[bind10-dev] Blog comment from BDB developer

[Danny Mayer]

On 7/13/2010 9:14 AM, Shane Kerr wrote:
> Danny,
> 
> On Tue, 2010-07-13 at 07:46 -0400, Danny Mayer wrote:
>> On 7/12/2010 10:45 PM, zhanglikun wrote:
>>> Danny wrote:
>>>> you have no idea how bad that would be from a DB performance point
>>>> of view. You *really* don't want to do this.
>>>
>>>> I've never heard of something like that in Java and I do quite a  
>>>> lot of Java programming with databases these days. I doubt that 
>>>> this is true.
>>>> Databases either find the records requested or not. There's no in 
>>>> between. You are better off getting the resultset and processing 
>>>> the records for what you need.
>>>
>>> BDB have one native flag ' DB_SET_RANGE ' supporting to get records
>>> in between. see the following discussions.
>>>
>>>> Likun,
>>
>> Yes I read that. The implications of this is that you are going to be
>> limiting bind10 to only use BDB since no other DB supports it. That's
>> okay if you are going to be making that as a final decision, but then
>> that needs to be explicitly stated.
> 
> I'm not sure exactly what you mean. SQL provides us this functionality
> today by using '<' operators. Here is how we find the covering NSEC
> record:
> 
>     SELECT name FROM records 
>     WHERE zone_id=?1 AND rdtype = 'NSEC' AND rname < $2 
>     ORDER BY rname DESC LIMIT 1
> 
> (Pardon the SQLite "LIMIT" extension there, but that is pretty common in
> SQL databases, and can be synthesized if necessary in other SQL
> variants.)

That's fine. It's the use of DB_SET_RANGE that I have reservations about.

Danny