sql数据库多表查询

发布网友发布时间：2022-04-22 21:32

共1个回答

热心网友时间：2022-04-10 01:35

select
  st.StudentNumber,
  st.Name,
  count(*)
from
  student st,
  sbook sk
where
  st.StudentNumber=sk.StudentNumber
and to_char(sk.BorrowingTime,'yyyy')='2008'
group by
  st.StudentNumber,
  st.Name

select
  b.BookNumber,
  b.BookName,
  st.Name,
  sk.BorrowingTime,
  sk.ShouldReturnTime
from
  student st,
  sbook sk,
  book  b
where
  st.StudentNumber=sk.StudentNumber
and sk.BookNumber = b.BookNumber
and month(sk.BorrowingTime) =month(sysdate)

Create view yourViewName as
select
  b.BookNumber,
  b.BookName,
  st.Name,
  sk.BorrowingTime,
  sk.ShouldReturnTime
from
  student st,
  sbook sk,
  book  b
where
  st.StudentNumber=sk.StudentNumber
and sk.BookNumber = b.BookNumber
and month(sk.BorrowingTime) =month(sysdate)

没运行过可能有点问题