DECLARE @D DECIMAL(18,9)

,@S VARCHAR(20)

,@R VARCHAR(20)

,@Pos SMALLINT

SET @D = 5.1235698

SET @s-2 = CAST(@D AS VARCHAR(20))

SET @r = REVERSE(SUBSTRING(@S, CHARINDEX('.', @s-2) + 1, 20))

SET @Pos = PATINDEX('%[1-9]%' , @r)

IF @Pos = 0

SELECT 0

ELSE

SELECT LEN(SUBSTRING(@R, @Pos, 20)) AS Length