This is very common concept that truncate can not be rolled back. I always hear conversation between developer if truncate can be rolled back or not.
If you use TRANSACTIONS in your code, TRUNCATE can be rolled back. If there is no transaction is used and TRUNCATE operation is committed, it can not be retrieved from log file. TRUNCATE is DDL operation and it is not logged in log file.
Update: (Based on comments of Paul Randal) Truncate *IS* a logged operation, it just doesn’t log removing the records, it logs the page deallocations.
Following example demonstrates how during the transaction truncate can be rolled back.
The code to simulate above result is here.
USE tempdb
GO
-- Create Test Table
CREATE TABLE TruncateTest (ID INT)
INSERT INTO TruncateTest (ID)
SELECT 1
UNION ALL
SELECT 2
UNION ALL
SELECT 3
GO
-- Check the data before truncate
SELECT * FROM TruncateTest
GO
-- Begin Transaction
BEGIN TRAN
-- Truncate Table
TRUNCATE TABLE TruncateTest
GO
-- Check the data after truncate
SELECT * FROM TruncateTest
GO
-- Rollback Transaction
ROLLBACK TRAN
GO
-- Check the data after Rollback
SELECT * FROM TruncateTest
GO
-- Clean up
DROP TABLE TruncateTest
GO
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