Question

我创建了一个处理更新的触发器，效果很好。但我正在努力研究如何处理插入。

这是我目前的触发器：

CREATE TRIGGER tr_PersonInCareSupportNeeds_History
ON PersonInCareSupportNeeds
FOR UPDATE
AS
BEGIN

       INSERT INTO [dbo].[PersonInCareSupportNeeds_History]
       ([PersonInCareSupportNeedsID], [EventDate], [EventUser], [ChangedColumn], [PreviousValue], [NewValue])

       SELECT i.[PersonInCareSupportNeedsID], GETDATE(), i.[LastUpdateUser], 'StartDate', CAST(d.[StartDate] AS VARCHAR), CAST(i.[StartDate] AS VARCHAR)
       FROM PersonInCareSupportNeeds I INNER JOIN Deleted D
       ON d.PersonInCareSupportNeedsID = I.PersonInCareSupportNeedsID
       WHERE d.[StartDate] <> i.[StartDate]

       UNION
       -- new values
       SELECT i.[PersonInCareSupportNeedsID], GETDATE(), i.[LastUpdateUser], 'EndDate', CAST(d.[EndDate] AS VARCHAR), CAST(i.[EndDate] AS VARCHAR)
       FROM PersonInCareSupportNeeds I INNER JOIN DELETED D
       ON d.PersonInCareSupportNeedsID = I.PersonInCareSupportNeedsID
       WHERE d.[EndDate] <> i.[EndDate]


END

如何更改此项以处理INSERTS。我还会有一个专栏来处理动作类型'Updated'或'Inserted'。

Answer 1

好笑，但我碰巧正在玩这个：

create trigger dbo.Things_Log on dbo.Things after Delete, Insert, Update as

  declare @Now as DateTimeOffset = SysDateTimeOffset();

  -- Determine the action that fired the trigger.
  declare @Action VarChar(6) =
    case
      when exists ( select 42 from inserted ) and exists ( select 42 from deleted ) then 'update'
      when exists ( select 42 from inserted ) then 'insert'
      when exists ( select 42 from deleted ) then 'delete'
      else NULL end;
  if @Action is NULL
    return;

  -- Assign a unique value to group the log rows for this trigger firing.
  declare @TriggerId as Int;
  update TriggerIds
    set @TriggerId = TriggerId += 1;

  -- Log the data.
  if @Action in ( 'delete', 'update' )
    insert into ThingsLog
      select @Action + '-deleted', @TriggerId, @Now, dbo.OriginalLoginName(), ThingId, ThingName
        from deleted;
  if @Action in ( 'insert', 'update' )
    insert into ThingsLog
      select @Action + '-inserted', @TriggerId, @Now, dbo.OriginalLoginName(), ThingId, ThingName
        from inserted;
go
-- Logging triggers should always fire last.
execute sp_settriggerorder @triggername = 'dbo.Things_Log', @order = 'Last', @stmttype = 'DELETE';
execute sp_settriggerorder @triggername = 'dbo.Things_Log', @order = 'Last', @stmttype = 'INSERT';
execute sp_settriggerorder @triggername = 'dbo.Things_Log', @order = 'Last', @stmttype = 'UPDATE';
go

背景信息：

create function [dbo].[OriginalLoginName]()
  returns NVarChar(128)
  as
  begin
  -- Returns the original login used to create the current session: Domain\username or sqlusername.
  --   This function is not affected by impersonation.
  --   Requires granting execute access to [public] and represents a diminutive security hole.
  declare @Result as NVarChar(128);
  select @Result = original_login_name
    from sys.dm_exec_sessions
    where session_id = @@SPID;
  return @Result;
  end;
go

CREATE TABLE [dbo].[Things](
    [ThingId] [int] IDENTITY(1,1) NOT NULL,
    [ThingName] [varchar](16) NOT NULL
) ON [PRIMARY]

CREATE TABLE [dbo].[ThingsLog](
    [ThingsLogId] [int] IDENTITY(1,1) NOT NULL,
    [Action] [varchar](16) NOT NULL,
    [TriggerId] [int] NOT NULL,
    [TriggerTime] [datetimeoffset](7) NOT NULL,
    [OriginalLoginName] [nvarchar](128) NOT NULL,
    [ThingId] [int] NOT NULL,
    [ThingName] [varchar](16) NOT NULL
) ON [PRIMARY]

CREATE TABLE [dbo].[TriggerIds](
    [TriggerId] [int] NULL
) ON [PRIMARY]

GO
insert into dbo.TriggerIds ( TriggerId ) values ( 0 );

记录触发器应配置为最后触发。这可以防止可能随后由其他触发器回滚的日志记录操作。对于奖励积分，可以报告未配置为最后触发的日志记录触发器的查询（假设您具有一致的命名约定，例如TableName_Log，用于触发器）：

select PO.name as TableName, O.name as TriggerName, TE.type_desc,
  case when O.name like PO.name + '_Log%' then 1 else 0 end as LoggingTrigger,
  case when O.name like PO.name + '_Log%' and TE.is_last = 0 then 1 else 0 end as Misconfigured,
  '' as [-], PO.type_desc as TableType, T.is_disabled, TE.is_first, TE.is_last, T.is_instead_of_trigger
  from sys.objects as O inner join
    sys.triggers as T on T.object_id = O.object_id inner join
    sys.objects as PO on PO.object_id = T.parent_id inner join
    sys.trigger_events as TE on TE.object_id = T.object_id
  where
    PO.type = 'U' and -- User table.
    T.parent_class = 1 and -- Object or column trigger.
    T.is_disabled = 0 and -- Is not disabled.
    T.is_instead_of_trigger = 0 -- AFTER, not INSTEAD OF, trigger.
  order by PO.name, O.name, TE.type_desc;

它可以合并到一个存储过程中，以纠正记录触发器的触发顺序。

更新触发器工作但无法执行插入

1 个答案: