如何使用来自 2 个不同表的打印创建存储过程？

Question

我在数据库中有 3 个表，1 个是瑜伽课，另一个是成员和它们之间的交集，我想创建一个存储过程来打印 指定 类的详细信息以及分配给班级的每个成员的姓名和联系电话。报告输出的格式应与以下内容相同：

YOGA CLASS REPORT:
___________________

Class ID: 1112
Week day:   Monday    [Time: 07:00:00]
Studio Number: 1

No.  Member Name         Contact Number
________________________________________
1    John Doe            +26 83 562 3953

到目前为止我有：

CREATE PROCEDURE sp_Report  
@classID SMALLINT  
AS  
  IF NOT EXISTS(SELECT * FROM class WHERE classID = @classID)      
  BEGIN  
     RAISERROR ('classID does not exist',16,1)  
     RETURN  
  END

  DECLARE @classWeekday VARCHAR(15)  
  DECLARE @classTime TIME  
  DECLARE @classStudioNo TINYINT

  SELECT @classWeekday = class.classWeekday, @classTime = class.classTime, 
         @classStudioNo = class.classStudioNo  
  FROM class  
  WHERE @classID = classID

  PRINT 'YOGA CLASS REPORT'  
  PRINT 'Class code:' +CAST(@classID AS VARCHAR)  
  PRINT 'Week day:' +@classWeekday +'[Time:' + CAST(@classTime AS VARCHAR)+ ']'   
  PRINT 'Studio Number' +CAST(@classStudioNo AS VARCHAR)  

我现在如何打印参加特定课程的所有成员？任何帮助将不胜感激。

Answer 1

这样的事情会给你参加每个班级的人......

SELECT 
     c.MemeberID
     , m.MemberName
     , m.ContactNumber
FROM 
     class c
     INNER JOIN members m ON
         c.MemberID = m.MemberID 
WHERE c.classID = @classID

看着这个Stack Overflow question，我想知道你为什么实际使用PRINT？

Answer 2

您是否尝试过使用光标？

PRINT 'YOGA CLASS REPORT' 

DECLARE cClasses CURSOR FOR
SELECT classWeekday, classTime, classStudioNo  
FROM class  
WHERE classID = @classID

OPEN cClasses
FETCH NEXT FROM cClasses INTO @classWeekday, @classTime, @classStudioNo
WHILE @@FETCH_STATUS = 0
BEGIN

    PRINT 'Class code:' +CAST(@classID AS VARCHAR)  
    PRINT 'Week day:' +@classWeekday +'[Time:' + CAST(@classTime AS VARCHAR)+ ']'   
    PRINT 'Studio Number' +CAST(@classStudioNo AS VARCHAR)

FETCH NEXT FROM cClasses INTO @classWeekday, @classTime, @classStudioNo
END
CLOSE cClasses
DEALLOCATE cClasses

这里有官方文档在 msdn DECLARE CURSOR SQL SERVER

Answer 3

正如其他人所提到的，我很好奇您为什么要为此使用 print，但鉴于这是一个约束，您必须在连接中使用光标。下面是一些示例代码和一个工作示例。

编辑：我只想补充一点，通常在使用 SQL 时，您会希望避免使用游标。 SQL 是一种基于集合的语言，游标是过程性的。因此，虽然我给出了一个使用游标的示例以满足必须打印每个结果的约束，但我不会在任何生产环境中这样做。

declare @class table (classID int, className nvarchar(100))
insert @class values (1,'TSQL'),(2,'SQL Server')
declare @members table (memberID int, memberName nvarchar(100), contactNumber nvarchar(100))
insert @members values (1, 'John Doe', '+26 83 562 3953'), (2, 'Bert Evans','+26 83 562 3954')
declare @classmembers table (classID int, memberID int)
insert @classmembers values (1,1),(1,2)

declare attendees cursor for 
    select rsMembers.memberID, memberName, contactNumber
    from @members rsMembers
    inner join @classmembers rsClassMembers on rsClassMembers.memberID = rsMembers.memberID
    where rsClassMembers.classID = 1
    
open attendees
declare @number int, @name nvarchar(100), @contact nvarchar(100)
fetch next from attendees into @number, @name, @contact
while @@FETCH_STATUS = 0
begin

    print cast(@number as nvarchar(100)) + ' ' + @name + ' ' + @contact
    fetch next from attendees into @number, @name, @contact
    
end
close attendees
deallocate attendees

Working example.