Sql统计一个字符串在另一个字符串出现的次数的函数-fnQueryCharCountFromString

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE function [dbo].[fnQueryCharCountFromString](@str varchar(8000),@sub varchar(50))
returns int
as
begin
    declare @pos int,@n int

    select @n=0, @pos=charindex(@sub,@str)

    while(@pos<>0)
    begin
        select @str=right(@str,len(@str)-@pos),@pos=charindex(@sub,@str),@n=@n+1
    end

    return(@n)
end