postgresql - SQL Find out if a row is being referenced before deleting -

postgresql - SQL Find out if a row is being referenced before deleting -

related question: remove rows not referenced foreign key

but don't want delete yet, , not sure understand accepted reply there.

i have table many rows. of them duplicate (yes going prepare problem generating duplicates). now, before removing duplicates (all duplicate except it's id!), i'd create sure rows not referenced table, in order sure can delete them.

col_1 col_2 col_3 id abc cde fgh 1 abc cde fgh 2 abc cde fgh 3

i want see if can delete row 2 , 3, , see if ids referenced somewhere... possible?

sql postgresql