Getting the shell script:
wget launchpadlibrarian.net

Running:
sh tuning-primer.sh

!/bin/sh

for dbname in mysqlshow | awk '{print $2}'
do
mysqlcheck $dbname ticket -Fq
done

call this shell script and find the errors

time sh check.sh | grep error

An example of shell script.
This will print numbers 0 to 500 in one line.

!/bin/bash

Z=0
LIMIT=500
while [ "$Z" -lt "$LIMIT" ]

do
echo -n "$Z... "
Z=$( expr $Z + 1 )
done
echo
exit 0

ping the address received from positional parameter

!/bin/bash

if [ $# -eq 0 ]
then
SITE="google.com"
else
SITE="$1"
fi

ping -c 2 $SITE > /dev/null
if [ $? != 0 ]
then
echo $(date +%F) ... Network Failure!
fi

Here is the script that will loop two thousand times and print the statement on the screen.

!/bin/sh

MAX=2000
i=1
echo " truncate table t1; "

while [ $i -le $MAX ]
do
echo " insert into t1(f1) values($i); "
i=expr $i + 1
done

The match operator is the tilde “~” which will match an expression in a record or field. In this example awk is used to search for a field, number 7, that matches “nologin”.

awk -F: '$7 ~ /nologin/' /etc/passwd
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin

!/bin/sh

for i in find /var/lib/mysql/test/ -name "Table1.*"
do
cp $i dirname $i'/test'basename $i
done

duplicate a table Table1 by coping the files if it is a MyISAM table.

Brace expansion is used to generate arbitrary strings. For e.g.
ls mysql*.0000{1..3}

will list the files like mysql.00001 mysql.00002 & mysql.00003

This can also be used for something like this...

cp mysql.log{,.bak}

cp mysql.log mysql.log.bak

cp $da.log{.bak,}

cp 2010-05-28.log.bak 2010-05-28.log

!/bin/sh

unset REPLY
until [[ $REPLY ]]; do read -p "Enter your name: "
done
echo "welcome $REPLY"

The safe way to change IFS in a 'while read' loop is:

while IFS=| read a b c
do
: whatever
done

validdate.sh script will look like this...

!/bin/sh

userdate=$1
date -d $userdate &> /dev/null
if [ $? -ne 0 ] ; then
echo You entered an invalid date, $userdate
else
echo The date $userdate is valid
fi

sh validdate.sh 2009-33-44

You entered an invalid date, 2009-33-44

test -s /var/log/mailme.txt
if [[ $? -eq 0 ]] ; then
The above 2 lines can be written in one line as shown below:

if [[ -z /var/log/mailme.txt ]]; then