We are doing a bit of data rescue from a venerable, non-FMP source. Odd results on FMP file size and indexing contributions tho'.
File size, imported data, full indexing: 825 Mb
File size, compressed copy 1: 539 Mb
Make a fresh copy, switch off all indexes and uncheck the option to rebuild them. Save a compressed copy.
File size, compressed copy 2: 539 Mb (unexpected)
File size, clone: 256 kb
File size, using clone and importing data from Compressed copy 2: 719 Mb (very unexpected, no indexes)
File size, Compressed copy 3: 539 Mb (mmm)
This would suggest that
a) indexes have no overhead (highly implausible), or
b) indexing parameters are ignored
Bug, or really special feature? (***Windows 7; file size figures via Properties)
All the best,