Question

尝试将更新后的值作为update触发器内的参数传递给存储过程。如果可能，实现此目的的正确语法是什么？

我一直在寻找一种在调用存储过程时直接使用select的方法（使用execute）。在更新触发器中似乎没有任何其他方式来检索更新的值而不是

select from inserted

如果它返回一个记录集，那么大多数相关的解决方案会以某种方式将select在被调用的存储过程中移动但我无法修改它并且只有一个标量要传递。希望我不必使用局部变量来传递值，这似乎可能但不优雅。感谢。

Answer 1

如果您希望获取在Update期间受影响的列名称和列值并将其保存在数据库的审核表中，您可以尝试以下触发器

ALTER TRIGGER [dbo].[TR_lOCATION_AUDIT] 
ON [dbo].[lOCATION] FOR UPDATE
AS
  DECLARE @bit INT ,
  @field INT ,
  @maxfield INT ,
  @char INT ,
  @fieldname VARCHAR(128) ,
  @TableName VARCHAR(128) ,
  @PKCols VARCHAR(1000) ,
  @sql VARCHAR(2000), 
  @UpdateDate VARCHAR(21) ,
  @UserName VARCHAR(128) ,
  @Type CHAR(1) ,
  @PKSelect VARCHAR(1000)


--You will need to change @TableName to match the table to be audited. 
-- Here we made GUESTS for your example.
SELECT @TableName = 'lOCATION'

-- date and user
SELECT         @UserName = SYSTEM_USER ,
       @UpdateDate = CONVERT(VARCHAR(8), GETDATE(), 112) 
               + ' ' + CONVERT(VARCHAR(12), GETDATE(), 114)

-- Action
IF EXISTS (SELECT * FROM inserted)
       IF EXISTS (SELECT * FROM deleted)
               SELECT @Type = 'U'
       ELSE
               SELECT @Type = 'I'
ELSE
       SELECT @Type = 'D'

-- get list of columns
SELECT * INTO #ins FROM inserted
SELECT * INTO #del FROM deleted

-- Get primary key columns for full outer join
SELECT @PKCols = COALESCE(@PKCols + ' and', ' on') 
               + ' i.' + c.COLUMN_NAME + ' = d.' + c.COLUMN_NAME
       FROM    INFORMATION_SCHEMA.TABLE_CONSTRAINTS pk ,

              INFORMATION_SCHEMA.KEY_COLUMN_USAGE c
       WHERE   pk.TABLE_NAME = @TableName
       AND     CONSTRAINT_TYPE = 'PRIMARY KEY'
       AND     c.TABLE_NAME = pk.TABLE_NAME
       AND     c.CONSTRAINT_NAME = pk.CONSTRAINT_NAME

-- Get primary key select for insert
SELECT @PKSelect = COALESCE(@PKSelect+'+','') 
       + '''<' + COLUMN_NAME 
       + '=''+convert(varchar(100),
coalesce(i.' + COLUMN_NAME +',d.' + COLUMN_NAME + '))+''>''' 
       FROM    INFORMATION_SCHEMA.TABLE_CONSTRAINTS pk ,
               INFORMATION_SCHEMA.KEY_COLUMN_USAGE c
       WHERE   pk.TABLE_NAME = @TableName
       AND     CONSTRAINT_TYPE = 'PRIMARY KEY'
       AND     c.TABLE_NAME = pk.TABLE_NAME
       AND     c.CONSTRAINT_NAME = pk.CONSTRAINT_NAME

IF @PKCols IS NULL
BEGIN
       RAISERROR('no PK on table %s', 16, -1, @TableName)
       RETURN
END

SELECT         @field = 0, 
       @maxfield = MAX(ORDINAL_POSITION) 
       FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = @TableName
WHILE @field < @maxfield
BEGIN
       SELECT @field = MIN(ORDINAL_POSITION) 
               FROM INFORMATION_SCHEMA.COLUMNS 
               WHERE TABLE_NAME = @TableName 
               AND ORDINAL_POSITION > @field
       SELECT @bit = (@field - 1 )% 8 + 1
       SELECT @bit = POWER(2,@bit - 1)
       SELECT @char = ((@field - 1) / 8) + 1
       IF SUBSTRING(COLUMNS_UPDATED(),@char, 1) & @bit > 0
                                       OR @Type IN ('I','D')
       BEGIN
               SELECT @fieldname = COLUMN_NAME 
                       FROM INFORMATION_SCHEMA.COLUMNS 
                       WHERE TABLE_NAME = @TableName 
                       AND ORDINAL_POSITION = @field
               SELECT @sql = '
insert Audit (    Type, 
               TableName, 
               PK, 
               FieldName, 
               OldValue, 
               NewValue, 
               UpdateDate, 
               UserName)
select ''' + @Type + ''',''' 
       + @TableName + ''',' + @PKSelect
       + ',''' + @fieldname + ''''
       + ',convert(varchar(1000),d.' + @fieldname + ')'
       + ',convert(varchar(1000),i.' + @fieldname + ')'
       + ',''' + @UpdateDate + ''''
       + ',''' + @UserName + ''''
       + ' from #ins i full outer join #del d'
       + @PKCols
       + ' where i.' + @fieldname + ' <> d.' + @fieldname 
       + ' or (i.' + @fieldname + ' is null and  d.'
                                + @fieldname
                                + ' is not null)' 
       + ' or (i.' + @fieldname + ' is not null and  d.' 
                                + @fieldname
                                + ' is null)' 
               EXEC (@sql)
  END
END

在update trigger中执行T-SQL存储过程，select from inserted作为参数

1 个答案: