Actually I believe the tracker databases are under .cache/tracker/
I am not sure what the stuff under /home/user/.smartsearch/ is, maybe that is cached all over the filesystem?

~ #
~ # ls -la /home/user/.cache/tracker/
total 37156
d---rwx--- 2 metadata metadata 4096 Nov 27 21:40 .
drwxr-xr-x 9 user users 4096 Nov 26 18:11 ..
-rw-r--r-- 1 user metadata 5 Nov 25 13:57 db-locale.txt
-rw-r--r-- 1 user metadata 2 Nov 25 13:57 db-version.txt
-rw-r--r-- 1 user metadata 7 Nov 25 14:01 first-index.txt
-rw-r--r-- 1 user metadata 10 Nov 25 14:01 last-crawl.txt
-rw-r--r-- 1 user metadata 33985536 Nov 29 07:42 meta.db
-rw-r--r-- 1 user metadata 3663840 Nov 29 07:53 meta.db-wal
-rw-r--r-- 1 user metadata 5 Nov 25 14:00 miner-applications-locale.txt
-rw-r--r-- 1 user metadata 356756 Nov 25 13:57 ontologies.gvdb
~ #