Restoring select databases/tables from an --all-databases backup

[Raffi]

I use the --all-databases switch to backup my entire database.
Sometimes there's a need to restore individual databases or tables form
the backup file. What command should I use for this?

Thanks,
Raffi

[Bill Turczyn]

Re: Restoring select databases/tables from an --all-databases backup


Taken from: Linux Server Hacks
By Rob Flickenger

Here is a method for restoring a single mysql table from a huge
mysqldump

Like a good admin, you faithfully dump your mysql tables every night,
and save them to the filesystem in compressed form (presumably to be
picked up by a backup script later). You probably have something like
this running in cron on your database server (or one of its replicated
slaves):

for x in `mysql -Bse show databases`; do
mysqldump $x | gzip -9 > /var/spool/mysqldump/$x.`date +%Y%m%d`.gz
done


This will cover you if anything catastrophic happens to your live
database. But if your database grows to an appreciable size, doing
partial restores can be difficult. On a database with several million
rows, your dumps suddenly become massive piles of data that need to be
sifted through. How can you easily restore a single table out of a
several hundred megabyte compressed dump?

Here's a simple method using Perl. Create a script called
extract-table, with this in it:

#!/usr/bin/perl -wn
BEGIN { $table = shift @ARGV }
print if /^create table $table\b/io .. /^create table (?!$table)\b/io;


To extract the User table from the dump of a database called randomdb,
try something like this:

# zcat /var/spool/mysqldump/randomdb.200209 01.gz | extract-table Users[color=blue]
> ~/[/color]
Users.dump


Now you can restore your Users table with a simple:

# mysql randomdb -e "drop table Users"
# mysql randomdb < ~/Users.dump

[Raffi]

Re: Restoring select databases/tables from an --all-databases backup

Bill Turczyn wrote:[color=blue]
> Taken from: Linux Server Hacks
> By Rob Flickenger
>
> Here is a method for restoring a single mysql table from a huge
> mysqldump
>
> Like a good admin, you faithfully dump your mysql tables every night,
> and save them to the filesystem in compressed form (presumably to be
> picked up by a backup script later). You probably have something like
> this running in cron on your database server (or one of its[/color]
replicated[color=blue]
> slaves):
>
> for x in `mysql -Bse show databases`; do
> mysqldump $x | gzip -9 > /var/spool/mysqldump/$x.`date +%Y%m%d`.gz
> done
>
>
> This will cover you if anything catastrophic happens to your live
> database. But if your database grows to an appreciable size, doing
> partial restores can be difficult. On a database with several million
> rows, your dumps suddenly become massive piles of data that need to[/color]
be[color=blue]
> sifted through. How can you easily restore a single table out of a
> several hundred megabyte compressed dump?
>
> Here's a simple method using Perl. Create a script called
> extract-table, with this in it:
>
> #!/usr/bin/perl -wn
> BEGIN { $table = shift @ARGV }
> print if /^create table $table\b/io .. /^create table[/color]
(?!$table)\b/io;[color=blue]
>
>
> To extract the User table from the dump of a database called[/color]
randomdb,[color=blue]
> try something like this:
>
> # zcat /var/spool/mysqldump/randomdb.200209 01.gz | extract-table[/color]
Users[color=blue][color=green]
> > ~/[/color]
> Users.dump
>
>
> Now you can restore your Users table with a simple:
>
> # mysql randomdb -e "drop table Users"
> # mysql randomdb < ~/Users.dump[/color]

That's exactly what is happening and many times only specific
tables/databases get corrupted and it's inefficient to restore the
complete database structure. I'll try the script out as soon as I get a
chance. I guess mysql doesn't have a built in feature that resores
individual tables and databases from a full backup and leaves
everything else alone.

Raffi