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sys.fn_cdc_decrement_lsn (Transact-SQL)

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

Topic link iconTransact-SQL Syntax Conventions

Syntax

sys.fn_cdc_decrement_lsn (lsn_value)

Arguments

  • lsn_value
    LSN value. lsn_value is binary(10).

Return Type

binary(10)

Remarks

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

Permissions

Requires membership in the public database role.

Examples

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 AdventureWorks2008R2;
GO
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'); 
GO