sys.fn_cdc_decrement_lsn (Transact-SQL)

SQL Server 2012

Returns the previous log sequence number (LSN) in the sequence based upon the specified LSN.

Topic link icon Transact-SQL Syntax Conventions

sys.fn_cdc_decrement_lsn ( lsn_value )


LSN value. lsn_value is binary(10).


The LSN returned by the function is always less than the specified value, and no LSN values can exist between the two values.

Requires membership in the public database role.

The following example uses sys.fn_cdc_decrement_lsn to set the upper LSN boundary in a query that returns change data rows that have LSN values less than the maximum LSN value.

Use AdventureWorks2012;
DECLARE @from_lsn binary(10), @to_lsn binary(10);
SET @from_lsn = sys.fn_cdc_get_min_lsn('HumanResources_Employee');
SET @to_lsn = sys.fn_cdc_decrement_lsn(sys.fn_cdc_get_max_lsn());
SELECT * FROM cdc.fn_cdc_get_all_changes_HumanResources_Employee( @from_lsn, @to_lsn, 'all');