for running tests for postgresql or mysql create environment variable CLTEST_DBURI
without CLTEST_DBURI testcase run only on sqlite
for example
/opt/alt/python37/bin/nosetests -v test_lveinfolib.py
run tests for postgresql only
export CLTEST_DBURI=postgresql://postgres:sW%3EKMpW%24@127.0.0.1; /opt/alt/python37/bin/nosetests -a postgresql -v; ./clear_db.py
run tests for MySQL only
export CLTEST_DBURI=mysql://root:Jzb%2477%21JkS%7C%7D%3Bi%23%29b@localhost; /opt/alt/python37/bin/nosetests -a mysql -v; ./clear_db.py

"./clear_db.py" using for clear temporary created databases for unittests
DO NOT DO THIS ON A LIVE SERVER!!
for faster create temporary database on postgresql and faster run unittests
change in postgresql.conf (for cPanel /var/lib/pgsql/data/postgresql.conf) "fsync" to "off"
fsync = off


Another way to run tests (based on lve-stats-test package):
lve-stats-tests -dt=sqlite -dn=/var/lve/test_lvestats2.sqlite
lve-stats-tests -dt=postgresql -dl=postgres -dp="QtDoMh45bG7" -dh=127.0.0.1
lve-stats-tests -dt=mysql -dl=root -dp='|}oH:421q1oN!Oo|' -dh=127.0.0.1