) under [mysqld]

lower_case_table_names=1

$ whereis my.cnf
/etc/my.cnf

$ vi my.cnf
…
…
[mysqld]
lower_case_table_names=1

Common Errors related to this issue

When the application is executed, users get “table not found” errors which is an indication of this error. You can verify the error by issuing the command

$ mysqladmin -uAdmin -pPass variables

and check for the value of lower_case_table_names.

MySQL: Default collation latin1_swedish_ci (swedish case insensitive)

kurinchilamp — Sat, 26 Mar 2011 15:41:51 +0000

When new fileds are created as variable characters they get stored as latin1_swedish_ci as default. To change the default collation users will have to manually select the collation of their choice from the mysql admin interface such as in the case of phpmyadmin or will have to denote it in sql queries.

To make a specific collation as the default, other option to give mysql an indication of it by having the needed collation name in my.cnf (mysql configuration) as shown below

Edit my.cnf:
[mysqld]
collation_server=latin1_general_ci

MySql command to set collation type when creating database is given below:

Latin1 encoding
CREATE DATABASE sampledb DEFAULT CHARACTER SET latin1 COLLATE latin1_general_ci;

UTF-8 encoding
CREATE DATABASE sampledb DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;

Once the encoding for the database is set, fields associated with the tables in our new database will take up default collation as the one set during the database creation.

MySQL: Can’t connect to local MySQL server through socket ‘/var/run/mysqld/mysqld.sock’

kurinchilamp — Fri, 05 Feb 2010 08:27:25 +0000

Reason why this error might occur:

i) Incomplete MySQL implementation
ii) MySQL setting mis-configuration

Solution:

root@myserver:/# vi /etc/mysql/my.cnf

Comment out the below line in my.cnf file to make MySQL listen on ALL interfaces
#bind-address = 127.0.0.1

root@myserver:/# netstat -tap | grep mysql
tcp 0 0 *:mysql *:* LISTEN 17785/mysqld

Note that above line which indicates MySQL listening on all interfaces.