Start a Trace
After you have defined a new trace or created a template by using SQL Server Profiler, you can start, pause, or stop capturing data by using the new trace definition or template.
When you start a trace and the defined source is an instance of the SQL Server Database Engine or Analysis Services, SQL Server creates a queue that provides a temporary holding place for captured server events.
When you use SQL Server Profiler to access SQL Trace, a new trace window opens (if one is not already open) when a trace is started, and data is immediately captured.
When you use Transact-SQL system stored procedures to access SQL Trace, you must start a trace every time an instance of SQL Server starts for data to be captured. When a trace has been started, you can modify only the name of the trace.
When working with existing traces, you can view the properties, but you cannot modify the properties. To modify the properties, stop or pause the trace.