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sys.dm_db_log_space_usage Returns space usage information for the transaction log.
| Column name | Data type | Description |
|---|---|---|
| database_id | smallint | Database ID. |
| total_log_size_in_bytes | bigint | The size of the log |
| used_log_space_in_bytes | bigint | The occupied size of the log |
| used_log_space_in_percent | real | The occupied size of the log as a percent of the total log size |
| log_space_in_bytes_since_last_backup | bigint | The amount of space used since the last log backup Applies to: SQL Server 2014 (12.x) through SQL Server 2019 (15.x), SQL Database. |
how much log file has been filled up and how much is empty :
SELECT (total_log_size_in_bytes) *1.0/1024/1024 AS [Total Log Size in in MB], (used_log_space_in_bytes) *1.0/1024/1024 AS [Used Log Size in MB], used_log_space_in_percent [Used Log Space in %], (total_log_size_in_bytes - used_log_space_in_bytes)*1.0/1024/1024 AS [free log space in MB] , (log_space_in_bytes_since_last_backup) *1.0/1024/1024 [Log Since Last Log Backup in MB] FROM sys.dm_db_log_space_usage;
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