I have a table that contains the count of products by region
Products
-id
-name
Regions
-id
-product_count
Inventory
-id
-product_id
-region_id
I want to update the Regions table with the count of product_id + region_id in the Inventory table.
This would give me all the products for a single region:
select COUNT(*) as product_count
from inventory
where region_id=1
But I need to update the Regions.product_count column for all products and regions.
How can I perform this batch update?
Update regions
set product_count = ??
from Regions
You can use an aggregation to retrieve counts for every region. Then use a JOIN operation inside the UPDATE statement to associate your counts to your "regions" table, and update the value of "regions.product_count" accordingly.
WITH cte AS (
SELECT region_id, COUNT(*) AS num_products
FROM inventory
GROUP BY region_id
)
UPDATE regions
SET product_count = cte.num_products
FROM cte
WHERE regions.region_id = cte.region_id
Related
Firstly, I'm so sorry with the basic question. I want to sum child data and count number of transaction as the following field:
amount (totally)
level (totalLevel)
number of trasanction (Transaction Times)
I have 2 table which related. One user has many transaction.
User Table
id
name
Transaction Table
id
user_id
amount
level
Here is query that I have test. But, it seem not work as expected:
const query = `
SELECT
u.*,
't.amount',
't.level'
COUNT('t.amountDiffCents') as "numberOfTransaction",
SUM('t.level') as "Total Level",
COUNT(u.*) OVER () as "totalCount"
FROM "LoyaltyUser" as u
INNER JOIN "Transaction" as t ON u.id = 't.userId'
GROUP BY u.id
LIMIT $limit
OFFSET $offset;
`;
Thank beforehand.
Aggregate the Transactions table separately, then JOIN Users only afterwards:
SELECT
u.*,
agg.txn_count,
agg.sum_level
FROM
(
SELECT
t.user_id,
COUNT(*) AS txn_count,
SUM( t.level ) AS sum_level
FROM
transaction AS t
GROUP BY
t.user_id
) AS agg
INNER JOIN loyalty_user AS u ON
u.uid = agg.user_id
Strictly speaking (ISO SQL) it is not possible to meaningfully include the total number of all transaction rows in this single result-set (at least, not without having a repeating value in every row, ew). Instead that can be trivially performed by application code - or use a second query in the same batch.
I have created synthetic data for a typical call center.
Below is the screenshot of the table I have created.
Table 1:
Problem statement: Since this is completely random data, I noticed that there are some customers who are being assigned to the same agents whenever they call again.
So using this query I was able to test such a case and count the number of times agents are being repeated for each customer.
select agentid, customerid, count(customerid) from aa_dev.calls group by agentid, customerid having count(customerid) > 1 ;
Table 2
I have a separate agents table to called aa_dev.agents in which the agent's ids are stored
Now I want to replace the agentid for such cases, such that if agentid is repeated 6 times for a single customer then 5 of the times the agent id should be updated with any other agentid from the table but call time shouldn't be overlapping That means the agent we are replacing with should not be busy on the time the call is going one.
I have assigned row numbers to each repeated ones.
WITH cte AS (
SELECT *, ROW_NUMBER() OVER (PARTITION BY agentid, customerid ORDER BY random()) rn,
COUNT(*) OVER (PARTITION BY agentid, customerid) cnt
FROM aa_dev.calls
)
SELECT agentid, customerid, rn
FROM cte
WHERE cnt > 1;
This way I could visualize the repetition clearly.
So I don't want to update row 1 but the rest.
Is there any way I can acheive this? Can I use the row number and write a query according to the row number to update rownum 2 onwards row one by one with each row having a unique agent?
If you don't want duplicates in your artificial data, it's probably better to not generate them.
But if you already have a table with duplicates and want to work on the duplicates, either updating them or deleting, here is the easy way:
You need a unique ID for each updated row. If you don't have it,
add it temporarily. Then you can use this pattern to update all duplicates
except the first one:
To add artificial id column to preexisting table, use:
ALTER TABLE calls ADD id serial;
In my case I generated a test table with 100 random rows:
CREATE TEMP TABLE calls (id serial, agentid int, customerid int);
INSERT INTO calls (agentid, customerid)
SELECT (random()*10)::int, (random()*10)::int
FROM generate_series(1, 100) n;
Define what constitutes a duplicate and find duplicates in data:
SELECT agentid, customerid, count(*), array_agg(id) id
FROM calls
GROUP BY 1,2 HAVING count(*)>1
ORDER BY 1,2;
Update all the duplicate rows except first one with NULLs:
UPDATE calls SET agentid = whatever_needed
FROM (
SELECT array_agg(id) id, min(id) idmin FROM calls
GROUP BY agentid, customerid HAVING count(*)>1
) AS dup
WHERE calls.id = ANY(dup.id) AND calls.id <> dup.idmin;
Alternatively, remove all duplicates except first one:
DELETE FROM calls
USING (
SELECT array_agg(id) id, min(id) idmin FROM calls
GROUP BY agentid, customerid HAVING count(*)>1
) AS dup
WHERE calls.id = ANY(dup.id) AND calls.id <> dup.idmin;
I need to perform an update to a field in a table with a variable, but I need the variable to change when the group changes. It is just an INTt, so for example if I The example below I want to update the record of texas with a 1 and flordia with the next number of 2:
UPDATE table
set StateNum = #Count
FROM table
where xxxxx
GROUP BY state
Group Update Variable
Texas 1
Texas 1
Florida 2
Florida 2
Florida 2
I think you should use a lookup table with the state and its number StateNum Then you should store this number instead of the name to your table.
You might use DENSE_RANK within an updateable CTE:
--mockup data
DECLARE #tbl TABLE([state] VARCHAR(100),StateNum INT);
INSERT INTO #tbl([state]) VALUES
('Texas'),('Florida'),('Texas'),('Nevada');
--your update-statement
WITH updateableCTE AS
(
SELECT StateNum
,DENSE_RANK() OVER(ORDER BY [state]) AS NewValue
FROM #tbl
)
UPDATE updateableCTE SET StateNum=NewValue;
--check the result
SELECT * FROM #tbl;
And then you should use this to get the data for your lookup table
SELECT StateNum,[state] FROM #tbl GROUP BY StateNum,[state];
Then drop the state-column from your original table and let the StateNum be a foreign key.
I have a Table that I am using to pull order details in SSRS that has when the price of a product number was changed. It has Data Changed and Updated Cost.
I am pairing up two different tables to create a report that is the cost of the package at the time of the order. Here is how I am pulling my data:
SELECT
WAREHOUSE.ActPkgCostHist.ItemNo AS [ActPkgCostHist ItemNo]
,WAREHOUSE.ActPkgCostHist.ActPkgCostDate
,WAREHOUSE.ActPkgCostHist.ActPkgCost
,ORDER.OrderHist.OrderNo
,ORDER.OrderHist.ItemNo AS [OrderHist ItemNo]
,ORDER.OrderHist.DispenseDt
FROM
WAREHOUSE.ActPkgCostHist
INNER JOIN ORDER.OrderHist
ON WAREHOUSE.ActPkgCostHist.ItemNo = ORDER.OrderHist.ItemNo
Catalog=ShippedOrders
ActPkgCostHist Table has What the cost of an Item was and what date the cost was changed.
OrderHist Table has the complete details of the order except the ActPkgCost at the time of the purchase.
I am attempting to create a table that Has order number, the date of the order and the package cost at the time of the order.
The ROW_NUMBER function is very useful for cases like this.
SELECT WAREHOUSE.ActPkgCostHist.ItemNo AS [ActPkgCostHist ItemNo]
,WAREHOUSE.ActPkgCostHist.ActPkgCostDate
,WAREHOUSE.ActPkgCostHist.ActPkgCost
,ORDER.OrderHist.OrderNo
,ORDER.OrderHist.ItemNo AS [OrderHist ItemNo]
,ORDER.OrderHist.DispenseDt
FROM ORDER.OrderHist
INNER JOIN (
SELECT ItemNo, ActPkgCostDate, ActPkgCost
, ROW_NUMBER() OVER (PARTITION BY ItemNo ORDER BY ActPkgCostDate DESC) as RN
FROM WAREHOUSE.ActPkgCostHist
--if there are future dated changes, limit ActPkgCostDate to be <= the current date
) ActPkgCostHist on ActPkgCostHist.ItemNo = OrderHist.ItemNo
WHERE RN = 1
What this subquery does is group the cost history by ItemNo. Then for each one, it ranks the changes by recency with the most recent change being 1. Then in the main query you filter it to just rows with a 1.
For each item in each order you have to find the latest cost date and use it when joining with the cost table
SELECT C.ItemNo AS [ActPkgCostHist ItemNo],
C.ActPkgCostDate,
C.ActPkgCost,
O.OrderNo,
O.ItemNo AS [OrderHist ItemNo],
O.DispenseDt
FROM WAREHOUSE.ActPkgCostHist AS C
-- JOIN order detail with cost table in order to define the cost date per item/order
INNER JOIN (SELECT Max(CH.ActPkgCostDate) AS ItemCostDate,
OH.OrderNo,
OH.ItemNo,
OH.DispenseDt
FROM WAREHOUSE.ActPkgCostHist AS CH
INNER JOIN ORDER.OrderHist AS OH
ON CH.ItemNo = OH.ItemNo
-- Get the latest cost date only from dates before order date
WHERE CH.ActPkgCostDate <= OH.DispenseDt
GROUP BY OH.OrderNo,
OH.ItemNo,
OH.DispenseDt) AS O
ON C.ItemNo = O.ItemNo
AND C.ActPkgCostDate = O.ItemCostDate
For Postgresql 8.x, I have an answers table containing (id, user_id, question_id, choice) where choice is a string value. I need a query that will return a set of records (all columns returned) for all unique choice values. What I'm looking for is a single representative record for each unique choice. I also want to have an aggregate votes column that is a count() of the number of records matching each unique choice accompanying each record. I want to force choice to lowercase for this comparison to be made (HeLLo and Hello should be considered equal). I can't GROUP BY lower(choice) because I want all columns in the result-set. Grouping by all columns causes all records to return, including all duplicates.
1. Closest I've gotten
select lower(choice), count(choice) as votes from answers where question_id = 21 group by lower(choice) order by votes desc;
The issue with this is it will not return all columns.
lower | votes
-----------------------------------------------+-------
dancing in the moonlight | 8
pumped up kicks | 7
party rock anthem | 6
sexy and i know it | 5
moves like jagger | 4
2. Trying with all columns
select *, count(choice) as votes from answers where question_id = 21 group by lower(choice) order by votes desc;
Because I am not specifying every column from the SELECT in my GROUP BY, this throws an error telling me to do so.
3. Specifying all columns in the GROUP BY
select *, count(choice) as votes from answers where question_id = 21 group by lower(choice), id, user_id, question_id, choice order by votes desc;
This simply dumps the table with votes column as 1 for all records.
How can I get the vote count and unique representative records from 1., but with all columns from the table returned?
Join grouped results back with primary table, then show only one row for each (question,answer) combination.
similar to this:
WITH top5 AS (
select question_id, lower(choice) as choice, count(*) as votes
from answers
where question_id = 21
group by question_id , lower(choice)
order by count(*) desc
limit 5
)
SELECT DISTINCT ON(question_id,choice) *
FROM top5
JOIN answers USING(question_id,lower(choice))
ORDER BY question_id, lower(choice), answers.id;
Here's what I ended up with:
SELECT answers.*, cc.votes as votes FROM answers join (
select max(id) as id, count(id) as votes
from answers
group by trim(lower(choice))
) cc
on answers.id = cc.id ORDER BY votes desc, lower(response) asc