Tuesday, August 13, 2013

How to clear all data in a column in a MySQL database table

In certain cases its essential to clear all data in a particular column in a table.
For example a database name is school
There is a table inside school is student
A column inside school is email 

Column email contains email ids of about 100 students.
Apply following command, if you want to clean all email id entries from email column.

mysql -uroot -p  [enter mysql root password]

You can get mysql command prompt, enter following commands there;

use school;
UPDATE `student` SET `email` = '';
quit;



Now email column inside student table is clean.

Tuesday, August 6, 2013

Sunday, August 4, 2013

How to find CPU architecture information

In certain situations, you have to find PC architecture (32 bit / 63 bit) for various purposes. Here is a simple command to display Linux architecture information.

lscpu

The result is,