I want to create Row Number by Column based on each Product ID and back to 1 for another Product ID.
Pack ID
Product ID
Row Number
A001
P001
1
A002
P001
2
A003
P001
3
A004
P002
1
A005
P002
2
A006
P003
1
A007
P004
1
A008
P004
2
What query should I write ?
Use the ROW_NUMBER window function (see here and here).
select pack_id
, product_id
, row_number() over (partition by product_id
order by pack_id) "row number"
from test;
demo.
Related
I have a child table called wbs_numbers. the primary key id is a ltree
A typical example is
id
series_id
abc.xyz.00001
1
abc.xyz.00002
1
abc.xyz.00003
1
abc.xyz.00101
1
so the parent table called series. it has a field called last_contigous_max.
given the above example, i want the series of id 1 to have its last contigous max be 3
can always assume that the ltree of wbs is always 3 fragment separated by dot. and the last fragment is always a 5 digit numeric string left padded by zero. can always assume the first child is always ending with 00001 and the theoretical total children of a series will never exceed 9999.
If you think of it as gaps and islands, the wbs_numbers will never start with a gap within a series. it will always start with an island.
meaning to say this is not possible.
id
series_id
abc.xyz.00010
1
abc.xyz.00011
1
abc.xyz.00012
1
abc.xyz.00101
1
This is possible
id
series_id
abc.xyz.00001
1
abc.xyz.00004
1
abc.xyz.00005
1
abc.xyz.00051
1
abc.xyz.00052
1
abc.xyz.00100
1
abc.xyz.10001
2
abc.xyz.10002
2
abc.xyz.10003
2
abc.xyz.10051
2
abc.xyz.10052
2
abc.xyz.10100
2
abc.xyz.20001
3
abc.xyz.20002
3
abc.xyz.20003
3
abc.xyz.20004
3
abc.xyz.20052
3
abc.xyz.20100
3
so the last max contiguous in this case is
for series id 1 => 1
for series id 2 => 3
for series id 3 => 4
What's the query to calculate the last_contigous_max number for any given series_id?
I also don't mind having another table just to store "islands".
Also, you can safely assume that wbs_number records will never be deleted once created. The id in the wbs_numbers table will never be altered once filled in as well.
Meaning to say islands will only grow and never shrink.
You can carry out your problem following these steps:
extract your integer value from your "id" field
compute a ranking value sided with your id value
filter out when your ranking value does not match your id value
get tied last row for each of your matches
WITH cte AS (
SELECT *, CAST(RIGHT(id_, 4) AS INTEGER) AS idval
FROM tab
), ranked AS (
SELECT *,
ROW_NUMBER() OVER(PARTITION BY series_id ORDER BY idval) AS rn
FROM cte
)
SELECT series_id, idval
FROM ranked
WHERE idval = rn
ORDER BY ROW_NUMBER() OVER(PARTITION BY series_id ORDER BY idval DESC)
FETCH FIRST ROWS WITH TIES
Check the demo here.
I have a table like this
item_id date number
1 2000-01-01 100
1 2003-03-08 50
1 2004-04-21 10
1 2004-12-11 10
1 2010-03-03 10
2 2000-06-29 1
2 2002-05-22 2
2 2002-07-06 3
2 2008-10-20 4
I'm trying to get the average for each uniq Item_id over the last 3 dates.
It's difficult because there are missing date in between so a range of hardcoded dates doesn't always work.
I expect a result like :
item_id MyAverage
1 10
2 3
I don't really know how to do this. Currently i manage to do it for one item but i have trouble extending it to multiples items :
SELECT AVG(MyAverage.number) FROM (
SELECT date,number
FROM item_list
where item_id = 1
ORDER BY date DESC limit 3
) as MyAverage;
My main problem is with generalising the "DESC limit 3" over a group by id.
attempt :
SELECT item_id,AVG(MyAverage.number)
FROM (
SELECT item_id,date,number
FROM item_list
ORDER BY date DESC limit 3) as MyAverage
GROUP BY item_id;
The limit is messing things up there.
I have made it " work " using between date and date but it's not working as i want because i need a limit and not an hardcoded date..
Can anybody help
You can use row_number() to assign 1 to 3 for the records with the last date for an ID an then filter for that.
SELECT x.item_id,
avg(x.number)
FROM (SELECT il.item_id,
il.number,
row_number() OVER (PARTITION BY il.item_id
ORDER BY il.date DESC) rn
FROM item_list il) x
WHERE x.rn BETWEEN 1 AND 3
GROUP BY x.item_id;
Id values
1 10
1 20
1 30
1 40
2 3
2 9
2 0
3 14
3 5
3 7
Answer should be
Id values
1 30
2 3
3 7
I tried as below
Select distinct
id,
(select max(values)
from table
where values not in(select ma(values) from table)
)
You need the row_number window function. This adds a column with a row count for each group (in your case the ids). In a subquery you are able to ask for the second row of each group.
demo:db<>fiddle
SELECT
id, values
FROM (
SELECT
*,
row_number() OVER (PARTITION BY id ORDER BY values DESC)
FROM
table
) s
WHERE row_number = 2
I have an 'order' column in a table in a postgres database that has a lot of missing numbers in the sequence. I am having a problem figuring out how to replace the numbers currently in the column, with new ones that are incremental (see examples).
What I have:
id order name
---------------
1 50 Anna
2 13 John
3 2 Bruce
4 5 David
What I want:
id order name
---------------
1 4 Anna
2 3 John
3 1 Bruce
4 2 David
The row containing the lowest order number in the old version of the column should get the new order number '1', the next after that should get '2' etc.
You can use the window function row_number() to calculate the new numbers. The result of that can be used in an update statement:
update the_table
set "order" = t.rn
from (
select id, row_number() over (order by "order") as rn
from the_table
) t
where t.id = the_table.id;
This assumes that id is the primary key of that table.
My data is in the following format:
rep_id user_id other non-duplicated data
1 1 ...
1 2 ...
2 3 ...
3 4 ...
3 5 ...
I am trying to achieve a column for deduped_rep with 0/1 such that only first rep id across the associated users has a 1 and rest have 0.
Expected result:
rep_id user_id deduped_rep
1 1 1
1 2 0
2 3 1
3 4 1
3 5 0
For reference, in Excel, I would use the following formula:
IF(SUMPRODUCT(($A$2:$A2=A2)*($A$2:$A2=A2))>1,0,1)
I know there is the FIXED() LoD calculation http://kb.tableau.com/articles/howto/removing-duplicate-data-with-lod-calculations, but I only see use cases of it deduplicating based on another column. However, mine are distinct.
Define a field first_reg_date_per_rep_id as
{ fixed rep_id : min(registration_date) }
The define a field is_first_reg_date? as
registration_date = first_reg_date_per_rep_id
You can use that last Boolean field to distinguish the first record for each rep_id from later ones
try this query
select
rep_id,
user_id,
row_number() over(partition by rep_id order by rep_id,user_id) deduped_rep
from
table