Two Useful Hierarchy Functions

SQLServerCentral is supported by Red Gate Software Ltd.

Popular Topics

Home

Members

Calendar

Who's On

Home » Article Discussions » Article Discussions by Author » Discuss content posted by John Cawley III » Two Useful Hierarchy Functions

16 posts, Page 2 of 2

««1 2

Two Useful Hierarchy Functions

Rate Topic

Display Mode

Topic Options

Author

Message

John Cawley III

Posted Thursday, May 22, 2008 12:16 PM

Forum Newbie

Group: General Forum Members
Last Login: Friday, April 12, 2013 10:51 AM
Points: 2, Visits: 26

I apologize, Omama -- I was just using that as an example if you had a Salaries table to subtotal against. Though not included in the article, we can create a quick simple table that will work:

create table salaries(
emp_id int not null,
salary money,
fica money
)
GO
insert into salaries values( 1, 110000, 11000 )
insert into salaries values( 2, 100000, 10000 )
insert into salaries values( 3, 70000, 7000 )
insert into salaries values( 4, 90000, 9000 )
insert into salaries values( 5, 95000, 9500 )
insert into salaries values( 6, 60000, 6000 )
insert into salaries values( 7, 75000, 75000 )
insert into salaries values( 8, 50000, 50000 )
insert into salaries values( 9, 55000, 55000 )
insert into salaries values( 10, 60000, 6000 )
GO

select
sum( s.salary ) departmental_salary_total,
sum( s.fica ) as departmental_fica_total
from subordinates( 2007, 2 ) base
left join salaries s
on s.emp_id = node_id

Post #505393

Tod Conover

Posted Friday, May 30, 2008 5:54 PM

Forum Newbie

Group: General Forum Members
Last Login: Friday, June 05, 2009 12:09 PM
Points: 2, Visits: 19

For reporting purposes we would generally want to sort all the nodes within one parent by node name. Below is an extension to the subordinates function that returns a field suitable for this purpose. The added field is called "node_sort" so your query might look like this...

select * from subordinates(2007,1) order by node_sort, node_name

----- create Subordinates function using CTE with added sort field

if object_id( 'subordinates', 'IF' ) is not null drop function subordinates
GO
create function subordinates( @year int, @node_id int ) returns table as return
with subnodes( distance, year, node_id, parent_node, node_name, node_seq, node_sort) as
(
select 0, @year, h.node_id, h.parent_node, h.node_name,
convert( varchar(99), ltrim(str(h.node_id))) as node_seq,
convert( varchar(99), '')
from hierarchy h where h.node_id = @node_id and h.year = @year
union all
select distance+1, @year, h.node_id, h.parent_node, h.node_name,
convert( varchar(99), sn.node_seq + '.' + ltrim(str(h.node_id))),
convert( varchar(99), sn.node_sort + '.' + right('00000' + cast(isnull(h.parent_node,'0') as varchar(5)), 5) )
from hierarchy h inner join subnodes sn on h.year = @year and h.parent_node = sn.node_id
)
select distance, year, node_id, parent_node, node_name, node_seq, node_sort from subnodes
GO

Post #509428

José Luis R.

Posted Thursday, October 02, 2008 6:22 AM

Forum Newbie

Group: General Forum Members
Last Login: Thursday, October 02, 2008 8:46 AM
Points: 1, Visits: 6

EXCELENTE TU SUGERENCIA, TOD!!! REALMENTE EXCELENTE!!!

Enhorabuena Tod!

Post #579598

Jack-408956

Posted Tuesday, August 03, 2010 2:15 AM

Forum Newbie

Group: General Forum Members
Last Login: Tuesday, August 03, 2010 2:05 AM
Points: 4, Visits: 3

None of this "with" stuff is working for us on MSSQL 2000...

Server: Msg 156, Level 15, State 1, Procedure subordinates, Line 2
Incorrect syntax near the keyword 'with'.

Is it a feature of MSSQL 2005 only?

Post #962638

Jeff Moden

Posted Tuesday, August 03, 2010 7:03 AM

SSC-Dedicated

Group: General Forum Members
Last Login: Today @ 5:19 PM
Points: 33,110, Visits: 27,035

Jack-408956 (8/3/2010)

None of this "with" stuff is working for us on MSSQL 2000...

Server: Msg 156, Level 15, State 1, Procedure subordinates, Line 2
Incorrect syntax near the keyword 'with'.

Is it a feature of MSSQL 2005 only?

Yes... "WITH" is a precursor to CTE's.

If you want to do this "stuff" in 2k, do an initial insert similar to the first part (above the UNION) of the CTE. Then, do a loop that does very similar to the second part of the CTE which will have nearly the same speed as the CTE and (haven't tried it with this particular table) will likely use about 1/3rd the number of reads. The second part of the CTE (or the loop) is NOT RBAR, in this case. Each iteration of the loop loads an entire level of the hierarchy no matter how wide a given level becomes.

That's all a recursive CTE does, by the way... it does an "initial load" and then loops the same way (and with the same impact on performance) as a While Loop.

In 2k, this method will give much better utility and performance than using the classic "Expanding Hierarchies" example given in 2k Books Online.

--Jeff Moden

"RBAR is pronounced "ree-bar" and is a "Modenism" for "Row-By-Agonizing-Row".

First step towards the paradigm shift of writing Set Based code:
Stop thinking about what you want to do to a row... think, instead, of what you want to do to a column."

For better, quicker answers on T-SQL questions, click on the following...
http://www.sqlservercentral.com/articles/Best+Practices/61537/

For better answers on performance questions, click on the following...
http://www.sqlservercentral.com/articles/SQLServerCentral/66909/

Post #962761

Jeff Moden

Posted Tuesday, August 03, 2010 7:09 AM

SSC-Dedicated

Group: General Forum Members
Last Login: Today @ 5:19 PM
Points: 33,110, Visits: 27,035

Jack-408956 (8/3/2010)

None of this "with" stuff is working for us on MSSQL 2000...

Server: Msg 156, Level 15, State 1, Procedure subordinates, Line 2
Incorrect syntax near the keyword 'with'.

Is it a feature of MSSQL 2005 only?

As a side bar, I'm writing an article/presentation on how to deal with Million Row Hierarchies... you just reminded me that there are still people out there that may need to do such a thing in MSSQL 2000 or earlier and that I need to include code for that in the presentation materials.

--Jeff Moden

Post #962766

« Prev Topic | Next Topic »

16 posts, Page 2 of 2

««1 2

Permissions