database sql, is that using join or all statement? : everyone, i'm new to sql language, can you help me to solve below question.
i have two tables
table1: 
author
1
2
3
table2:
bookstore  author
A             1
A             2
A             3
B             1
B             2

my question is : how can i select distinct bookstore which includes all authors.
so result would be
bookstore
A