if you want to screw up, try to use the old OC v.1.5 to 1.5 upgrade way.
And if you want to install a clean and working new v.2.x, INSTALL IT, the regular way,
and afterwards, you may get some assistance, to UPGRADE a COPIED 1.5.x DB !
Everything else is just an attempted shop suicide.
Good Luck
Ernie
My Github OC Site:https://github.com/IP-CAM 5'600 + FREE OC Extensions, on the World's largest private Github OC Repository Archive Site.