select distinct S.customer_name from depositor as S where not exists ( (select branch_name from branch where branch_city = 'Brooklyn') except (select R.branch_name from depositor as T, account as R where T.account_number = R.account_number and S.customer_name = T.customer_name ))

这是一个SQL查询语句，其目的是查询在布鲁克林市没有开户的所有客户姓名。

具体解释如下：

1. `select distinct S.customer_name`：选择不同的客户姓名，以避免重复。

2. `from depositor as S`：从“存款人”表中选择数据，并将其别名为“S”。

3. `where not exists`：使用“not exists”关键字执行否定的存在性检查。

4. `( (select branch_name from branch where branch_city = 'Brooklyn') except (select R.branch_name from depositor as T, account as R where T.account_number = R.account_number and S.customer_name = T.customer_name ))`：在布鲁克林市开户的所有分行名称与S客户的分行名称进行比较，如果S客户未在任何一个分行开户，则该记录将被选择。

需要注意的是，这个查询语句的具体实现方式可能因数据库系统的不同而有所不同。

相关问题

select distinct customer_name from borrower, loan where borrower.loan_number = loan.loan_number and branch_name = 'Perryridge' and (branch_name, customer_name ) in( select branch_name, customer_name from depositor, account where depositor.account_number = account.account_number )

这是一个 SQL 查询语句，目的是查找在 Perryridge 分行有存款账户的所有客户姓名。具体解释如下：

首先，使用 inner join 连接 borrower 表和 loan 表，以获取所有在 Perryridge 分行有贷款的客户信息。

然后，在 inner join 的结果集上再次使用 inner join 连接 depositor 表和 account 表，以获取所有在 Perryridge 分行有存款账户的客户信息。

最后，使用 select distinct 语句去重并只返回客户姓名。

SELECT DISTINCT s.student_num, s.student_name, '计算机学院' AS college_name, c.class_name, FROM student_info s JOIN classes c ON s.college_id = c.college_id JOIN volunteer_time_table_item t ON s.student_num = t.student_num JOIN volunteer_time_table vtt ON vtt.id = t.volunteer_time_table_id WHERE c.college_id = 1 AND s.level = 2021 AND t.deleted = 0 AND s.deleted = 0 AND vtt.deleted = 0 AND c.deleted = 0 ORDER BY t.volunteer_time_value DESC LIMIT 5;哪里有问题

在SELECT语句中，'计算机学院' AS college_name后面有一个逗号，应该将逗号删除，修改后的语句如下：

SELECT DISTINCT s.student_num, s.student_name, '计算机学院' AS college_name, c.class_name FROM student_info s JOIN classes c ON s.college_id = c.college_id JOIN volunteer_time_table_item t ON s.student_num = t.student_num JOIN volunteer_time_table vtt ON vtt.id = t.volunteer_time_table_id WHERE c.college_id = 1 AND s.level = 2021 AND t.deleted = 0 AND s.deleted = 0 AND vtt.deleted = 0 AND c.deleted = 0 ORDER BY t.volunteer_time_value DESC LIMIT 5;