Hi im very new to linux,

Is it possible to compress the mysqldump output into say db_backup.sql.tgz. Then add that to an existing archive e.g. backup.tgz in one command or on the fly to save space and deleting it?

Thanks

A few things:

1) There is no reason to tar a single file, just zip it.

gzip db_backup.sql (which will yield db_backup.sql.gz)

2) There is no good way with a single command to add a file to a tgz/tarball. There are command lines that perform this action in a single command line, but that really isn't what you were asking for.

3) You're not stuck using tar/gzip (bzip2 generally gives better compression for example), you can zip, arj, arc, rar, etc in linux and each has different feature sets you can invoked for the task at hand and several those include adding files to an archive and better compression ratios and common availability on other platforms if you're looking for that.

Tar is a pretty old program that has long been used to store many files in a single file, but that wasn't its original purpose and sometimes it lacks features that reflect that. I do know there is a patch to allow you to add files to a tarball, but I've not used it.

Thanks for the information.

Yes I agree no need to tar the mysqldump thanks for pointing this out. Im using gzip because the files are over 3 Gig and saves on cpu and memory...so i have heard.

Could you gzip the mysqldump + files_backup.tgz to make a new gzip file in one command...e.g.

backup.gz contains:

files_backup.tar.gz <--- already exists
db_backup.gz or db_backup.sql

So to go over it again because im confusing myself

files_backup.tgz has already been made before I run mysqldump so dont need to create it.

Then from the mysqldump command gzip the sql file e.g. db_backup.gz or not. Then gzip both files sql & files_backup.tgz...???

Thanks again

Here... lets do it this way, operation order:

generate: database.sql
generate: file_backup.tgz
execute: tar cfvz new_backup.tgz database.sql file_backup.tgz

which will yield new_backup.tgz which contains two files database.sql and file_backup.tgz both of which will be compressed and realistically speaking if file_backup.tgz was only file_backup.tar it would probably be just as good because you wouldn't end up double compressing (thus saving a lot of cpu time.)

If you wanted you could gzip the database.sql
If you wanted to you could NOT gzip the file_backup.tgz (tar cfv (or whatever options except z or j)) and you'd still end up with a compressed tar'd archive once you made the new tarball.

You could also look at updating an existing tarball with incrementals... but that's a whole other beast.