Saving a compacted copy
When you save a compacted copy of a file, FileMaker Pro re-creates the entire database, fitting as much data into each block as possible. This copies the logical structure, or arrangement, into the new file and reclaims unused space. Compacting can be time consuming if the file is large, and it might be best accomplished as an overnight task.
To save a compacted copy:
You should have at least as much free space on your intended media as the size of your uncompressed file. It is not a good idea to fill any storage media to its maximum capacity.
Choose File menu > Save a Copy As.
In the “Create a copy named” dialog box, for Save a (Windows) or Type (OS X), choose compacted copy (smaller).
Click Save.