Extract rpm package content without installing

# create directory in home
mkdir ~/zabbix-proxy-sqlite3

# navigate to dir
cd ~/zabbix-proxy-sqlite3

# download package
curl -o zabbix-proxy-sqlite3.rpm http://repo.zabbix.com/zabbix/4.0/rhel/7/x86_64/zabbix-proxy-sqlite3-4.0.5-1.el7.x86_64.rpm

# extract
rpm2cpio zabbix-proxy-sqlite3.rpm | cpio -idmv

Backup original service:

cp /usr/lib/systemd/system/zabbix-proxy.service ~

Set to service to start with sqlite3 binary:

sed -i "s/^ExecStart.*/ExecStart=\/usr\/sbin\/zabbix_proxy_sqlite3 -c \$CONFFILE/" /usr/lib/systemd/system/zabbix-proxy.service

Set back to original:

sed -i "s/^ExecStart.*/ExecStart=\/usr\/sbin\/zabbix_proxy -c \$CONFFILE/" /usr/lib/systemd/system/zabbix-proxy.service

Check current situation:

cat /usr/lib/systemd/system/zabbix-proxy.service

Backup proxy conf:

cp /etc/zabbix/zabbix_proxy.conf ~

Check current database situation:

grep ^DB /etc/zabbix/zabbix_proxy.conf

Set path to database:

sed -i "s/^DBName=.*$/DBName=\/dev\/shm\/zbx.sqlite3.db/" /etc/zabbix/zabbix_proxy.conf

Replace database port:

sed -i "s/^DBPort=.*$/DBPort=3306/" /etc/zabbix/zabbix_proxy.conf