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What do you think of my script to make an immediate DB and document root zip backup? Any flaw you might find. Please inform me of it:

#!/bin/bash
mysqldump -u root -p --all-databases | zip ${drt}/db-$(date +\%F-\%T).zip
zip -r all_zipped-$(date +\%F-\%T).zip ${drt}/ -x "*/cache/*"
rm -rf  ${drt}/db-$(date +\%F-\%T).zip

It is important to me to have the backup in document root because of comfortability. It's a small server environment (with external automatic backups) and I think it'll be redundant to have a backup dir just for once-in-a-while immediate backups I do with that nice script above.

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Bug?

It looks to me that the name of the zip file used in the first and the last command were intended to be the same, that is the ${drt}/db-$(date +\%F-\%T).zip part:

mysqldump ... | zip ${drt}/db-$(date +\%F-\%T).zip
...
rm -rf  ${drt}/db-$(date +\%F-\%T).zip

They will only be the same if the mysqldump and rm commands run within the same second.

Don't repeat yourself

If a non-trivial command is expected to return the same value every time you run it, then extract it to a variable. Not only to save unnecessary processing power, but also to keep the non-trivial logic in one place, so that it's easy to change if ever needed, in one place.

Double-quote command arguments

It's a good rule of thumb to double-quote command arguments when they contain variables, to protect yourself from unintended word splitting and glob expansions.

Useless flags

In rm -rf ${drt}/db-$(date +\%F-\%T).zip, since we're deleting a file, not a directory, the -r flag is useless. Avoid useless flags.

Alternative solution

I suggest to write like this:

#!/bin/bash

date=$(date +\%F-\%T)

mysqldump -u root -p --all-databases | zip "${drt}/db-$date.zip"
zip -r "all_zipped-$date.zip" "${drt}"/ -x "*/cache/*"
rm -f "${drt}/db-$date.zip"
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  • \$\begingroup\$ I didn't know how to handle that problem that problem of different timestamps in the files, for mysqldump ... | zip ${drt}/db-$(date +\%F-\%T).zipVS rm -rf ${drt}/db-$(date +\%F-\%T).zip. Thanks for showing a way and for the rest of the answer. I am fully aware that rf is redundant when it's a file; It was a mistake. I thank you dearly. I would thumb up both your answers if I could. I miss 5 points. \$\endgroup\$ – user9303970 Feb 10 '18 at 8:41

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