Postgresql complex insert into

gistfile1.txt

Consider the model:

car
|id|code|Model name|
|1|100|Deluxe|
|10|100|Deluxe improved|

color
|id|Name|
|2|Red|

car_colors
|id|car_id|color_id|
|3|1|2|


The deluxe car was added, and afterwards the "deluxe improved" model was inserted. It's a new version of the same car (same code). Unfortunately, John Doe forgot to update the car_colors table, so now you want to update that table by inserting the same colors for "Deluxe improved" as there existed for the "Deluxe" model.

The PSEUDO-CODE (non-sql) should be something like:
all_cars_and_colors = select * from car left outer join car_colors

for each(this_car:all_cars_and_colors){

	if(all_cars_and_colors.color_id does not exist){
		car_colors_to_copy = select * from car inner join car_colors where car.code=this_car.code

		for each(color_to_copy: car_colors_to_copy){
			insert into car_colors(id,car_id,color_id) VALUES (nextval('id_sequence') ,this_car.id,color_to_copy.color_id)
		}

	}
}