Saving images to a database or filesystem on iPhone -

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what best approach if want of rows in database table have image. should add column type blob, or should keep reference image , add image in documents folder?

there both advantages , disadvantages storing image data (or other large chunks of binary data) in database. on upside:

  • all of app's data contained within single file
  • depending on database, may have option of transactional/atomic updates app's data, avoiding problems app data gets unexpected states during error conditions

the disadvantages are:

  • the db larger
  • there may optimizations associated working image data filesystem lost (e.g. - memory mapping)
  • the memory footprint working images may increased
  • depending on db granularity during writes, there may increased contention/blocking decreases speed @ db updated if 1 wanted make lot of separate, transactional/atomic changes quickly

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