SQL Server does not remove information restore the ordinal number of an AutoNumber column _mssql

This is often the problem with SQL Server:
After a table has an AutoNumber column, the number of automatic numbers has been accumulated tens of thousands, since testing a lot of data. Now it is time to use this table, the test data has been deleted, the remaining problem is in the entry of new data, numbering will only continue to increase, has been used but deleted numbers can not be used, who knows how to solve this problem?

The truncate command not only clears all the data, but also restores the identity's seed value to its original value.

DBCC CHECKIDENT is more convenient and can specify the value of the seed without deleting the data.
1. TRUNCATE TABLE TableName
2. DBCC checkident (tablename,reseed,1)