What is SQL Profiler?
SQL Profiler is a graphical tool that permits system administrators to monitor events in an instance of Microsoft SQL Server. You can capture and save data about every event to a file or SQL Server table to analyze later. For instance, you can monitor a production environment to see which stored procedures are hampering performances by executing too slowly.
Use SQL Profiler to monitor only the events in which you are interested. If traces are becoming too large, you can filter them based on the information you require, so that only a subset of the event data is collected. Monitoring too many events adds overhead to the server and the monitoring process and can cause the trace file or trace table to grow very huge, especially when the monitoring process takes place over a long period of time.