In this post the focus is on identifying when tables in a database were last updated. Although this can be acheived by adding a column to tables in a database with default constraint getdate() that updates the column value with the new date and time, it cannot be used in situations with already exisiting tables where changing the DDL is not intended. In such cases, the following script can be used:
SELECT OBJECT_NAME(OBJECT_ID) AS TableName, max(last_user_update) FROM sys.dm_db_index_usage_stats WHERE database_id = DB_ID( 'your databasename') and last_user_update is not null group by OBJECT_NAME(OBJECT_ID)
Hope it helps.