Fix bug: DB_query_builder do not add parenthesis for cached group_by
Fix bug: DB_query_builder do not add parenthesis for cached group_by

kala725/CodeIgniter-with-React,openset/ci,poing/CodeIgniter,kala725/CodeIgniter-with-React,jim-parry/CodeIgniter,ster/CodeIgniter,ipabz/CodeIgniter,asmdigital/CodeIgniter,Tpojka/CodeIgniter,Calico90/CodeIgniter,gastongr/CodeIgniter,Calico90/CodeIgniter,kala725/CodeIgniter-with-React,andersonunsonst/CodeIgniter,tianhe1986/CodeIgniter,Tpojka/CodeIgniter,gastongr/CodeIgniter,openset/ci,ET-NiK/CodeIgniter,ster/CodeIgniter,Tpojka/CodeIgniter,madwings/InsaneDB,ganiutomo/CodeIgniter,kala725/CodeIgniter-with-React,andersonunsonst/CodeIgniter,ivantcholakov/CodeIgniter,madwings/InsaneDB,DiederikLascaris/CodeIgniter,butane/CodeIgniter,Calico90/CodeIgniter,DiederikLascaris/CodeIgniter,dhayalram123/CodeIgniter,ivantcholakov/CodeIgniter,ytetsuro/CodeIgniter,b1tc0re/CodeIgniter,poing/CodeIgniter,asmdigital/CodeIgniter,ganiutomo/CodeIgniter,ivantcholakov/CodeIgniter,ipabz/CodeIgniter,skullJ/CodeIgniter,ganiutomo/CodeIgniter,gastongr/CodeIgniter,smallp/CodeIgniter,butane/CodeIgniter,tianhe1986/CodeIgniter,bcit-ci/CodeIgniter,ytetsuro/CodeIgniter,ipabz/CodeIgniter,ytetsuro/CodeIgniter,Tpojka/CodeIgniter,skullJ/CodeIgniter,gastongr/CodeIgniter,b1tc0re/CodeIgniter,jim-parry/CodeIgniter,bcit-ci/CodeIgniter,jim-parry/CodeIgniter,tianhe1986/CodeIgniter,ipabz/CodeIgniter,poing/CodeIgniter,smallp/CodeIgniter,bcit-ci/CodeIgniter,openset/ci,openset/ci,kamaslau/BasicCodeIgniter,openset/ci,butane/CodeIgniter,b1tc0re/CodeIgniter,bcit-ci/CodeIgniter,DiederikLascaris/CodeIgniter,Calico90/CodeIgniter,dhayalram123/CodeIgniter,ytetsuro/CodeIgniter,DiederikLascaris/CodeIgniter,kala725/CodeIgniter-with-React,ster/CodeIgniter,kamaslau/BasicCodeIgniter,poing/CodeIgniter,ivantcholakov/CodeIgniter,butane/CodeIgniter,jim-parry/CodeIgniter,ganiutomo/CodeIgniter,jim-parry/CodeIgniter,gastongr/CodeIgniter,ytetsuro/CodeIgniter,ster/CodeIgniter,tianhe1986/CodeIgniter,b1tc0re/CodeIgniter,ganiutomo/CodeIgniter,asmdigital/CodeIgniter,asmdigital/CodeIgniter,DiederikLascaris/CodeIgniter,tianhe1986/CodeIgniter,ivantcholakov/CodeIgniter,ipabz/CodeIgniter,dhayalram123/CodeIgniter,b1tc0re/CodeIgniter,andersonunsonst/CodeIgniter,kamaslau/BasicCodeIgniter,madwings/InsaneDB,Calico90/CodeIgniter,ET-NiK/CodeIgniter,asmdigital/CodeIgniter,ET-NiK/CodeIgniter,ster/CodeIgniter,andersonunsonst/CodeIgniter,madwings/InsaneDB,kamaslau/BasicCodeIgniter,madwings/InsaneDB,dhayalram123/CodeIgniter,Tpojka/CodeIgniter,bcit-ci/CodeIgniter,butane/CodeIgniter,poing/CodeIgniter,ET-NiK/CodeIgniter,ET-NiK/CodeIgniter,skullJ/CodeIgniter