如何在更新另一张表时创建SQL触发器以更新一张表上的日期字段

Question

我想在数据库中创建一个触发器，该触发器应在表'Valve'更新时运行。

作为触发条件的一部分，必须发生以下情况：

1. 应根据Valve表的模式[PnPID，位置X / Y / Z，LineNumberTag，标签，规格]创建或更新ME表
2. 来自现有表Valve的所有信息，将被复制/更新到表ME

这些更改应根据源Valve在表ME中自动发生，而无需任何手动干预。

请帮助我创建这样的触发器？我是SQL新手。

在我的表ME.Valve上，我想添加其他列，这些列具有新的信息，这些信息我不想出现在Valve表中（不要破坏它）。我在现有的表Valve上附上图片。 因此，我想要从表SQL_P3D_Test_ME中的表“ Valve_PNP”复制，例如仅复制“ LineNumberTag”，“ Tag”列，但是当表“ Valve_PNP”列的“ LineNumberTag”，“ Tag”值更改时，要进行更改并自动进入我的表格SQL_P3D_Test_ME。 然后在我的表格SQL_P3D_Test_ME中添加新列，例如在每个阀门前面的行中手动插入信息。 有可能吗？

这就是我想要的，在表“ dbo.Source Tabel”中，您只有一行，其中包含“ TextColumn”，“ ValueColumn”等列中的信息。首先，此信息将复制到表[me]中。 [目标表]，但是当信息输入到表“ dbo.Source Tabel”中时，例如“ TextColumn”列中的信息从“测试插入和数据不变地更新”中用“ Marius”更改为表[me]中的更新。 [表格]仅此信息，而不添加新行。对于每一列，依此类推。

我使用Microsoft SQL Server Management Studio

Answer 1

我建议将触发器添加到“ Valve”表中，该表包含对“ ME.Valve”表的更新。让我知道是否应该编写语法示例。

这是我的解决方案的一个例子。

USE [SpecifyYourDatabaseHere]

CREATE TABLE dbo.SourceTable
    (
    SourcePrimaryKeyID INT IDENTITY PRIMARY KEY,
    TextColumn VARCHAR(2048),
    ValueColumn DECIMAL(18,3),
    NumberColumn INT
    )

CREATE TABLE [me].[DestinationTable]
    (
    DestinationPrimaryKeyID INT IDENTITY PRIMARY KEY,
    SourcePrimaryKeyID INT,
    TextColumn VARCHAR(2048),
    ValueColumn DECIMAL(18,3),
    NumberColumn INT,
    ActionType VARCHAR(100),
    CreatedDate AS GETDATE(), -- Default to current date
    CreatedDatabaseUser AS SUSER_SNAME()
    )

GO

-- You will need an insert, update and delete trigger.

-- INSERT TRIGGER

-- This trigger will insert any new records into the destination table.
CREATE TRIGGER [dbo].[SourceTable_Insert]
ON [dbo].[SourceTable]
FOR INSERT

AS 

INSERT INTO [me].[DestinationTable] 
    (
    SourcePrimaryKeyID,
    TextColumn,
    ValueColumn,
    NumberColumn,
    ActionType
    )
SELECT  INSERTED.SourcePrimaryKeyID,
        INSERTED.TextColumn,
        INSERTED.ValueColumn,
        INSERTED.NumberColumn,
        'Insert' AS ActionType
FROM    INSERTED

GO

-- UPDATE TRIGGER

-- Conditional Update Trigger : This trigger will only insert data in destination of any of the values in the data columns has changed (Saves space).
CREATE TRIGGER [dbo].[SourceTable_Update]
ON [dbo].[SourceTable]
FOR UPDATE

AS 

INSERT INTO [me].[DestinationTable] 
    (
    SourcePrimaryKeyID,
    TextColumn,
    ValueColumn,
    NumberColumn,
    ActionType
    )
SELECT  INSERTED.SourcePrimaryKeyID,
        INSERTED.TextColumn,
        INSERTED.ValueColumn,
        INSERTED.NumberColumn,
        'Update' AS ActionType
FROM    INSERTED
        INNER JOIN
            (
            SELECT  SourcePrimaryKeyID,TextColumn,ValueColumn,NumberColumn
            FROM    [me].[DestinationTable]
                    INNER JOIN
                        (
                        SELECT  MAX(DestinationPrimaryKeyID) MaxDestinationPrimaryKeyID,
                                COUNT(1) DestinationRecordCount
                        FROM    [me].[DestinationTable]
                                INNER JOIN
                                    INSERTED ON
                                        [me].[DestinationTable].SourcePrimaryKeyID = INSERTED.SourcePrimaryKeyID
                        GROUP BY
                            [me].[DestinationTable].SourcePrimaryKeyID
                        ) MaxDestinationPrimaryKey ON
                        MaxDestinationPrimaryKey.MaxDestinationPrimaryKeyID = [me].[DestinationTable].DestinationPrimaryKeyID
            ) DestinationData ON
                DestinationData.SourcePrimaryKeyID = INSERTED.SourcePrimaryKeyID
                AND (
                        ISNULL(DestinationData.TextColumn,'') != ISNULL(INSERTED.TextColumn,'') OR 
                        ISNULL(DestinationData.ValueColumn,0) != ISNULL(INSERTED.ValueColumn,0) OR 
                        ISNULL(DestinationData.NumberColumn,0) != ISNULL(INSERTED.NumberColumn,0)
                    )

GO

-- DELETE TRIGGER

-- This trigger will insert any deleted records into the destination table.

CREATE TRIGGER [dbo].[SourceTable_Delete]
ON [dbo].[SourceTable]
FOR DELETE

AS 

INSERT INTO [me].[DestinationTable] 
    (
    SourcePrimaryKeyID,
    TextColumn,
    ValueColumn,
    NumberColumn,
    ActionType
    )
SELECT  INSERTED.SourcePrimaryKeyID,
        INSERTED.TextColumn,
        INSERTED.ValueColumn,
        INSERTED.NumberColumn,
        'Delete' AS ActionType
FROM    INSERTED

GO

-- Test the code..

-- Insert trigger 
INSERT  [dbo].[SourceTable]
SELECT  'test insert and update with no data change',
        123.456,
        1

INSERT  [dbo].[SourceTable]
SELECT  'test insert and update with data changed',
        123.456,
        1

INSERT  [dbo].[SourceTable]
SELECT  'test delete',
        123.456,
        1

-- Update trigger test 1 - no data changed (Must not add record in destination)
UPDATE  [dbo].[SourceTable]
SET     NumberColumn = 1
WHERE   SourcePrimaryKeyID = 1

-- Update trigger test 2 - Data changed (Must add record in destination)
UPDATE  [dbo].[SourceTable]
SET     NumberColumn = NumberColumn + 1
WHERE   SourcePrimaryKeyID = 2

-- Deleted trigger test
DELETE FROM [dbo].[SourceTable]
WHERE   SourcePrimaryKeyID = 3

SELECT  *
FROM    dbo.SourceTable

SELECT  *
FROM    me.DestinationTable
ORDER BY
        SourcePrimaryKeyID,
        DestinationPrimaryKeyID