Automate MySQL Monitoring with Shell Scripts and Cron: A Step‑by‑Step Guide

When performing routine operations and performance monitoring, shell scripts can be leveraged to interact with MySQL databases without entering the MySQL prompt. This guide shows how to configure a Bash script and schedule it with crontab to manage database objects.

Setup Variables

#!/bin/bash
HOSTNAME="192.168.111.84"   # database host
PORT="3306"
USERNAME="root"
PASSWORD="your_password"
DBNAME="test_db_test"        # database name
TABLENAME="test_table_test"   # table name

Create Database and Table

# Create database
create_db_sql="create database IF NOT EXISTS ${DBNAME}"
mysql -h${HOSTNAME} -P${PORT} -u${USERNAME} -p${PASSWORD} -e "${create_db_sql}"

# Create table
create_table_sql="create table IF NOT EXISTS ${TABLENAME} ( name varchar(20), id int(11) default 0 )"
mysql -h${HOSTNAME} -P${PORT} -u${USERNAME} -p${PASSWORD} ${DBNAME} -e "${create_table_sql}"

Insert, Query, Update, and Delete Data

# Insert data
insert_sql="insert into ${TABLENAME} values('billchen',2)"
mysql -h${HOSTNAME} -P${PORT} -u${USERNAME} -p${PASSWORD} ${DBNAME} -e "${insert_sql}"

# Query data
select_sql="select * from ${TABLENAME}"
mysql -h${HOSTNAME} -P${PORT} -u${USERNAME} -p${PASSWORD} ${DBNAME} -e "${select_sql}"

# Update data
update_sql="update ${TABLENAME} set id=3"
mysql -h${HOSTNAME} -P${PORT} -u${USERNAME} -p${PASSWORD} ${DBNAME} -e "${update_sql}"
mysql -h${HOSTNAME} -P${PORT} -u${USERNAME} -p${PASSWORD} ${DBNAME} -e "${select_sql}"

# Delete data
delete_sql="delete from ${TABLENAME}"
mysql -h${HOSTNAME} -P${PORT} -u${USERNAME} -p${PASSWORD} ${DBNAME} -e "${delete_sql}"
mysql -h${HOSTNAME} -P${PORT} -u${USERNAME} -p${PASSWORD} ${DBNAME} -e "${select_sql}"

By placing the above script in a file and adding an entry to crontab, the commands can run automatically at desired intervals, providing continuous monitoring and management of MySQL data without manual intervention.