Uvědomuji si, že tento problém již byl vyřešen, ale zajímalo mě, jak by se dal vyřešit pomocí rozšířených událostí SQL Server 2008. Toto je moje první hra s XEvents, takže jsem si jistý, že je co zlepšovat!
Skript pro nastavení testovací databáze
CREATE TABLE [dbo].[TableWithMysteryUpdate](
[Period] [int] NOT NULL,
[ColumnThatWillBeUpdated] [int] NOT NULL
) ON [PRIMARY]
GO
INSERT [dbo].[TableWithMysteryUpdate] ([Period], [ColumnThatWillBeUpdated]) VALUES (1, 20)
INSERT [dbo].[TableWithMysteryUpdate] ([Period], [ColumnThatWillBeUpdated]) VALUES (2, 23)
GO
CREATE TABLE [dbo].[TestTable](
[foo] [int] IDENTITY(1,1) NOT NULL,
[bar] [nchar](10) NOT NULL,
CONSTRAINT [PK_TestTable] PRIMARY KEY CLUSTERED
(
[foo] ASC
)
)
GO
CREATE TRIGGER [dbo].[triggerCausingMysteryUpdate]
ON [dbo].[TestTable]
AFTER INSERT
AS
BEGIN
SET NOCOUNT ON;
UPDATE [dbo].[TableWithMysteryUpdate]
SET [Period] = [Period]+1
END
GO
CREATE PROCEDURE [dbo].[Proc4]
AS
BEGIN
INSERT INTO [dbo].[TestTable]
(
[bar])
VALUES
('Test')
END
GO
CREATE PROCEDURE [dbo].[Proc3]
AS
BEGIN
EXEC dbo.Proc4
END
GO
CREATE PROCEDURE [dbo].[Proc2]
AS
BEGIN
EXEC dbo.Proc3
END
GO
CREATE PROCEDURE [dbo].[Proc1]
AS
BEGIN
EXEC dbo.Proc2
END
Scénář je tedy takový, že TableWithMysteryUpdate
se aktualizuje, ale nejsem si jistý čím. Přidám spouštěč aktualizace, který nedělá nic, aby bylo možné filtrovat tento objekt.
CREATE TRIGGER [dbo].[triggerAfterUpdate]
ON [dbo].[TableWithMysteryUpdate]
AFTER UPDATE
AS
BEGIN
SET NOCOUNT ON;
END
Potom spusťte skript pro vytvoření XEvents Session, spusťte proceduru, která nakonec způsobí, že se zásobník volání spustí, a pak relaci zastavíte.
USE TestDB
DECLARE @DynSql nvarchar(max)
SET @DynSql = '
IF EXISTS(SELECT * FROM sys.server_event_sessions WHERE name=''test_trace'')
DROP EVENT SESSION [test_trace] ON SERVER;
CREATE EVENT SESSION [test_trace]
ON SERVER
ADD EVENT sqlserver.sql_statement_completed(
ACTION (package0.callstack, sqlserver.session_id, sqlserver.sql_text, sqlserver.tsql_stack)
WHERE (object_id = ' + cast(object_id('[dbo].[triggerAfterUpdate]') as varchar(10)) + ')
)
,
ADD EVENT sqlserver.sp_statement_completed(
ACTION (package0.callstack, sqlserver.session_id, sqlserver.sql_text, sqlserver.tsql_stack)
WHERE (object_id = ' + cast(object_id('[dbo].[triggerAfterUpdate]') as varchar(10)) + ')
)
ADD TARGET package0.asynchronous_file_target
(set filename = ''c:\temp\test_trace.xel'' , metadatafile = ''c:\temp\test_trace.xem'')
ALTER EVENT SESSION [test_trace] ON SERVER STATE = START
'
EXEC sp_executesql @DynSql
GO
EXEC dbo.Proc1
GO
ALTER EVENT SESSION [test_trace] ON SERVER STATE = STOP
Data trasování lze číst pomocí
SELECT CONVERT (XML, event_data) AS data
FROM sys.fn_xe_file_target_read_file ('C:\Temp\test_trace*.xel', 'C:\Temp\test_trace*.xem', NULL, NULL)
Část zásobníku volání je
<action name="tsql_stack" package="sqlserver">
<value><frame level='1' handle='0x03000800E8EA0D0612E4EB00A59D00000000000000000000' line='6' offsetStart='228' offsetEnd='264'/>
<frame level='2' handle='0x03000800921155002C81E700A59D00000000000000000000' line='8' offsetStart='258' offsetEnd='398'/>
<frame level='3' handle='0x03000800CB3549012F81E700A59D00000100000000000000' line='5' offsetStart='90' offsetEnd='284'/>
<frame level='4' handle='0x03000800045A3D022F81E700A59D00000100000000000000' line='5' offsetStart='90' offsetEnd='120'/>
<frame level='5' handle='0x030008003D7E31033081E700A59D00000100000000000000' line='5' offsetStart='90' offsetEnd='120'/>
<frame level='6' handle='0x0300080076A225043081E700A59D00000100000000000000' line='5' offsetStart='90' offsetEnd='120'/>
<frame level='7' handle='0x010008002E775203603D9A0D000000000000000000000000' line='2' offsetStart='4' offsetEnd='-1'/></value>
<text />
</action>
Připojování k DMV
WITH CapturedResults AS
( SELECT data.value ( '(/event/@timestamp)[1]', 'DATETIME') AS [TIME],
data.value ( '(/event/data[@name=''cpu'']/value)[1]', 'INT') AS [CPU (ms)],
CONVERT (FLOAT, data.value ('(/event/data[@name=''duration'']/value)[1]', 'BIGINT')) / 1000000 AS [Duration (s)],
data.value ( '(/event/action[@name=''sql_text'']/value)[1]', 'VARCHAR(MAX)') AS [SQL STATEMENT],
CAST(data.value('(/event/action[@name="tsql_stack"]/value)[1]','varchar(MAX)') AS XML) AS [stack_xml]
FROM (SELECT CONVERT (XML, event_data) AS data
FROM sys.fn_xe_file_target_read_file ('C:\Temp\test_trace*.xel', 'C:\Temp\test_trace*.xem', NULL, NULL)
)
entries
)
,
StackData AS
( SELECT frame_xml.value('(./@level)', 'int') AS [frame_level],
frame_xml.value('(./@handle)', 'varchar(MAX)') AS [sql_handle],
frame_xml.value('(./@offsetStart)', 'int') AS [offset_start],
frame_xml.value('(./@offsetEnd)', 'int') AS [offset_end]
FROM CapturedResults CROSS APPLY stack_xml.nodes('//frame') N (frame_xml)
)
SELECT sd.frame_level,
object_name(st.objectid, st.dbid) AS ObjectName,
SUBSTRING(st.text, (sd.offset_start/2)+1, ((
CASE sd.offset_end
WHEN -1
THEN DATALENGTH(st.text)
ELSE sd.offset_end
END - sd.offset_start)/2) + 1) AS statement_text,
qp.query_plan,
qs2.creation_time,
qs2.last_execution_time,
qs2.execution_count
FROM StackData AS sd CROSS APPLY sys.dm_exec_sql_text(CONVERT(VARBINARY(MAX),sd.sql_handle,1)) AS st
LEFT OUTER JOIN sys.dm_exec_query_stats qs2
ON qs2.sql_handle = CONVERT(VARBINARY(MAX),sd.sql_handle,1) OUTER APPLY sys.dm_exec_query_plan(CONVERT(VARBINARY(MAX),qs2.plan_handle,1)) AS qp
dává výsledky (zobrazuje celý zásobník volání tsql)