Default Trace

sql server trace 是一个轻量级的追踪工具，对追踪数据库的行为很有用，因此，sql server内置一个trace（default trace）。

1，sql server 内置Default Trace，Default Trace的TraceID是1，默认是开启的，可以通过sys.configurations 进行查看

select *
from sys.configurations
where configuration_id=1568

字段 value=1，表示Default Trace是开启的。

2，如果default trace没有开启，可以利用如下语句进行开启，或者关闭等操作。

--开启Default Trace
sp_configure ‘show advanced options‘ , 1 ;
GO
RECONFIGURE;
GO

sp_configure ‘default trace enabled‘ , 1 ;
GO
RECONFIGURE;
GO

--关闭Default Trace
sp_configure ‘default trace enabled‘ , 0 ;
GO
RECONFIGURE;
GO

sp_configure ‘show advanced options‘ , 0 ;
GO
RECONFIGURE;
GO

3，查看Default Trace的trace文件的存放路径，default trace的id是1

select *
from sys.traces
where id=1

Trace status: 0 = stopped ,1 = running

max_size:Maximum trace file size limit in megabytes (MB). This value is null when the trace is a rowset trace.

max_files:Maximum number of rollover files. This value is null if the Max number is not set.

系统默认提供5个跟踪文件，每一个文件的最大size默认是20MB，SQL Server负责维护这5个文件，当实例重启的时候或者到达文件最大值的时候，sql server生成新的文件，将最早的跟踪文件删除，依次滚动（rollover）更新。

4，查看trace 文件的内容

sys.fn_trace_gettable ( ‘filename‘ , number_files )

Be aware that the fn_trace_gettable function will not load rollover files (when this option is specified by using the number_files argument) where the original trace file name ends with an underscore and a numeric value. (This does not apply to the underscore and number that are automatically appended when a file rolls over.) As a workaround, you can rename the trace files to remove the underscores in the original file name. For example, if the original file is named Trace_Oct_5.trc and the rollover file is named Trace_Oct_5_1.trc, you can rename the files to TraceOct5.trc and TraceOct5_1.trc.

filename 能够从sys.traces 中获取。

select *
from sys.fn_trace_gettable(N‘C:\Program Files\Microsoft SQL Server\MSSQL11.MSSQLSERVER\MSSQL\Log\log_4.trc‘,default)

5，查看default trace 追踪的Event 和 EventColumn

fn_trace_geteventinfo ( trace_id )

该函数返回 EventID 和 EventColumnID

select tgei.eventid,tgei.columnid
from sys.fn_trace_geteventinfo(1) tgei

查看default trace 追踪的Event详细信息，包括 Catagory,EventName 和 Column

select categ.name as CategoryName,
    te.trace_event_id as EventID,
    te.name as EventName,
    tc.trace_column_id as EventColumnID,
    tc.name as ColumnName,
    tc.type_name as ColumnType
from sys.fn_trace_geteventinfo(1) as gei
inner join sys.trace_columns tc
    on gei.columnid=tc.trace_column_id
inner join sys.trace_events te
    on gei.eventid=te.trace_event_id
inner join sys.trace_categories categ
    on te.category_id=categ.category_id
order by CategoryName,EventID,EventColumnID

6，查看Event和其Category，Category用于组织Event。在SQL Server 2012中，共有21个Category，180个Event，每个Event属于唯一的一个Category。

select tc.name as CategoryName,
    te.trace_event_id as EventID,
    te.name as EventName
from sys.trace_categories tc
inner join sys.trace_events te
    on tc.category_id=te.category_id
order by CategoryName

7，查看Event的Column，在SQL Server 2012中，共有66个Column，并不是每个Event都能绑定所有66个column，每个Event能够绑定的Column是固定的。
The sys.trace_event_bindings catalog view contains a list of all possible usage combinations of events and columns. For each event listed in the trace_event_id column, all available columns are listed in the trace_column_id column. Not all available columns are populated each time a given event occurs.

select te.trace_event_id as EventID,
    te.name as EventName,
    tc.trace_column_id as EventColumnID,
    tc.name as ColumnName,
    tc.type_name as ColumnType
from sys.trace_event_bindings teb
inner join sys.trace_columns tc
    on teb.trace_column_id=tc.trace_column_id
inner join sys.trace_events te
    on teb.trace_event_id=te.trace_event_id
order by EventID,EventColumnID

参考doc：

Server-wide Configuration Catalog Views (Transact-SQL)

System Trace Functions