SELECT lkey, max(votecount) FROM VOTES
WHERE ekey = (SELECT ekey FROM Elections where electionid='NR2019')
GROUP BY lkey
ORDER BY lkey ASC
Is there an easy way to get the pkey in this Statement?
Solution should look like this
Use DISTINCT ON:
SELECT DISTINCT ON (v.ikey) v.*
FROM VOTES v
INNER JOIN Elections e ON e.ekey = v.ekey
WHERE e.electionid = 'NR2019'
ORDER BY v.ikey, v.votecount DESC;
In plain English, the above query says to return the single record for each ikey value having the highest vote count.
Related
SELECT user_posts.id,
COUNT(user_post_comments.post_id) as number_of_comments,
COUNT(user_post_reactions.post_id) as number_of_reactions
FROM user_posts
LEFT JOIN user_post_comments
ON (user_posts.id = user_post_comments.post_id)
LEFT JOIN user_post_reactions
ON (user_posts.id = user_post_reactions.post_id)
WHERE user_posts.user_id = '850e6511-2f30-472d-95a1-59a02308b46a'
group by user_posts.id
I have this query for getting the number of comments and reactions from another table by post_id
current output screenshot
To caluclate number of comments and reactions just use subqueries. No need to join and group by.
SELECT user_posts.id,
( select COUNT(*) from user_post_comments
where user_posts.id = user_post_comments.post_id
) as number_of_comments,
( select COUNT(*) from user_post_reactions
where user_posts.id = user_post_reactions.post_id
) as number_of_reactions
FROM user_posts
WHERE user_posts.user_id = '850e6511-2f30-472d-95a1-59a02308b46a'
If both joins return non-null rows, what you get for each count is the product of the number of rows from each for a given user_posts.id. One way you could fix that is by counting distinct identifiers for each table, e.g.
COUNT(DISTINCT user_post_comments.id) as number_of_comments
(Assuming "id" exists as a primary key on that table). This may not be spectacularly efficient, but is relatively simple.
I have two tables that look like the following:
Orders
------
id
tracking_number
ShippingLogs
------
tracking_number
created_at
stage
I would like to select the IDs of Orders that have ONLY ONE ShippingLog associated with it, and the stage of the ShippingLog must be error. If it has two ShippingLog entries, I don't want it. If it has one ShippingLog bug its stage is shipped, I don't want it.
This is what I have, and it doesn't work, and I know why (it finds the log with the error, but has no way of knowing if there are others). I just don't really know how to get it the way I need it.
SELECT DISTINCT
orders.id, shipping_logs.created_at, COUNT(shipping_logs.*)
FROM
orders
JOIN
shipping_logs ON orders.tracking_number = shipping_logs.tracking_number
WHERE
shipping_logs.created_at BETWEEN '2021-01-01 23:40:00'::timestamp AND '2021-01-26 23:40:00'::timestamp AND shipping_logs.stage = 'error'
GROUP BY
orders.id, shipping_logs.created_at
HAVING
COUNT(shipping_logs.*) = 1
ORDER BY
orders.id, shipping_logs.created_at DESC;
If you want to retain every column from the join of the two tables given your requirements, then I would suggest using COUNT here as an analytic function:
WITH cte AS (
SELECT o.id, sl.created_at,
COUNT(*) OVER (PARTITION BY o.id) num_logs,
COUNT(*) FILTER (WHERE sl.stage <> 'error')
OVER (PARTITION BY o.id) non_error_cnt
FROM orders o
INNER JOIN shipping_logs sl ON sl.tracking_number = o.tracking_number
WHERE sl.created_at BETWEEN '2021-01-01 23:40:00'::timestamp AND
'2021-01-26 23:40:00'::timestamp
)
SELECT id AS order_id, created_at
FROM cte
WHERE num_logs = 1 AND non_error_cnt = 0
ORDER BY id, created_at DESC;
I have a query like this:
SELECT
table1.*,
sum(table2.amount) as totalamount
FROM table1
join table2 on table1.key = table2.key
GROUP BY table1.*;
I got the error: column "table1.key" must appear in the GROUP BY clause or be used in an aggregate function.
Are there any way to group "all" field?
There is no shortcut syntax for grouping by all columns, but it's probably not necessary in the described case. If the key column is a primary key, it's enough when you use it:
GROUP BY table1.key;
You have to specify all the column names in group by that are selected and are not part of aggregate function ( SUM/COUNT etc)
select c1,c2,c4,sum(c3) FROM totalamount
group by c1,c2,c4;
A shortcut to avoid writing the columns again in group by would be to specify them as numbers.
select c1,c2,c4,sum(c3) FROM t
group by 1,2,3;
I found another way to solve, not perfect but maybe it's useful:
SELECT string_agg(column_name::character varying, ',') as columns
FROM information_schema.columns
WHERE table_schema = 'your_schema'
AND table_name = 'your_table
Then apply this select result to main query like this:
$columns = $result[0]["columns"];
SELECT
table1.*,
sum(table2.amount) as totalamount
FROM table1
join table2 on table1.key = table2.key
GROUP BY $columns;
I am trying to removing duplicate values which, for some reason, was imported in a specific Table.
There is no Primary Key in this table.
There is 27797 unique records.
Select distinct txdate, plunumber from itemaudit
Give me the correct records, but only displays the txdate, plunumber of course.
If it was possible to select all the fields but only select the distinct of txdate,plunumber I could export the values, delete the duplicated ones and re-import.
Or if its possible to delete the distinct values from the entire table.
If you select the distinct of all fields the value is incorrect.
To get all information on the duplicates, you simply need to query all information for the duplicate rows using a JOIN:
SELECT b.*
FROM (SELECT COUNT(*) as cnt, txdate, plunumber
FROM itemaudit
GROUP BY txdate, plunumber
HAVING COUNT(*) > 1) a
INNER JOIN itemaudit b ON a.txdate = b.txdate AND a.plunumber = b.plunumber
DELETE FROM itemaudit t1
WHERE EXISTS (
SELECT 1 FROM itemaudit t2
WHERE t1.txdate = t2.txdate and t1.plunumber = t2.plunumber
AND t1.RDB$DB_KEY < t2.RDB$DB_KEY
);
The query below returns 9,817 records. Now, I want to SELECT one more field from another table. See the 2 lines that are commented out, where I've simply selected this additional field and added a JOIN statement to bind this new columns. With these lines added, the query now returns 649,200 records and I can't figure out why! I guess something is wrong with my WHERE criteria in conjunction with the JOIN statement. Please help, thanks.
SELECT DISTINCT dbo.IMPORT_DOCUMENTS.ITEMID, BEGDOC, BATCHID
--, dbo.CATEGORY_COLLECTION_CATEGORY_RESULTS.CATEGORY_ID
FROM IMPORT_DOCUMENTS
--JOIN dbo.CATEGORY_COLLECTION_CATEGORY_RESULTS ON
dbo.CATEGORY_COLLECTION_CATEGORY_RESULTS.ITEMID = dbo.IMPORT_DOCUMENTS.ITEMID
WHERE (BATCHID LIKE 'IC0%' OR BATCHID LIKE 'LP0%')
AND dbo.IMPORT_DOCUMENTS.ITEMID IN
(SELECT dbo.CATEGORY_COLLECTION_CATEGORY_RESULTS.ITEMID FROM
CATEGORY_COLLECTION_CATEGORY_RESULTS
WHERE SCORE >= .7 AND SCORE <= .75 AND CATEGORY_ID IN(
SELECT CATEGORY_ID FROM CATEGORY_COLLECTION_CATS WHERE COLLECTION_ID IN (11,16))
AND Sample_Id > 0)
AND dbo.IMPORT_DOCUMENTS.ITEMID NOT IN
(SELECT ASSIGNMENT_FOLDER_DOCUMENTS.Item_Id FROM ASSIGNMENT_FOLDER_DOCUMENTS)
One possible reason is because one of your tables contains data at lower level, lower than your join key. For example, there may be multiple records per item id. The same item id is repeated X number of times. I would fix the query like the below. Without data knowledge, Try running the below modified query.... If output is not what you're looking for, convert it into SELECT Within a Select...
Hope this helps....
Try this SQL: SELECT DISTINCT a.ITEMID, a.BEGDOC, a.BATCHID, b.CATEGORY_ID FROM IMPORT_DOCUMENTS a JOIN (SELECT DISTINCT ITEMID FROM CATEGORY_COLLECTION_CATEGORY_RESULTS WHERE SCORE >= .7 AND SCORE <= .75 AND CATEGORY_ID IN (SELECT DISTINCT CATEGORY_ID FROM CATEGORY_COLLECTION_CATS WHERE COLLECTION_ID IN (11,16)) AND Sample_Id > 0) B ON a.ITEMID =b.ITEMID WHERE a.(a.BATCHID LIKE 'IC0%' OR a.BATCHID LIKE 'LP0%') AND a.ITEMID NOT IN (SELECT DIDTINCT Item_Id FROM ASSIGNMENT_FOLDER_DOCUMENTS)