问如何将日期从字符串中分离出来？

EN

declare @yourString varchar(100)
set @yourString = 'on 01-15-09 with a factor of 0.8'

select substring(@yourString,
            patindex('%[0-9][0-9]-[0-9][0-9]-[0-9][0-9]%', @yourString),
            8)

select substring(@yourString,
        patindex('%with a%', @yourString) + 7,
        20)

declare @txt varchar(max)
set @txt = 'on 01-15-09 witha factor of 0.8'

select cast(substring(@txt, patindex('% [0-9][1-9]-%', @txt), 9) as date) [date], 
cast(right(@txt, patindex('%_ %', reverse(@txt))) as decimal(9,1)) Factor

date       Factor
---------- ------
2009-01-15 0.8