SQL 3D Volumetric Banding Calulations - sql

Question

I Come across below problem and not sure how to get it sorted:
We have a dimensions of the boxes in database:
L,W,H
As the box may be measured in random position , for example the values for Lenght may be allocated in to Height column etc.
Now , we have a band for boxes which contains two conditions regarding the dimensions:
Band:
Every Box with Maximum of 24x34x6
OR
Every Box with Maximum of 21x21x21
To calculate this by AND , OR statements will be possible but we will end up with 100's of lines of code only for first condition as the number of combinations will be 27 and then this will need to by applied in sql statement for each of the columns H,L,W.
I managed to get the total number of combinations by cross join but how to apply that to CASE statement and get reasonable performance and amount of code ?
CREATE TABLE #XMS1
( XMS1 int)
INSERT #XMS1 select 6
INSERT #XMS1 select 24
INSERT #XMS1 select 34
select
a.XMS1 as H,
b.XMS1 as L,
c.XMS1 as W
from #XMS1 as a
cross join #XMS1 b
cross join #XMS1 c
The values of L,W,H can be everyting from 0 to 100 but I need to select only the lines which fits in to the band...

Answer 1

Oracle:
You can use this to order the dimensions and then just filter on smallest, middle and largest:
SELECT *
FROM (
SELECT LEAST( l, w, h ) AS small,
l + w + h - LEAST( l, w, h ) - GREATEST( l, w, h ) AS middle,
GREATEST( l, w, h ) AS large
FROM your_box_dimensions_table
)
WHERE ( small <= 6 AND middle <= 24 AND large <= 36 )
OR ( small <= 21 AND middle <= 21 AND large <= 21 ) -- or more simply: large <= 21
;
SQL Server:
Since SQL Server does not appear to have a LEAST or GREATEST function, you could just write a user-defined function for LEAST and GREATEST with three inputs and then just call that to mimic the Oracle solution.
Or:
SELECT *
FROM (
SELECT CASE
WHEN l <= w AND l <= h THEN l
WHEN w <= h THEN w
ELSE h
END AS small,
CASE
WHEN w <= l AND l <= h THEN l
WHEN h <= l AND l <= w THEN l
WHEN l <= w AND w <= h THEN w
WHEN h <= w AND w <= l THEN w
ELSE h
END AS middle,
CASE
WHEN l >= w AND l >= h THEN l
WHEN w >= h THEN w
ELSE h
END AS large
FROM your_box_dimensions_table
)
WHERE ( small <= 6 AND middle <= 24 AND large <= 36 )
OR ( small <= 21 AND middle <= 21 AND large <= 21 ); -- or more simply: large <= 21

Answer 2

Daniel, I think #MT0 has answered this so don't mark this as an answer I'm just simply expanding his answer into a complete example.
This first step is simply building a list of values between 1 and 100 to help create the table containing box dimensions.
DECLARE #n TABLE (n int)
INSERT INTO #n
SELECT ones.n + 10*tens.n +1
FROM (VALUES(0),(1),(2),(3),(4),(5),(6),(7),(8),(9)) ones(n),
(VALUES(0),(1),(2),(3),(4),(5),(6),(7),(8),(9)) tens(n)
ORDER BY 1
Now creating a physical table Boxes to store each combination of box dimensions (1 million records)
CREATE TABLE Boxes (d1 int, d2 int, d3 int)
INSERT INTO Boxes
SELECT a.n, b.n, c.n
FROM #n a
cross join #n b
cross join #n c
Now create a view over this table with three additional columns, these will hold the dimensions in size order (small medium, large) (thanks to MT0 for saving me having to type all that out!)
You could also use a physical table instead of a view but this way offers a bit more flexibility if requirements change.
CREATE VIEW BoxesExtended AS
select
*
, CASE
WHEN d1 <= d2 AND d1 <= d3 THEN d1
WHEN d2 <= d3 THEN d2
ELSE d3
END AS small
, CASE
WHEN d2 <= d1 AND d1 <= d3 THEN d1
WHEN d3 <= d1 AND d1 <= d2 THEN d1
WHEN d1 <= d2 AND d2 <= d3 THEN d2
WHEN d3 <= d2 AND d2 <= d1 THEN d2
ELSE d3
END AS middle
, CASE
WHEN d1 >= d2 AND d1 >= d3 THEN d1
WHEN d2 >= d3 THEN d2
ELSE d3
END AS large
from Boxes
Now all we have to do is query the view to get the boxes that match your criteria
SELECT *
FROM BoxesExtended
WHERE (large <=34 and middle <=24 and small <=6)
OR (large <=21 and middle <=21 and small <=21)
You could extend this by having a 'Bands' table along the lines of
BandID BandName MaxSmall MaxMiddle MaxLarge
1 BandA 6 24 36
2 BandA 21 21 21
3 BandB 30 40 50
and then join this to the BoxesExtended view. This would allow you to define bands and then query against the view to get matching boxes within each BandName