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sys.database_files (Transact-SQL)

Contains a row per file of a database as stored in the database itself. This is a per-database view.

Column name

Data type

Description

file_id

int

ID of the file within database.

file_guid

uniqueidentifier

GUID for the file.

NULL = Database was upgraded from an earlier version of SQL Server.

type

tinyint

File type:

0 = Rows (Includes files of full-text catalogs that are upgraded to or created in SQL Server 2008.)

1 = Log

2 = FILESTREAM

3 = Identified for informational purposes only. Not supported. Future compatibility is not guaranteed.

4 = Full-text (Full-text catalogs earlier than SQL Server 2008; full-text catalogs that are upgraded to or created in SQL Server 2008 will report a file type 0.)

type_desc

nvarchar(60)

Description of the file type:

ROWS (Includes files of full-text catalogs that are upgraded to or created in SQL Server 2008.)

LOG

FILESTREAM

FULLTEXT (Full-text catalogs earlier than SQL Server 2008.)

data_space_id

int

Value can be 0 or greater than 0. A value of 0 represents the database log file, and a value greater than 0 represents the ID of the filegroup where this data file is stored.

name

sysname

Logical name of the file in the database.

physical_name

nvarchar(260)

Operating-system file name.

state

tinyint

File state:

0 = ONLINE

1 = RESTORING

2 = RECOVERING

3 = RECOVERY_PENDING

4 = SUSPECT

5 = Identified for informational purposes only. Not supported. Future compatibility is not guaranteed.

6 = OFFLINE

7 = DEFUNCT

state_desc

nvarchar(60)

Description of the file state:

ONLINE

RESTORING

RECOVERING

RECOVERY_PENDING

SUSPECT

OFFLINE

DEFUNCT

For more information, see File States.

size

int

Current size of the file, in 8-KB pages.

0 = Not applicable

For a database snapshot, size reflects the maximum space that the snapshot can ever use for the file.

max_size

int

Maximum file size, in 8-KB pages:

0 = No growth is allowed.

-1 = File will grow until the disk is full.

268435456 = Log file will grow to a maximum size of 2 TB.

NoteNote
Databases that are upgraded with an unlimited log file size will report -1 for the maximum size of the log file.

growth

int

0 = File is fixed size and will not grow.

>0 = File will grow automatically.

If is_percent_growth = 0, growth increment is in units of 8-KB pages, rounded to the nearest 64 KB.

If is_percent_growth = 1, growth increment is expressed as a whole number percentage.

is_media_read_only

bit

1 = File is on read-only media.

0 = File is on read-write media.

is_read_only

bit

1 = File is marked read-only.

0 = File is marked read/write.

is_sparse

bit

1 = File is a sparse file.

0 = File is not a sparse file.

For more information, see Understanding Sparse File Sizes in Database Snapshots.

is_percent_growth

bit

1 = Growth of the file is a percentage.

0 = Absolute growth size in pages.

is_name_reserved

bit

1 = Dropped file name (name or physical_name) is reusable only after the next log backup. When files are dropped from a database, the logical names stay in a reserved state until the next log backup. This column is relevant only under the full recovery model and the bulk-logged recovery model.

create_lsn

numeric(25,0)

Log sequence number (LSN) at which the file was created.

drop_lsn

numeric(25,0)

LSN at which the file was dropped.

0 = The file name is unavailable for reuse.

read_only_lsn

numeric(25,0)

LSN at which the filegroup that contains the file changed from read/write to read-only (most recent change).

read_write_lsn

numeric(25,0)

LSN at which the filegroup that contains the file changed from read-only to read/write (most recent change).

differential_base_lsn

numeric(25,0)

Base for differential backups. Data extents changed after this LSN will be included in a differential backup.

differential_base_guid

uniqueidentifier

Unique identifier of the base backup on which a differential backup will be based.

differential_base_time

datetime

Time corresponding to differential_base_lsn.

redo_start_lsn

numeric(25,0)

LSN at which the next roll forward must start.

Is NULL unless state = RESTORING or state = RECOVERY_PENDING.

redo_start_fork_guid

uniqueidentifier

Unique identifier of the recovery fork. The first_fork_guid of the next log backup restored must match this value. This represents the current state of the file.

redo_target_lsn

numeric(25,0)

LSN at which the online roll forward on this file can stop.

Is NULL unless state = RESTORING or state = RECOVERY_PENDING.

redo_target_fork_guid

uniqueidentifier

The recovery fork on which the file can be recovered. Paired with redo_target_lsn.

backup_lsn

numeric(25,0)

The LSN of the most recent data or differential backup of the file.

Note

When you drop or rebuild large indexes, or drop or truncate large tables, the Database Engine defers the actual page deallocations, and their associated locks, until after the transaction commits. Deferred drop operations do not release allocated space immediately. Therefore, the values returned by sys.database_files immediately after dropping or truncating a large object may not reflect the actual disk space available. For more information about deferred allocations, see Dropping and Rebuilding Large Objects.

Permissions

Requires membership in the public role. For more information, see Metadata Visibility Configuration.