Export MySQL Rows by Specific Range

[ilyons]

Hey all,

Some rows of a single table in a database that I administer manage to have gone missing. Not that big of a problem: I have a backup.

The issue is that there has been more information added since the old data was lost, so I can't do a wholesale replacement. I've isolated the range of rows that were removed based on the primary key, but I'm not sure about the rest of the steps:

1) Export the rows based on the unique row id number;

2) Re-import the old rows without disturbing the new data.

Anyone have some wisdom for me?

Many thanks,
Ian

[smantscheff]

It all dependes. Does your table has relations to other tables? Is the primary key used as a foreign key elsewhere? Do you have orphaned records in relations?
If all this is no problem, the easiest way would be this:
Restore the backup table in a backup database (here called backup).
Then

insert ignore into mytable
select * from `backup`.mytable;

That way no new information will be overwritten, and all lost records will be restored.

[ilyons]

Hey smatscheff,

This looks like it'll do the trick. I'll run it now on a test DB and see how that works out. Many thanks for your advice. I'll mark this solved as soon as I get the records copied over.