new and old trigger code

Question

can someone please explain what is meant by:

:new and :old in trigger code.

Answer 1

the old value is the value before the change and the new value is the value to be changed, so for example, on a update set col1=10, 10 is the new value and the value that is current in the column is the old on.

On a insert, there isnt old value, only new and on a delete there isn't new value, only old