sql server function charindex at n position

Charindex at n position

To find the charindex of an expression “_” in n position say 3^rd occurancein a given word 'xx_xxx_xx_xx'

Result : 10

SELECT dbo.fn_charIndex('_',3,' xx_xxx_xx_xx')

CREATE FUNCTION [dbo].[fn_charIndex](@Expression varchar(256),@nPos int,@Word varchar(2000)) returns int as begin Declare @ret int,@strt int, @strLen int set @ret = 0 set @strt = 0 while not @strt = @npos begin select @ret = charindex(@Expression,@Word,@ret+1) set @strt = @strt +1 IF @ret = 0 Break ELSE Continue end return @ret end