+ 1

What is a the difference between primary key and unique key

18th Jun 2017, 6:52 AM
Vhonani Makhado
Vhonani Makhado - avatar
2 ответов
+ 1
A primary key, such as an ID has to be unique, how would you find a specific value if there are twenty other keys with the same value (ID)?
19th Jun 2017, 6:04 PM
Jonas Schröter
Jonas Schröter - avatar
+ 1
in primary key null values are not allowed but in unique key null values are allow. it is the one of the difference.☺️
22nd Jun 2017, 1:28 PM
gopal