i have a table name conversion and i have these below mentioned columns in it i want to multiply Length\width row elements l*w of 'dimension' values and display them in another new table
Please let me know if anything changes for the same logic in ms access
probably it is simple but i dont know exact query to solve the problem waiting for your solutions
ID area length/width dimensions **new column(L*W) here**
1 1 l 3 3*5=15
2 1 w 5
3 2 l 4
4 2 w 8
5 3 l 6
6 3 w 10
7 4 l 12
8 4 w 13
9 4 W 10
waiting for your reply
You could query the table twice: once for lengths and once for widths and then join by area and multiply the values:
select length.area, length.dimension * width.dimension
from
(select area, dimension from conversion where lenwidth = 'l') length
inner join
(select area, dimension from conversion where lenwidth = 'w') width
on length.area = width.area;
Two remarks:
I suppose that it is a typo that you have two width entries for area 4? Otherwise you would have to decide which value to take in above select statement.
It would not be a good idea to keep the old table and have a new table holding the results. What if you change a value? You would have to remember to change the result accordingly every time. So either ditch the old table or use a view instead of a new table.
Try this
select *,
dimensions*(lead(dimensions) over(order by id)) product
from table1;
Or if you want for the set of area then
select *,
case when length_width='l' and (lead(length_width) over(order by id))='w'
then dimensions*(lead(dimensions) over(order by id))
else 0
end as product
from table1;
fiddle
Related
I have a simple task which I cannot wrap my head around being a novice coder.
I have a data set which I am trying to manipulate.
It appears as this:
UniqueID Day Var AverageVar
1 1 X
1 2 Y
1 3 Z
2 1 A
2 2 B
2 3 C
I would like to create this new "AverageVar" variable which computes an average across the three days for each unique ID.
So, for example, the AverageVar for the first three rows I would like to create and have (X + Y + Z)/3 displayed. Is there any easy code for this in SQL or R?
SELECT * INTO newtable
FROM
(SELECT UniqueID, AVG(Var) as AverageVar
FROM table
GROUP BY UniqueID);
SELECT O.UniqueID, O.Day, O.Var, N.AverageVar
FROM oldtable O
INNER JOIN
newtable N
ON O.UniqueID = N.UniqueID;
I have a query, let's call it qry_01, that produces a set of data similar to this:
ID N CN Sum
1 4 0 0
2 3 3 3
5 4 4 7
8 3 3 10
The values shown in this query actually come from a chain of queries and from a bunch of different tables.
The corrected value CN is calculated within the query, and counts N if the ID is not 1, and 0 if it is 1.
The Sum is the value I want to calculate by progressively summing up the CN values.
I tried to use DSUM, but I came out with nothing.
Can anyone please help me?
You could use a correlated subquery in the following way:
select t.id, t.n, t.cn, (select sum(u.cn) from qry_01 u where u.id <= t.id) as [sum]
from qry_01 t
I have a child table with a number of charact/value pairs for a given 'material' (MaterialID). Any material can have a number of charact values and may have several of the same name (see id's 2,3).
The table has a large number of records (8+ million). What I'm trying to do is find the materials that are the most similar to a supplied material. That is, when I supply a MaterialID, I would like an ordered list of the most similar other materials (those with the most matching charact/value pairs).
I've done some research but, I may be missing some key terms or just not conceptualizing the problem correctly.
Any hints as to how to go about this would be very much appreciated.
ID MaterialID Charact Value
1 1 ROT_DIR CCW
2 1 SPECIAL_FEATURE CATALOG_CP
3 1 SPECIAL_FEATURE CHROME
4 1 SCHEDULE 80
5 2 BEARING_TYPE SB
6 2 SCHEDULE 80
7 3 ROT_DIR CCW
8 3 SPECIAL_FEATURE CATALOG_HSB
9 3 BEARING_TYPE SP
10 4 NDE_STYLE W_FAN
11 4 BEARING_TYPE SB
12 4 ROT_DIR CW*
You can do this with a self join:
select t.materialid, count(*) as nummatches
from t join
t tmat
on t.Charact = tmat.Charact and t.value = tmat.value
where tmat.materialid = #MaterialId
group by t.materialid
order by nummatches desc;
Notes:
You might want to remove the specified material, by adding where t.MaterialId <> tmat.MaterialId to the where clause.
If you want all materials, then make the join a left join and move the where condition to the on clause.
If you want only one material with the most matches, use select top 1.
If you want all materials with the most matches when there are ties, use `select top (1) with ties.
I have a source data set like this (simplified to be more clear):
Key F1 F2
1 X 4
2 X 5
3 Y 6
4 X 9
5 X 7
6 X 8
7 Y 9
8 X 6
9 X 5
10 Y 3
The data is sorted by the Key field. Now, I want to compute an aggregate of the F2 field over partitions that are defined by the F1 field: A partition starts at the first X value and ends with the first subsequent Y value.
So, for example, I might want wo compute the MIN() over the partitions defined as described above. Then the result set would look like this:
rownum MIN(F2)
1 4
2 7
3 3
I have tried a number of resources (incl. our own intranet community and of course stackoverflow) but found nothing for my case. Usually partitioning only works with a field that can be used to identify the partitions. Here, the partitions are defined by a change in a field's content with respect to a given order.
Although I am aware that I may have to resort to writing a procedural solution I would prefer to solve this in pure SQL.
Any ideas how such a partitioning could be achieved with a SQL select statement?
Thanks and regards
Kai.
A little bit shorter solution: http://sqlfiddle.com/#!12/7390d/24
Query:
select min(f2)
from t t1
group by (select max(key)
from t t2
where t2.f1='Y' and
t1.key > t2.key)
Result:
| MIN |
-------
| 4 |
| 7 |
| 3 |
The idea is to find the key of preceding 'Y' for each row and group by it. Should work with any SQL engine.
You didn't specify engine or dialect or version so I assumed SQL Server 2012.
Example that you can run to see the solution: http://sqlfiddle.com/#!6/f5d38/21
You solve it by creating correct partitions in your set. Code looks like this.
WITH groupLimits as
(
SELECT
[Key] AS groupend
,COALESCE(LAG([Key]) OVER (order by [Key]),0)+1 AS groupstart
FROM sourceData
WHERE F1 = 'Y'
)
SELECT
MIN(sourceData.F2)
FROM groupLimits
INNER JOIN sourceData
ON sourceData.[Key] BETWEEN groupLimits.groupstart and groupLimits.groupend
GROUP BY groupLimits.groupstart
ORDER BY groupLimits.groupstart
I am a long time fan of Stack Overflow but I've come across a problem that I haven't found addressed yet and need some expert help.
I have a query that is sorted chronologically with a date-time compound key (unique, never deleted) and several pieces of data. What I want to know is if there is a way to find the start (or end) of a region where a value changes? I.E.
DateTime someVal1 someVal2 someVal3 target
1 3 4 A
1 2 4 A
1 3 4 A
1 2 4 B
1 2 5 B
1 2 5 A
and my query returns rows 1, 4 and 6. It finds the change in col 5 from A to B and then from B back to A? I have tried the find duplicates method and using min and max in the totals property however it gives me the first and last overall instead of the local max and min? Any similar problems?
I didn't see any purpose for the someVal1, someVal2, and someVal3 fields, so I left them out. I used an autonumber as the primary key instead of your date/time field; but this approach should also work with your date/time primary key. This is the data in my version of your table.
pkey_field target
1 A
2 A
3 A
4 B
5 B
6 A
I used a correlated subquery to find the previous pkey_field value for each row.
SELECT
m.pkey_field,
m.target,
(SELECT Max(pkey_field)
FROM YourTable
WHERE pkey_field < m.pkey_field)
AS prev_pkey_field
FROM YourTable AS m;
Then put that in a subquery which I joined to another copy of the base table.
SELECT
sub.pkey_field,
sub.target,
sub.prev_pkey_field,
prev.target AS prev_target
FROM
(SELECT
m.pkey_field,
m.target,
(SELECT Max(pkey_field)
FROM YourTable
WHERE pkey_field < m.pkey_field)
AS prev_pkey_field
FROM YourTable AS m) AS sub
LEFT JOIN YourTable AS prev
ON sub.prev_pkey_field = prev.pkey_field
WHERE
sub.prev_pkey_field Is Null
OR prev.target <> sub.target;
This is the output from that final query.
pkey_field target prev_pkey_field prev_target
1 A
4 B 3 A
6 A 5 B
Here is a first attempt,
SELECT t1.Row, t1.target
FROM t1 WHERE (((t1.target)<>NZ((SELECT TOP 1 t2.target FROM t1 AS t2 WHERE t2.DateTimeId<t1.DateTimeId ORDER BY t2.DateTimeId DESC),"X")));