Common string operations in SQL Server 2008

1. Find the last occurence of a character within a string in sql server 2008

DECLARE @StringA varchar(100), @pos int, @FindChar char(1)=','
SET @stringA = 'DirectoryA,'

SET @pos = LEN(@StringA) - CHARINDEX(',',REVERSE(@StringA))
SELECT @pos

2. How to remove special char from a string in sql server 2008

select replace(@stringA,',','')

3. How to remove last occurence  from a string in sql server 2008

Select SUBSTRING (@stringA, 1, len(@stringA)-1)

4. How to remove last occurence of comma from a string in sql server 2008

select case

when right(rtrim(@stringA),1) = ',' then substring(rtrim(@stringA),1,len(rtrim(@stringA))-1)

else @stringA END