bash scripting for mysqldump - bash

Question

i use the following code to download all mysql database in a different file and not in one file (like --all-databases) and put them in the /backup/mysql folder
#!/bin/bash
mysqldump=`which mysqldump`
echo $mysqldump
mkdir /backup/mysql/$(date '+%d-%b-%Y')
echo "creating folder for current date done"
for line in "$(mysqlshow |cut -f1 -d"-" | cut -c 3- | cut -f1 -d" ")"
do
$mysqldump $line > /backup/mysql/$(date '+%d-%b-%Y')/"$line"
echo "$line\n"
done
I used the cut pipes to remove dashes and empty space before and at the end of the database name and it gave me what I want.
The problem is at line 13 according to bash but with no more details. Any ideas what I'm doing wrong?

Answer 1

mysqlshow output format
+---------------------+
| Databases |
+---------------------+
| information_schema |
| gitlabhq_production |
| mysql |
| performance_schema |
| phpmyadmin |
| test |
+---------------------
Your script doesn't manage the first 3 lines nor the last one, so you $line variable is invalid.
Solution
mysql | tail -n +4 | head -n -1 | tr -d '| '
tail -n +4: skip first four lines (may need adjustement);
head -n -1: ignore last line ;
tr -d '| ': remove pipe and space.
Advices
quotes your variables ;
use $() instead of backtick ;
don't use for i in $(ls *.mp3).
read How can I read a file (data stream, variable) line-by-line (and/or field-by-field)?
Better solution
Instead of a for loop you should use a while with a Process Substitution:
while read -r db; do
echo "[$db]";
done < <(mysqlshow -u root -p | tail -n +3 | head -n -1 | tr -d ' |' )