sql查找最后一个字符匹配

DECLARE @str AS VARCHAR(25)='123_234_567'
select substring(@str,1,LEN(@str)-CHARINDEX('_',reverse(@str)))

输出 123_234

DECLARE @str AS VARCHAR(25)='123_234_567'
select reverse(substring(reverse(@str),1,charindex('_',reverse(@str)) - 1))

输出567