Pretty simple question here... How does the light spell affect vampires? Does it hurt them like sunlight? The spell descrip says "normal light". Does that mean it's a "sun"light spell?
I as far as I know it doesn't only spells that call out doing extra damage to creatures with sun venerability
One example is the spell sun beam
"In addition, the beam results in the destruction of any undead creature specifically harmed by bright light if it fails its save."
No. Also sunlight is bright light at the very least, so ligth is just as harmful to vampires as a lightbulb. Which means unless you hit them over the head with it, not at all.
Sunlight is Bright light. A light spell cannot bring light levels to higher than normal light (per the light spell description) but a stronger spell like Daylight could harm vampires. The light levels are bright light > normal light > dim light > darkness > super darkness. Check out the Vision & Light section in the Additional Rules chapter of the Core rules.
So to answer your question, the Light Spell (level 0 spell) doesn't harm a vampire at all. It's like light from a fire or candle