Question

例如，在数据库＆＃34;图书馆＆＃34;中，我希望在名为＆＃34; Sharpstown＆＃的分支中获取图书标题，借款人的姓名和地址。 34;截止日期是今天？

这就是我做select语句的方法 -

SELECT BOOK.Title,BORROWER.Name, BORROWER.Address
FROM BORROWER,BOOK,LIBRARY_BRANCH,BOOK_LOANS
WHERE BOOK.BookID = BOOK_LOANS.BookID AND
      LIBRARY_BRANCH.BranchID = BOOK_LOANS.BranchID AND 
      BOOK_LOANS.CardNo = BORROWER.CardNo AND
      LIBRARY_BRANCH.BranchName = 'Sharpstown' AND 
      BOOK_LOANS.DueDate = now() -- This is where I want to compare the dates

错误是：

＆＃39;现在＆＃39;不是公认的内置函数名称。

Answer 1

对于SQL Server，请使用getDate()而不是now()。根据{{1}}的数据类型，您可能还有其他问题，因此您可能需要BOOK_LOANS.DueDate：

CAST

＆＃34; ... and CAST(BOOK_LOANS.DueDate as date) = CAST(getDate() as date)＆＃34; SQL Server中的类型具有一天的粒度/精度。默认情况下，date会返回值＆＃34; getDate()＆＃34; type，其粒度/精度为毫秒。

Answer 2

您无法在SQL Server中使用NOW。在SQL Server中，我们有GETDATE()

SELECT BOOK.Title,BORROWER.Name, BORROWER.Address
FROM BORROWER,BOOK,LIBRARY_BRANCH,BOOK_LOANS
WHERE BOOK.BookID = BOOK_LOANS.BookID 
  AND LIBRARY_BRANCH.BranchID = BOOK_LOANS.BranchID 
  AND BOOK_LOANS.CardNo = BORROWER.CardNo 
  AND LIBRARY_BRANCH.BranchName = 'Sharpstown' 
  AND BOOK_LOANS.DueDate = CONVERT(DATE, CAST(GETDATE() AS VARCHAR(12)), 105)

如何在SQL Server中使用系统日期或当前日期

2 个答案: