sony rx100 or lumix dmc lx7

LX7 is certainly not a bad camera, but its biggest flaw is the small sensor. Compared to RX100, it's quite small as you can see here:

panasonic_lumix-dmc-lx7-vs-sony_cybershot-dsc-rx100 at www.digicamdb.com

If you're planning to work in low light conditions, then I recommend RX100.

i would say sony rx100 because of its light sensitivity and CMOS large sensor that provides high quality photos and other specs

I would recommend Sony RX100 for all of your priorities. For low-light portraits and low-light photography, both are good choices but Sony gets ahead with its much bigger sensor and bigger resolution. 

For travelling purposes these two have a limited zoom, but Sony RX100 makes it up by its good resolution (you can crop the photos better without significant loss in quality). LX7 has a wider angle lens, though, but both cameras have good panorama options for landscape photography.

Sony is a little more expensive but it is well worth it. The bottom line, Panasonic LX7 is a very good compact, but Sony RX100 is a brilliant one.