HowTo Drop All Tables in MySQL Database Using BASH

Sohail Riaz — Mon, 03 Aug 2009 10:17:26 +0000

In this howto i will describe how to execute MySQL commands on BASH shell and do more on results. The beauty of BASH is that you can developed a script which help you to do different, repeated and can execute different MySQL commands on result of previous MySQL command result. My primary example is to drop all tables in MySQL database using BASH shell.

1) Check Number of Databases.

mysql -u root -p -e “SHOW DATABASES”

+————————-+
Database
+————————-+
information_schema
Randydb
test
mysql
+————————-+

2) Check the Number of Tables in a Database

mysql -u root -p -e “SHOW TABLES from mysql”
+—————————+
Tables_in_mysql
+—————————+
columns_priv
db
func
help_category
help_keyword
help_relation
help_topic
host
proc
procs_priv
tables_priv
time_zone
user
+—————————+

3) Drop All Tables in a Database

There is no single command for dropping all tables on mysql prompt. You can drop table one by one. To drop all tables we can script it using bash

mysql -u root -p -e “SHOW TABLES FROM Randydb” | grep -v “Tables_in_Randydb” | while read a; do
mysql -u root -p -e “DROP TABLE Randydb.$a”
done

The above script will drop all tables in Randydb. In this way you can create several small scripts to maintain / manage / monitor your MySQL. I am creating new mysql-bash scripts as per need and will post as soon as there is any new one.

How To Install MyTOP – a top clone for MySQL

Sohail Riaz — Tue, 02 Jun 2009 08:57:54 +0000

In this howto i will describe how to install mytop package on CentOS 5.3. MyTOP is top command clone to monitor mysql performance including queries, threads etc. You can get source of it from here to build or you can use rpmforge repositories for pre-build rpms. The machine i used to demonstrte is in production and getting very high mysql access, its running on CentOS 5.3.

1 Setting Up RPMForge Repository

RPMForge repository (http://dag.wieers.com) is the biggest rpm respository for RHEL, CentOS for all versions. To enable RPMForge respository run following command. The following command directly install rpm from http://dag.wieers.com site.

rpm -Uhv http://apt.sw.be/redhat/el5/en/i386/rpmforge/RPMS/rpmforge-release-0.3.6-1.el5.rf.i386.rpm

This rpm will add necessary files in our repository configuration and can be viewed at /etc/yum.repos.d/rpmforge.repo

2 Install MyTOP

Use yum to install mytop on your machine

yum -y install mytop

It will install mytop with all necessary pre-requisite to run mytop.

3 Running MyTOP

To run use

mytop

if you have restricted access using password then

mytop -u root -p -h localhost

NOTE: You may get following error in CentOS 5.3
Error in option spec: “long|!”

To fix this do following.

chmod 755 /usr/bin/mytop
vi /usr/bin/mytop

Search for the line

“long|!” => \$config{long_nums},

Change it to by commenting using #

#”long|!” => \$config{long_nums},

Now run the command again and it will run fine and you can see mytop giving all the information about you mysql server.