Hi The transaction log file for our production database is growing during the weekly job we run to de-fragment the indexes. The job executes the following steps: Transaction log backup Change database recovery model to "Bulk Logged" De-fragment indexes Change database recovery model to "Full" Transaction log backup The step to de-fragment the indexes is based on the script here: http://technet.microsoft.com/en-us/library/ms188917.aspx under the section: "D. Using sys.dm_db_index_physical_stats in a script to rebuild or reorganize indexes" So the indexes are either re-organised or rebuilt based on the value of "avg_fragmentation_in_percent" from "sys.dm_db_index_physical_stats" The database data file is: 2048 MB in size, and the Transaction log file is also 2048 MB in size, before the index de-fragmentation. When the de-fragmentation ran, the log file grew by 512 MB to 2560 MB. I thought that changing the recovery model, so that index rebuild and reorganisation operations are minimally logged, would stop the transaction log file growth. How can I limit the transaction log growth during the index de-fragmentation step? How can I calculate what size the Transaction log file should be, so that it doesn't grow by itself?