Oh, yeah!! Svn is very bad, woodlouse…..
What I see on the Internet are solutions to pediatrics problems that can be accessed by modifying permissions, which are totally invalid for this problem! So go on goooole… And see this article
http://www.mobibrw.com/?p=369
Try it. The same dog blood doesn’t work. Svnadmin: Error opening BDB environment handle for file system “repo/DB”
Fortunately, there is a good habit of daily backup, restore it, and then
Export the original repository as a dumpfile
svnadmin dump path/to/old-repo > dumpfile
Import the dumpfile into the new repository
svnadmin load path/to/new-repo < dumpfile