Local database storage dtBase2 files


My databases are growing in size and quantity. I currently have local database files on my laptop and sync stores on my NAS via WebDav which works perfectly. Only problem is my local files are getting too big for my laptop HDD. If I purchase an external SSD drive could I move my local files to it and still allow sync via WebDav to my NAS through DTP which will still be on my laptop?

Many thanks

Indeed you can - and an external SSD would be a nice choice for this too.
Just make sure you close the databases for moving them. I’d suggest a File > Close Database > Close All, then move them.
In their new home, just double-click to open them.

Re: sync - the databases’ name and file path have no effect on syncing. Sync identifies databases by their UUID.

Great than thanks Jim. That’s a relief, is this a copy and paste? or create duplicate on SSD, backup and restore procedure?

I am very impressed by DTP. In fact just recommended it again (for the umpteenth time) today to a fellow historian who enquired about MS Access on a Mac. Do historian’s need complicated relational designs? No, your fast indexing and good use of smart groups does everything I need. I did use SQL Server when in business so I know about OLAP and database design. DTP gives me everything I need. For any casual observers I should point out that I have no connection to DevonThink’s business at all. It is brilliant and STABLE!

Thanks for the kind words!

That’s a relief, is this a copy and paste? or create duplicate on SSD, backup and restore procedure?

copy and paste ??!?!? This isn’t Windows!!! :open_mouth: :stuck_out_tongue: Sorry, I couldn’t resist. It almost always distinguishes Windows converts. :slight_smile: I personally would not copy and paste files on a Mac (unless you’re referring to text and images in documents), especially something as large as a database.

And I’d treat it much simpler than you’re suggesting…

  • If you want to copy a database, just drag and drop. It copies by default. You could then delete the copy after it has been opened successfully.
  • If you want to move a database, drag and drop while holding the Command key.

HaHa, Good spot; I ran a 40 seat windows IT system for 35 years!

Excellent, drag and drop it is… thank you.

In theory then, I can host 125 x 32GB databases on a 4TB SSD. What is the maximum you would advise to have open at any one time please before I am endangering speed or compromising stability? Or is this a trial and error issue?


This is a difficult question as it has to do with available resources, values which are in flux as the machine is used. Here are my thoughts on database size, bearing in mind these are comfortable limits, so YMMV:

Size in gigabytes isn’t the critical number. If you check out File > Database Properties > … for a given database, the number of words / unique words are more critical. On a modern machine with 8GB RAM, a comfortable limit is 40,000,000 words and 4,000,000 unique words in a database. (Note: This does not scale in a linear way, so a machine with 16GB wouldn’t necessarily have a comfortable limit of 80,000,000 words / 8,000,888 unique words.) So text content in a database is far more important.

  • If you have a database of images, it will have very few words but be large in gigabytes.
  • If you have a database of emails, it will have many words, but may be smaller in gigabytes.

The second one may perform more poorly as the number of words increases beyond the comfortable limit.

Smaller, more focused databases will generally perform better, Sync faster, and be more data-safe in the event of a catastrophe (avoiding the “all your eggs in one basket” problem) . They also give you the opportunity to close unused databases when you’re not using them. This frees up resources, not only for DEVONthink, but the rest of the system. I personally advocate closing unused databases. There’s no real benefit to using machine resources on data that’s not in active use.

Some related thoughts on this are in the built-in Help > Documentation > Getting Started > Building A Database > Adding your files

Aaaah… OK thank you Jim!

This makes a lot of sense since I have noticed a difference in performance between my ‘text transcription’ databases full of word docx’s, and my original document (similar sized) image databases full of PDF’s and JPGS.

I will print your reply off to stick in my DTP folder as a reminder.

Thank you so much for your fast and accurate replies; I’ll stop bothering you now!

Great product, great support. Many thanks

No worries and certainly no bother. :slight_smile:

  1. It’s my job, and…
  2. Can you tell I enjoy talking about our apps? :wink:

And you’re very welcome. Cheers!