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Hierarchies on Steroids #2: A Replacement for Nested Sets Calculations


Hierarchies on Steroids #2: A Replacement for Nested Sets Calculations

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Jeff Moden
Jeff Moden
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Comments posted to this topic are about the item Hierarchies on Steroids #2: A Replacement for Nested Sets Calculations

--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.
Although they tell us that they want it real bad, our primary goal is to ensure that we dont actually give it to them that way.
Although change is inevitable, change for the better is usually not.
Just because you can do something in PowerShell, doesnt mean you should. Wink

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Theo Ekelmans
Theo Ekelmans
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Another excellent article, John ! This is really usefull.

Keep e'm coming :-)

Theo
(NL)
Jeff Moden
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Theo Ekelmans (11/15/2012)
Another excellent article, John ! This is really usefull.

Keep e'm coming :-)

Theo
(NL)


Thanks, Theo. (my name isn't "John", though ;-)).

--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.
Although they tell us that they want it real bad, our primary goal is to ensure that we dont actually give it to them that way.
Although change is inevitable, change for the better is usually not.
Just because you can do something in PowerShell, doesnt mean you should. Wink

Helpful Links:
How to post code problems
How to post performance problems
Forum FAQs
Michael Meierruth
Michael Meierruth
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They both start with J. He was close.:-)
SQLRNNR
SQLRNNR
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Another fine piece Jeff.



Jason AKA CirqueDeSQLeil
I have given a name to my pain...
MCM SQL Server, MVP


SQL RNNR

Posting Performance Based Questions - Gail Shaw

JJ B
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Wow. Both articles are awesome. Not only is your code well documented (as usual), but the charts were also extremely useful in helping to explain the text. Well done and thanks for taking the time to really explain the methods.
adrian.facio
adrian.facio
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Learned a lot.
dwain.c
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Jeff - Working through it now but its pretty deep and I expect it will take me awhile.

Great explanations though!

I'm going to try to see if I can adapt the approach to another problem I encountered recently that is "not quite" a hiearchy.

Let me know if you decide to change your name to John. I have several article attributions to you I'll need to change.:-D


My mantra: No loops! No CURSORs! No RBAR! Hoo-uh!

My thought question: Have you ever been told that your query runs too fast?

My advice:
INDEXing a poor-performing query is like putting sugar on cat food. Yeah, it probably tastes better but are you sure you want to eat it?
The path of least resistance can be a slippery slope. Take care that fixing your fixes of fixes doesn't snowball and end up costing you more than fixing the root cause would have in the first place.


Need to UNPIVOT? Why not CROSS APPLY VALUES instead?
Since random numbers are too important to be left to chance, let's generate some!
Learn to understand recursive CTEs by example.
Splitting strings based on patterns can be fast!
My temporal SQL musings: Calendar Tables, an Easter SQL, Time Slots and Self-maintaining, Contiguous Effective Dates in Temporal Tables
Jeff Moden
Jeff Moden
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Michael Meierruth (11/15/2012)
They both start with J. He was close.:-)


4 Letters, too! :-P

--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.
Although they tell us that they want it real bad, our primary goal is to ensure that we dont actually give it to them that way.
Although change is inevitable, change for the better is usually not.
Just because you can do something in PowerShell, doesnt mean you should. Wink

Helpful Links:
How to post code problems
How to post performance problems
Forum FAQs
Jeff Moden
Jeff Moden
SSC-Forever
SSC-Forever (44K reputation)SSC-Forever (44K reputation)SSC-Forever (44K reputation)SSC-Forever (44K reputation)SSC-Forever (44K reputation)SSC-Forever (44K reputation)SSC-Forever (44K reputation)SSC-Forever (44K reputation)

Group: General Forum Members
Points: 44968 Visits: 39862
dwain.c (11/15/2012)
Jeff - Working through it now but its pretty deep and I expect it will take me awhile.

Great explanations though!

I'm going to try to see if I can adapt the approach to another problem I encountered recently that is "not quite" a hiearchy.

Let me know if you decide to change your name to John. I have several article attributions to you I'll need to change.:-D


Thanks, Dwain. I'd be interested in your "not quite a hierarchy" problem. Sounds interesting.

Heh... nah. Not going to change my name. Too much paper work for us all. :-D

--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.
Although they tell us that they want it real bad, our primary goal is to ensure that we dont actually give it to them that way.
Although change is inevitable, change for the better is usually not.
Just because you can do something in PowerShell, doesnt mean you should. Wink

Helpful Links:
How to post code problems
How to post performance problems
Forum FAQs
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