When you are using Sql Server Management studio, some times you might forget to save a query you have just created and accidentally close the query window. In that case you can use the Sql Server cache to to the history of queries.

 

SELECT d.plan_handle ,

d.sql_handle ,

e.text,

d.last_execution_time,

dbname = db_name(e.dbid)

FROM sys.dm_exec_query_stats d

CROSS APPLY sys.dm_exec_sql_text(d.plan_handle) AS e 

 

The data in sys.dm_exec_query_stats is reset every time SQL Server is restarted Or the plan cache was flushed due to memory pressure.