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Let me just start off this post saying if you're not interested in InnoDB tablespace internals, then this might not be the post for you. :)

At any rate, whilst examining individual tablespace files (the .ibd file created when running with innodb_file_per_table option enabled) in their binary format, I noticed the initial page size for a individual tablespace did not appear to be 16k (as the default InnoDB page size is 16k).

Upon examining the actual binary data stored in the data file (just create a basic table and insert 10 rows), you can see data is written at the very beginning of the file (position 0).

One can also see data appearing at several (4) other places in this file.

I was trying to sync up what I was seeing with these InnoDB internals:

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Sometime you may need to recover a table when all you have is the .ibd file. In this case, if you try to load it into a new instance, your likely to encounter some errors about the table id not matching. And there is not really a way around this.

However, I’ve found two work-arounds for this:

Note: You will need the .ibd file and the CREATE TABLE statement for each table you want to recover using these methods.

1. Simulate the internal InnoDB table counter. That is, create work tables (with innodb_file_per_table enabled) until you have the internal pointer of table id equal to (1 - id_of_ibd_table_you_need_to_restore). (See Method #1)
2. Manually hex edit the .ibd file, changing the table id. (See Method #2)

*Note: There are some internal structures with this meta information, so you’ll need to dump/import that data after you get it loaded, so you avoid unpleasantries that will inevitably …