what is the .stt file used for in TDengine database ?
under the dataDir some of the file is called .stt like this :
ssn@TDengine:/var/lib/taos/vnode/vnode14$ cd ..
ssn@TDengine:/var/lib/taos/vnode$ ls -ltR | grep -i stt
-rwxrwxrwx 1 root root 4096 Jan 11 10:19 v18f1736ver22.stt
-rwxrwxrwx 1 root root 4096 Jan 11 10:19 v19f1736ver16.stt
-rwxrwxrwx 1 root root 4096 Jan 10 20:00 v16f1736ver18.stt
-rwxrwxrwx 1 root root 4096 Jan 10 20:01 v17f1736ver27.stt
may I know what is it for ?
a specific description for this file ,what is it used ,does it impact the database performance,etc.