FILE_IDEX (Transact-SQL)

Returns the file identification (ID) number for the specified logical file name of the data, log, or full-text file in the current database.

Transact-SQL Syntax Conventions

Składnia

FILE_IDEX ( file_name )

Arguments

• file_name
  Is an expression of type sysname that represents the name of the file for which to return the file ID.

Return Types

int

NULL on error

Uwagi

file_name corresponds to the logical file name displayed in the name column in the sys.master_files or sys.database_files catalog views.

FILE_IDEX can be used in a select list, a WHERE clause, or anywhere an expression is allowed. For more information, see Expressions (Transact-SQL).

Examples

A. Retrieving the file id of a specified file

The following example returns the file ID for the AdventureWorks_Data file.

USE AdventureWorks2012;
GO
SELECT FILE_IDEX('AdventureWorks2012_Data')AS 'File ID';
GO

Here is the result set.

File ID 
------- 
1
(1 row(s) affected)

B. Retrieving the file id when the file name is not known

The following example returns the file ID of the AdventureWorks log file by selecting the logical file name from the sys.database_files catalog view where the file type is equal to 1 (log).

USE AdventureWorks2012;
GO
SELECT FILE_IDEX((SELECT TOP(1)name FROM sys.database_files 
WHERE type = 1))AS 'File ID';
GO

Here is the result set.

File ID 
------- 
2

C. Retrieving the file id of a full-text catalog file

The following example returns the file ID of a full-text file by selecting the logical file name from the sys.database_files catalog view where the file type is equal to 4 (full-text). This example will return NULL if a full-text catalog does not exist.

SELECT FILE_IDEX((SELECT name FROM sys.master_files WHERE type = 4))
AS 'File_ID';

Zobacz także

Odwołanie

Metadata Functions (Transact-SQL)

sys.database_files (Transact-SQL)

sys.master_files (Transact-SQL)