-V Write the library version number to the standard output, and exit.
-e Display information about the database environment.
-f Display information about the environment freelist. If -ff is given, summarize each freelist
entry. If -fff is given, display the full list of page IDs in the freelist.
-n Display the status of an LMDB database which does not use subdirectories.
-r Display information about the environment reader table. Shows the process ID, thread ID, and
transaction ID for each active reader slot. The process ID and transaction ID are in decimal, the
thread ID is in hexadecimal. The transaction ID is displayed as "-" if the reader does not
currently have a read transaction open. If -rr is given, check for stale entries in the reader
table and clear them. The reader table will be printed again after the check is performed.
-a Display the status of all of the subdatabases in the environment.
-s subdb
Display the status of a specific subdatabase.