Here's an example of the tables and outputs I want
I want to group by by no reg with condition, status = 0 but if in table activity there is no status = 0 then that will be selected is with biggest id
You may only need this query.
Select no_reg, location from activities where status = 0
Check the result and run another query.
if (result == null){ //for example run the query below
Select no_reg, location from activities desc limit 1
}
From the image what you want is activities of the equipment i believe
for example if you want to check the equipment A1 Malaysia should be list or one with biggest status will be listed i believe
if thats what you want here it is
SELECT no_reg,MAX(status) FROM activities a,equipment e on e.no_reg=a.no_reg where e.no_reg='A1' group by a.no_reg
i believe this is the solution you are expecting
Related
Have a fact table joined with dimension tables to pull out specific information.
I want to pull out id's where the status = running and they must have the running status between several dates.
If between the dates specified, the status changes to other than "running" that campaign is not counted for in the result.
I have an idea of how to approach it, but i don't think my logic and syntax is exactly correct. As I think the query below would pull data for 12345 which is not intended.
iddate
id
status
06-09
12345
running
06-10
12345
running
06-11
12345
ended
06-09
98765
running
06-10
98765
running
06-11
98765
running
The result expected should only show information for id 98765
Current SQL
SELECT
*
From....
Where status='running'
AND iddate BETWEEN DATE('2022-06-09') AND DATE('2022-06-11')
Group by 1,2,3
I believe I am likely missing a "NOT" condition somewhere to further filter out the dates.
Or the other thought is that id must have running between those dates, however, I am not sure how to apply that logic and its syntax. Any help would be appreciated.
you could do a case statement to compare the running count to the total count.
select id,
count('dracula') cnt,
sum(case when status = 'running' then 1 else 0 end) cnt2
from mytable
where iddate BETWEEN DATE('2022-06-09') AND DATE('2022-06-11')
group by id
having cnt = cnt2
here is the fiddle.
https://www.db-fiddle.com/f/fmFcwnGXyovYezBSCQ4aac/0
Instead of selecting those that had status = 'running', you could filter out those that don't have status = 'running', in the specified time frame.
WITH cte AS (
SELECT *
FROM tab
WHERE iddate BETWEEN DATE('2022-06-09') AND DATE('2022-06-11')
)
SELECT DISTINCT id
FROM cte
WHERE id NOT IN (SELECT id FROM cte WHERE NOT status = 'running')
Check the demo here.
I've a table with a structure something like this,
Device | paid | time
abc 1 2 days ago
abc 0 1 day ago
abc 0 5 mins ago
Is it possible to write a query that checks the paid column on all the rows where Device = abc and then outputs the most recent two rows that different. Basically, something like an if statement saying if row 1 = 1 and row 2 = 0 output that but only if it's the most recent two columns that are different. For example, in this case, the first and second row. The table is being updated whenever a user changes from a free to paid account etc. It is also updated in different columns for different reasons hence the duplicate 0s for example.
I know this would probably be done better by having another table altogether and updating that every time the user switches account type, but is there any way to make this work?
Thanks
Example:
http://rextester.com/MABU7860 need further testing on edge cases but this seems to work.
SELECT A.*, B.*
FROM SQLfoo A
INNER JOIN SQLFoo B
on A.Device = B.Device
and A.mTime < B.mTime
WHERE A.Paid <> B.Paid
and A.device = 'abc'
ORDER BY B.mTime Desc, A.MTime Desc
LIMIT 1
By performing a self join we on the devices where the time from one table is less than the time from the next table (thus the two records will never matach and we only get the reuslts one way) and we order by those times descending, the highest times appear first in the result since we limit by a single device we don't need to concern ourselves with the devices. We then just need compare the paid from one source to the paid in the 2nd source and return the first result encountered thus limit 1.
Or using user variables
http://rextester.com/TWVEVX7830
in other engines one might accomplish this task by performing the join as in above, assigning a row number partitioned by the device and then simply return all those row_numbers with a value of 1; which would be the earliest date discrepency.
Use LIMIT to limit the number of record on mysql:
http://www.mysqltutorial.org/mysql-limit.aspx
In your case, use LIMIT 2
and then put the 2 record that you just select into an array, then compare the array if the value is different. If they are different then print
I have a data set like this:
User Date Status
Eric 1/1/2015 4
Eric 2/1/2015 2
Eric 3/1/2015 4
Mike 1/1/2015 4
Mike 2/1/2015 4
Mike 3/1/2015 2
I'm trying to write a query in which I will retrieve users whose MOST RECENT transaction status is a 4. If it's not a 4 I don't want to see that user in the results. This dataset could have 2 potential results, one for Eric and one for Mike. However, Mike's most recent transaction was not a 4, therefore:
The return result would be:
User Date Status
Eric 3/1/2015 4
As this record is the only record for Eric that has a 4 as his latest transaction date.
Here's what I've tried so far:
SELECT
user, MAX(date) as dates, status
FROM
orders
GROUP BY
status,
user
This would get me to a unqiue record for every user for every status type. This would be a subquery, and the parent query would look like:
SELECT
user, dates, status
WHERE
status = 4
GROUP BY
user
However, this is clearly flawed as I don't want status = 4 records IF their most recent record is not a 4. I only want status = 4 when the latest date is a 4. Any thoughts?
SELECT user, date
, actualOrders.status
FROM (
SELECT user, MAX(date) as date
FROM orders
GROUP BY user) AS lastOrderDates
INNER JOIN orders AS actualOrders USING (user, date)
WHERE actualOrders.status = 4
;
-- Since USING is being used, there is not a need to specify source of the
-- user and date fields in the SELECT clause; however, if an ON clause was
-- used instead, either table could be used as the source of those fields.
Also, you may want to rethink the field names used if it is not too late and user and date are both found here.
SELECT user, date, status FROM
(
SELECT user, MAX(date) as date, status FROM orders GROUP BY user
)
WHERE status = 4
The easiest way is to include your order table a second time in a subquery in your from clause in order to retrieve the last date for each user. Then you can add a where clause to match the most recent date per user, and finally filter on the status.
select orders.*
from orders,
(
select ord_user, max(ord_date) ord_date
from orders
group by ord_user
) latestdate
where orders.ord_status = 4
and orders.ord_user = latestdate.ord_user
and orders.ord_date = latestdate.ord_date
Another option is to use the over partition clause:
Oracle SQL query: Retrieve latest values per group based on time
Regards,
I have a table "Log"
My game server inserts a record into this table when someone login the server, then inserts a second record when they logout.
What I want to do is create a query to count the number of people logged in.
the main data that gets inserted to the table "Log"
When they Login:
[Type] = 0
[Player1] = Their account ID
[Value2] = a random number which matches the logout row when they logout
[Value3] = 0
When they Logout:
[Type] = 1
[Player1] = Their account ID
[Value2] = a random number which matches the login row when they logout
[Value3] = some random number
Is there a way I can count the last "Player1" of each account and check if "Type" = 0 which means that account is logged in then echo the result.
The result I'm looking for would pull the last record of every account an count them.
Note: everytime an account logs in and out it inserts them 2 records so if 1 account logs in 20 times there would be 40 records in "Log"
One way to do it is to count all rows with type 0 for which there doesn't exist any type 1 row with the same player and a later date:
select count(*) as number_of_logged_in
from log l
where Type = 0 -- 0 meaning log on event
-- and [Value3] = 0 -- maybe this should be included
and not exists (
select 1 from log
where Player1 = l.Player1
and type = 1 -- 1 meaning log out event
and date > l.date
-- and [Value2] = l.[Value2] -- maybe this should be included
);
I found your problem statement a bit confusing as you say you want to count the number of people that are logged in, but then you say I want to count the last of each [Player!] where [Type] is 1 which seems to be the opposite. It's also not clear to me why the random number would be important - if the last recorded type for a user is 0 then they should be considered as logged in, or?
Sample SQL Fiddle with some demo data
I am assuming you want list of the all the logged in players names,so you can try using the ROW_NUMBER() to get what you want,
;WITH CTE AS(
SELECT
Player1 AS LoggedInPlayer,
ROW_NUMBER() OVER (PARTITION BY Player1 ORDER BY datecolumn Asc) As LoggedValue
FROM
yourtable
)
SELECT
*
FROM
CTE
WHERE
LoggedValue = 1
If you know, that all logins and logouts are stored in Log without gaps, you can simply count them and if there's a difference you know, that the player is currently logged in.
SELECT logins.player1, logouts.cnt - logins.cnt
FROM
(select player1, count(*) as cnt from Log where type = 0 group by player1) as logins
LEFT OUTER JOIN
(select player1, count(*) as cnt from Log where type = 1 group by player1) as logouts
ON (logins.player1 = logouts.player1)
WHERE logins.cnt > logouts.cnt or logouts.player1 is null
You need the left outer join, if the player logged in one time and never logged out. Sorry, if you encounter syntax issues. I just wrote this without testing and usually work on a Teradata System and the SQL Dialect there. But as the SQL given here is plain Ansi, it should work on any database.
I'm getting grey hair by now...
I have a table like this.
ID - Place - Person
1 - London - Anna
2 - Stockholm - Johan
3 - Gothenburg - Anna
4 - London - Nils
And I want to get the result where all the different persons are included, but I want to choose which Place to order by.
For example. I want to get a list where they are ordered by LONDON and the rest will follow, but distinct on PERSON.
Output like this:
ID - Place - Person
1 - London - Anna
4 - London - Nils
2 - Stockholm - Johan
Tried this:
SELECT ID, Person
FROM users
ORDER BY FIELD(Place,'London'), Person ASC "
But it gives me:
ID - Place - Person
1 - London - Anna
4 - London - Nils
3 - Gothenburg - Anna
2 - Stockholm - Johan
And I really dont want Anna, or any person, to be in the result more then once.
This is one way to get the specified output, but this uses MySQL specific behavior which is not guaranteed:
SELECT q.ID
, q.Place
, q.Person
FROM ( SELECT IF(p.Person<=>#prev_person,0,1) AS r
, #prev_person := p.Person AS person
, p.Place
, p.ID
FROM users p
CROSS
JOIN (SELECT #prev_person := NULL) i
ORDER BY p.Person, !(p.Place<=>'London'), p.ID
) q
WHERE q.r = 1
ORDER BY !(q.Place<=>'London'), q.Person
This query uses an inline view to return all the rows in a particular order, by Person, so that all of the 'Anna' rows are together, followed by all the 'Johan' rows, etc. The set of rows for each person is ordered by, Place='London' first, then by ID.
The "trick" is to use a MySQL user variable to compare the values from the current row with values from the previous row. In this example, we're checking if the 'Person' on the current row is the same as the 'Person' on the previous row. Based on that check, we return a 1 if this is the "first" row we're processing for a a person, otherwise we return a 0.
The outermost query processes the rows from the inline view, and excludes all but the "first" row for each Person (the 0 or 1 we returned from the inline view.)
(This isn't the only way to get the resultset. But this is one way of emulating analytic functions which are available in other RDBMS.)
For comparison, in databases other than MySQL, we could use SQL something like this:
SELECT ROW_NUMBER() OVER (PARTITION BY t.Person ORDER BY
CASE WHEN t.Place='London' THEN 0 ELSE 1 END, t.ID) AS rn
, t.ID
, t.Place
, t.Person
FROM users t
WHERE rn=1
ORDER BY CASE WHEN t.Place='London' THEN 0 ELSE 1 END, t.Person
Followup
At the beginning of the answer, I referred to MySQL behavior that was not guaranteed. I was referring to the usage of MySQL User-Defined variables within a SQL statement.
Excerpts from MySQL 5.5 Reference Manual http://dev.mysql.com/doc/refman/5.5/en/user-variables.html
"As a general rule, other than in SET statements, you should never assign a value to a user variable and read the value within the same statement."
"For other statements, such as SELECT, you might get the results you expect, but this is not guaranteed."
"the order of evaluation for expressions involving user variables is undefined."
Try this:
SELECT ID, Place, Person
FROM users
GROUP BY Person
ORDER BY FIELD(Place,'London') DESC, Person ASC;
You want to use group by instead of distinct:
SELECT ID, Person
FROM users
GROUP BY ID, Person
ORDER BY MAX(FIELD(Place, 'London')), Person ASC;
The GROUP BY does the same thing as SELECT DISTINCT. But, you are allowed to mention other fields in clauses such as HAVING and ORDER BY.