Don't Cast Pearls Not Before Swine.

We say The idiom, "don't cast pearls before swine" means that when someone gives something valuable thing is given to those who will do not appreciate it. The idiom "caviar to the general" has the same meaning. In The Japanese have their own version, the idiom "A koban (a coin almost equivalent to $1,000 dollars?) to for the cats' (猫に小判, neko ni koban) is a traditional saying equivalent to the above idioms. Do you have the other idiom an equivalent in your language country?

"cast pearls before swine" comes from the Bible and "caviar to the general" is from Shakespeare.

In Chinese we have, 對牛彈琴 playing the zither in front of a cow.  What's the equivalent in Korean?