Question

SQL：

SELECT  [U].[FirstName]
      , [U].[LastName]
      , [U].[Email]
      , [U].[UserId]
      , [AHI].[Id] AS [AdHocId]
      , [R].[AgentId]
      , [R].[RsvpId]
      , [RC].[AgentId] AS [CertAgentId]
      , [RC].[CertId]
FROM    [dbo].[Users] AS U
        LEFT JOIN [dbo].[AdHocIdentity] AS AHI
            ON [AHI].[Email] = [TUI].[Email]
        LEFT JOIN [dbo].[Rsvp] AS R
            ON [R].[AgentId] = [AHI].[Id]
        LEFT JOIN [dbo].[Certificates] AS RC
            ON [RC].[RsvpId] = [R].[RsvpId]
WHERE   [AHI].[Email] IS NOT NULL
        AND [R].[Completed] = 1
        AND ( [AHI].[Email] LIKE '%@%' )
ORDER BY [AHI].[Email]

输出：

    FirstName   LastName    Email                       UserId                                  AdHocId                                 AgentId                                 RsvpId                                  CertAgentId                             CertId
    Babs        Robespiere  babsrobes@yahoo.com         5950B6AB-E2F0-4923-BA45-7AD843D6937F    71283531-90E6-4570-813B-5B1C706030B8    71283531-90E6-4570-813B-5B1C706030B8    03A99511-7FE1-4D8F-B2FB-59E8302FD531    71283531-90E6-4570-813B-5B1C706030B8    FECE9E84-ECE3-4B78-AC2E-A726CCCC8B13
    Babs        Robespiere  babsrobes@yahoo.com         5950B6AB-E2F0-4923-BA45-7AD843D6937F    5950B6AB-E2F0-4923-BA45-7AD843D6937F    5950B6AB-E2F0-4923-BA45-7AD843D6937F    DD29555E-EE06-4724-8FCD-B825AECDCC82    5950B6AB-E2F0-4923-BA45-7AD843D6937F    9E46C992-4CB4-453E-A4D0-BD16587235CA

目标：

我想更新证书（RC）.AgentId（CertAgentId）和Rsvp（r）.AgentId以匹配用户（u）.UserId。它将呈现如下输出：

    FirstName   LastName    Email                       UserId                                  AdHocId                                 AgentId                                 RsvpId                                  CertAgentId                             CertId
    Babs        Robespiere  babsrobes@yahoo.com         5950B6AB-E2F0-4923-BA45-7AD843D6937F    5950B6AB-E2F0-4923-BA45-7AD843D6937F    5950B6AB-E2F0-4923-BA45-7AD843D6937F    03A99511-7FE1-4D8F-B2FB-59E8302FD531    5950B6AB-E2F0-4923-BA45-7AD843D6937F    FECE9E84-ECE3-4B78-AC2E-A726CCCC8B13
    Babs        Robespiere  babsrobes@yahoo.com         5950B6AB-E2F0-4923-BA45-7AD843D6937F    5950B6AB-E2F0-4923-BA45-7AD843D6937F    5950B6AB-E2F0-4923-BA45-7AD843D6937F    DD29555E-EE06-4724-8FCD-B825AECDCC82    5950B6AB-E2F0-4923-BA45-7AD843D6937F    9E46C992-4CB4-453E-A4D0-BD16587235CA

我最初的想法是呻吟，因为我在光标中设想了一个光标，在所有用户的外部循环，在内部循环到所有的Rsvps。

但那会很难看，也很烦人。

是的，这是“一次性”运行以更新新导入的数据 - 因此不是预定的持续运行。

更新答案是：

/* Update RSVPs */
UPDATE  SRR
SET     [AgentId] = [U].[UserId]
FROM    [dbo].[Users] AS U
        LEFT JOIN [dbo].[AdHocIdentity] AS AHI
            ON [AHI].[Email] = [U].[Email]
        LEFT JOIN [dbo].[Rsvp] AS R
            ON [R].[AgentId] = [AHI].[Id]
WHERE   [AHI].[Email] IS NOT NULL
        AND ( [AHI].[Email] LIKE '%@%' )
        AND ([U].[UserId] != [R].[AgentId]);

/* Update Certs */
UPDATE  SRC
SET     [AgentId] = [U].[UserId]
FROM    [dbo].[Users] AS U
        LEFT JOIN [dbo].[AdHocIdentity] AS AHI
            ON [AHI].[Email] = [U].[Email]
        LEFT JOIN [dbo].[Certificates] AS C
            ON [C].[AgentId] = [AHI].[Id]
WHERE   [AHI].[Email] IS NOT NULL
        AND ( [AHI].[Email] LIKE '%@%' )
        AND ([U].[UserId] != [C].[AgentId]);

Answer 1

使用临时表（我通常使用本地表）最好完成这些任务。只需在一个（或多个）临时表中加载所需的数据，然后使用连接执行一个（或多个）更新，然后就完成了。在执行UPDATE之前，您可以首先将UPDATE作为SELECT运行（使用相同的WHERE子句，但将UPDATE更改为SELECT）只是为了确保UPDATE确实能做正确的事情。

Local and global temporary tables in SQL Server

SQL update query using joins

以一对多关系更新子表的最快方法

1 个答案: