Issue

I got the following error message when I delete tables and then start data import.

The transaction log for database 'DATABASENAME' is full due to 'LOG_BACKUP'.

Check log file size

SELECT file_id, name, type_desc, physical_name, size, max_size  
FROM sys.database_files; 

Output

Size number is in 8-KB page. Therefore, for sizes of:

• 2,355,384, it is equal to 2,355,384*8 = 18,843,072 KB = 18 GB
• -1, it means to fill up to the full capacity of your hard drive
• 49,656, it is equal to 49,656*8 = 397,248 KB = 397 MB
• 1,280,000, it is equal to 1,280,000*8 = 10,240,000 KB = 10 GB

Solution

Flush the log file.

USE DATABASENAME
 
-- Truncate the log by changing the database recovery model to SIMPLE.
ALTER DATABASE DATABASENAME
SET RECOVERY SIMPLE
GO
 
-- Shrink the truncated log file to 1 MB.  
DBCC SHRINKFILE('DATABASENAME_log', 1)
GO
 
-- Reset the database recovery model.  
ALTER DATABASE DATABASENAME
SET RECOVERY FULL
GO