Question

I have a database of about 6GB in size and it has a table with 12.6 million rows. I tried to export the database into a SQL dump by:

mysqldump -u root -p db_name > db_name.sql

When the command finishes, the exported SQL dump file is just about 2GB and the primary table got exported only about 1 million rows.

What could possibly be wrong?

Answer 1

There is a 2GB filesize limit for some reason, the easiest way to get around this is using split:

mysqldump ... | split -b 250m - filename.sql-

You can also compress the files like this:

mysqldump ... | gzip -9c | split -b 250m - filename.sql.gz-

To restore from a non-compressed file, do this:

cat filename.sql-* | mysql ...

For a compressed file:

cat filename.sql-* | zcat | mysql ...

Of course if you want a single file, you can then tar the result.

Obviously you can replace the 250m with a different size if you wish.