Title: Database
Last modified: September 21, 2022

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# Database

 *  Resolved [norbou](https://wordpress.org/support/users/norbou/)
 * (@norbou)
 * [3 years, 8 months ago](https://wordpress.org/support/topic/database-106/)
 * I would like to ask how big the index is or where to check it. We have over 85,000
   images, so we need to consider that. Also, it would be great if the hash was 
   created immediately on upload, which I guess is how it works, as various optimization
   plugins can change the files beyond recognition. However, it makes sense to use
   this plugin from the start, because the hashes of optimized images are actually
   useless to us, and it’s a question of whether that’s the reason it didn’t find
   a single duplicate file, even though I found over 3,000 (completely identical)
   by the offline method.

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Author [cornershop](https://wordpress.org/support/users/cornershop/)
 * (@cornershop)
 * [3 years, 6 months ago](https://wordpress.org/support/topic/database-106/#post-16246173)
 * Thanks for asking, we’ll investigate and have an update as soon as possible.
 *  Plugin Author [cornershop](https://wordpress.org/support/users/cornershop/)
 * (@cornershop)
 * [3 years, 6 months ago](https://wordpress.org/support/topic/database-106/#post-16265698)
 * Hi norbou,
 * Thanks for reaching out about this, we had a developer investigate and this was
   his feedback:
 * “The index” is really spread across many rows in the postmeta database table.
   To see how much disk or memory space the index is consuming, check the size of
   all rows in the wppostmeta table where metakey begins with ‘mdd_’.
 * Hashes are calculated on upload, and then recalculated any time an attachment
   post’s ‘_wp_attached_file’ meta value is changed. That’s by design – in most 
   cases we’ve observed, when the ‘_wp_attached_file’ value changes, it’s because
   a user has edited an image using WP’s built-in image editor, or used a plugin
   like Enable Media Replace to swap in a different file. Replaced, cropped, or 
   otherwise edited versions of an image are not “duplicates” of the original image,
   and are not treated as such by Media Deduper.
 * So yes, if you’re using an image optimizer that does not produce identical output
   when given identical input, the optimized images will not be identical, the hashes
   will not be identical, and Media Deduper won’t treat the images as identical.”
 * Thanks again for reaching out about this and let us know if you have any other
   questions.

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Database’ is closed to new replies.

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 * 2 replies
 * 2 participants
 * Last reply from: [cornershop](https://wordpress.org/support/users/cornershop/)
 * Last activity: [3 years, 6 months ago](https://wordpress.org/support/topic/database-106/#post-16265698)
 * Status: resolved