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MIN_ACTIVE_ROWVERSION (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance

Returns the lowest active rowversion value in the current database. A rowversion value is active if it is used in a transaction that has not yet been committed. For more information, see rowversion (Transact-SQL).

Note

The rowversion data type is also known as timestamp.

Transact-SQL syntax conventions

Syntax

MIN_ACTIVE_ROWVERSION ( ) 

Return Types

Returns a binary(8) value.

Remarks

MIN_ACTIVE_ROWVERSION is a non-deterministic function that returns the lowest active rowversion value in the current database. A new rowversion value is typically generated when an insert or update is performed on a table that contains a column of type rowversion. If there are no active values in the database, MIN_ACTIVE_ROWVERSION returns the same value as @@DBTS + 1.

MIN_ACTIVE_ROWVERSION is useful for scenarios such as data synchronization that use rowversion values to group sets of changes together. If an application uses @@DBTS rather than MIN_ACTIVE_ROWVERSION, it is possible to miss changes that are active when synchronization occurs.

The MIN_ACTIVE_ROWVERSION function is not affected by changes in the transaction isolation levels.

Examples

The following example returns rowversion values by using MIN_ACTIVE_ROWVERSION and @@DBTS. Notice that the values differ when there are no active transactions in the database.

-- Create a table that has a ROWVERSION column in it.  
CREATE TABLE RowVersionTestTable (rv ROWVERSION)  
GO  
  
-- Print the current values for the database.  
PRINT ''  
PRINT 'DBTS'  
PRINT @@DBTS  
PRINT 'MIN_ACTIVE_ROWVERSION'  
PRINT MIN_ACTIVE_ROWVERSION()   
GO  
---------------- Results ----------------  
--DBTS  
--0x00000000000007E2  
--MIN_ACTIVE_ROWVERSION  
--0x00000000000007E3  
  
-- Insert a row.  
INSERT INTO RowVersionTestTable VALUES (DEFAULT)  
SELECT * FROM RowVersionTestTable  
GO  
---------------- Results ----------------  
--rv  
--0x00000000000007E3  
  
-- Print the current values for the database.  
PRINT ''  
PRINT 'DBTS'  
PRINT @@DBTS  
PRINT 'MIN_ACTIVE_ROWVERSION'  
PRINT MIN_ACTIVE_ROWVERSION()  
GO  
---------------- Results ----------------  
--DBTS  
--0x00000000000007E3  
--MIN_ACTIVE_ROWVERSION  
--0x00000000000007E4  
  
-- Insert a new row inside a transaction but do not commit.  
BEGIN TRAN  
INSERT INTO RowVersionTestTable VALUES (DEFAULT)  
SELECT * FROM RowVersionTestTable  
GO  
---------------- Results ----------------  
--rv  
--0x00000000000007E3  
--0x00000000000007E4  
  
-- Print the current values for the database.  
PRINT ''  
PRINT 'DBTS'  
PRINT @@DBTS  
PRINT 'MIN_ACTIVE_ROWVERSION'  
PRINT MIN_ACTIVE_ROWVERSION()   
GO  
---------------- Results ----------------  
--DBTS  
--0x00000000000007E4  
--MIN_ACTIVE_ROWVERSION  
--0x00000000000007E4  
  
-- Commit the transaction.  
COMMIT  
GO  
  
-- Print the current values for the database.  
PRINT ''  
PRINT 'DBTS'  
PRINT @@DBTS  
PRINT 'MIN_ACTIVE_ROWVERSION'  
PRINT MIN_ACTIVE_ROWVERSION()  
GO  
---------------- Results ----------------  
--DBTS  
--0x00000000000007E4  
--MIN_ACTIVE_ROWVERSION  
--0x00000000000007E5  

See Also

@@DBTS (Transact-SQL)
rowversion (Transact-SQL)