I'm just starting to learn SQL, and managed to cobble together a couple of working queries, but then when I combine them I am getting a syntax error. The query throwing the error:
SELECT sca_ticket_status.name As Status, AVG(QueueTime)
FROM (SELECT DateDiff (created, now()) as 'QueueTime'
FROM sca_ticket as SubQuery
LEFT JOIN sca_ticket_status
ON sca_ticket.status_id = sca_ticket_status.id
GROUP BY name
ORDER BY sort
For reference, the two working queries that I am attempting to leverage are as follows:
SELECT sca_ticket_status.name As Status, COUNT(sca_ticket.ticket_id) AS Count
FROM sca_ticket
LEFT JOIN sca_ticket_status
ON sca_ticket.status_id = sca_ticket_status.id
WHERE sca_ticket.created between date_sub(now(),INTERVAL 1 WEEK) and now()
GROUP BY name
ORDER BY sort
SELECT AVG(QueueTime)
FROM (SELECT DateDiff (created, now()) as 'QueueTime'
FROM `sca_ticket`
WHERE `status_id` = 1) as SubQuery
Try closing your second select statement
SELECT sca_ticket_status.name As Status, AVG(QueueTime)
FROM (SELECT status_id, DateDiff (created, now()) as 'QueueTime'
FROM sca_ticket) q1
LEFT JOIN sca_ticket_status
ON q1.status_id = sca_ticket_status.id
GROUP BY name
ORDER BY sort
You will also need to expose the status_id column in your inner select list if you want to join on it later.
You do not need a subquery at all. This just slows down the processing in MySQL (the optimizer is not very smart; it materializes subqueries losing index information).
SELECT ts.name As Status, AVG(DateDiff(t.created, now()))
FROM sca_ticket t LEFT JOIN
sca_ticket_status ts
ON t.status_id = ts.id
GROUP BY ts.name
ORDER BY sort
Related
I am trying to produce a result that shows duplicates in a table. One method I found for getting duplicates and showing them is to run the select statement again through an inner join. However, one of my columns needs to be the result of a function, and the only thing I can think to do is use an alias, however I can't use the alias twice in a SELECT statement.
I am not sure what the best way to run this code for getting the duplicates I need.
My code below
SELECT EXTRACT(YEAR_MONTH FROM date) as 'ndate', a.transponderID
FROM dispondo_prod_disposition.event a
inner JOIN (SELECT EXTRACT(YEAR_MONTH FROM date) as ???,
transponderID, COUNT(*)
FROM dispondo_prod_disposition.event
GROUP BY mdate, transponderID
HAVING count(*) > 1 ) b
ON ndate = ???
AND a.transponderID = b.transponderID
ORDER BY b.transponderID
SELECT b.ndate, transponderID
FROM dispondo_prod_disposition.event a
INNER JOIN ( SELECT EXTRACT(YEAR_MONTH FROM date) as ndate,
transponderID
FROM dispondo_prod_disposition.event
GROUP BY 1, 2
HAVING COUNT(*) > 1 ) b USING (transponderID)
WHERE b.ndate = ??? -- for example, WHERE b.ndate = 202201
ORDER BY transponderID
This question already has an answer here:
ERROR 1111 (HY000): Invalid use of group function
(1 answer)
Closed 1 year ago.
I'm not yet good at MySQL. Please check my sql below and help me understand where I went wrong with it. All I need is just one record for the order.id and the returned record must be the one whose shipped date is the latest.
Database error: Invalid SQL: SELECT orders.id, orders.customer_fk FROM orders INNER JOIN order_details ON order_details.order_fk=orders.id WHERE orders.payment_method IN ('AS','AC') AND ((orders.order_status='SHP' AND order_details.item_status='SHP' AND MAX(order_details.shipped_date) <= '2021-08-07') OR (orders.order_status='CAN' AND orders.order_date <= '2021-08-07 09:56:18')) AND orders.pii_status <> '1'GROUP BY orders.id
MySQL Error: 1111 (Invalid use of group function)
Instead of using MAX alone try to use a subselect
If you don't want the mad for every order.id then you need to add a inner join
SELECT
orders.id, orders.customer_fk
FROM
orders
INNER JOIN
order_details ON order_details.order_fk = orders.id
WHERE
orders.payment_method IN ('AS' , 'AC')
AND ((orders.order_status = 'SHP'
AND order_details.item_status = 'SHP'
AND (SELECT MAX(shipped_date) FROM order_details WHERE order_fk = orders.id) <= '2021-08-07')
OR (orders.order_status = 'CAN'
AND orders.order_date <= '2021-08-07 09:56:18'))
AND orders.pii_status <> '1'
GROUP BY orders.id
To explain it somewhat further
SELECT MAX(shipped_date) FROM order_details WHERE order_fk = orders.id) <= '2021-08-07'
Return true or false for every Order.id as it checks for every row in the outer select what the maximum date is and then checks it against the date.
After selecting all rows you GROUP BY(which i still don't get as you have no aggregation function it) comes for every order.id.
Maybe you should try a DISTINCT
You select both orders.id and orders.customer_fk, but you group by orders.id only. When using group by in SQL, all other columns not present in the group by clause must be aggregate functions, since for example in this current case you group the results by the order id, meaning there can be only one row per unique order id among the results.
And something has to happen with the list of values of the other column that all belong to this one grouped order id, this is where the aggregations come in. If it is a number you can calculate the MIN/MAX/AVG etc. of these, but the simplest aggregate is to just count the matching results.
So if you wanted your query to return the number of order.customer_fk for each unique order.id, just add SELECT orders.id, COUNT(orders.customer_fk).
Otherwise, if you didn't intend to group your results, you can remove the GROUP BY clause, or replace it with an ORDER BY.
If you want to filter using aggregation functions use having. However, I'm guessing that you just want to filter by the date:
SELECT o.id, o.customer_fk
FROM orders o INNER JOIN
order_details od
ON od.order_fk= o.id
WHERE o.payment_method IN ('AS','AC') AND
((o.order_status = 'SHP' AND od.item_status='SHP' AND od.shipped_date <= '2021-08-07') OR
(o.order_status = 'CAN' AND o.order_date <= '2021-08-07 09:56:18')
) AND
o.pii_status <> '1'
GROUP BY o.id
I have SQL query with LEFT JOIN:
SELECT COUNT(stn.stocksId) AS count_stocks
FROM MedicalFacilities AS a
LEFT JOIN stocks stn ON
(stn.stocksIdMF = ( SELECT b.MedicalFacilitiesIdUser
FROM medicalfacilities AS b
WHERE b.MedicalFacilitiesIdUser = a.MedicalFacilitiesIdUser
ORDER BY stn.stocksId DESC LIMIT 1)
AND stn.stocksEndDate >= UNIX_TIMESTAMP() AND stn.stocksStartDate <= UNIX_TIMESTAMP())
These query I want to select one row from table stocks by conditions and with field equal value a.MedicalFacilitiesIdUser.
I get always count_stocks = 0 in result. But I need to get 1
The count(...) aggregate doesn't count null, so its argument matters:
COUNT(stn.stocksId)
Since stn is your right hand table, this will not count anything if the left join misses. You could use:
COUNT(*)
which counts every row, even if all its columns are null. Or a column from the left hand table (a) that is never null:
COUNT(a.ID)
Your subquery in the on looks very strange to me:
on stn.stocksIdMF = ( SELECT b.MedicalFacilitiesIdUser
FROM medicalfacilities AS b
WHERE b.MedicalFacilitiesIdUser = a.MedicalFacilitiesIdUser
ORDER BY stn.stocksId DESC LIMIT 1)
This is comparing MedicalFacilitiesIdUser to stocksIdMF. Admittedly, you have no sample data or data layouts, but the naming of the columns suggests that these are not the same thing. Perhaps you intend:
on stn.stocksIdMF = ( SELECT b.stocksId
-----------------------------^
FROM medicalfacilities AS b
WHERE b.MedicalFacilitiesIdUser = a.MedicalFacilitiesIdUser
ORDER BY b.stocksId DESC
LIMIT 1)
Also, ordering by stn.stocksid wouldn't do anything useful, because that would be coming from outside the subquery.
Your subquery seems redundant and main query is hard to read as much of the join statements could be placed in where clause. Additionally, original query might have a performance issue.
Recall WHERE is an implicit join and JOIN is an explicit join. Query optimizers
make no distinction between the two if they use same expressions but readability and maintainability is another thing to acknowledge.
Consider the revised version (notice I added a GROUP BY):
SELECT COUNT(stn.stocksId) AS count_stocks
FROM MedicalFacilities AS a
LEFT JOIN stocks stn ON stn.stocksIdMF = a.MedicalFacilitiesIdUser
WHERE stn.stocksEndDate >= UNIX_TIMESTAMP()
AND stn.stocksStartDate <= UNIX_TIMESTAMP()
GROUP BY stn.stocksId
ORDER BY stn.stocksId DESC
LIMIT 1
There are 3 tables, persontbl1, persontbl2 (each 7500 rows) and schedule (~3000 active schedules i.e. schedule.status = 0). Person tables contain data for the same persons as one to one relationship and INNER join between two takes less than a second. And schedule table contains data about persons to be interviewed and not all persons have schedules in schedule table. With Left join query instantly takes around 45 seconds, which is causing all sorts of issues.
SELECT persontbl1._CREATION_DATE, persontbl2._TOP_LEVEL_AURI,
persontbl2.RESP_CNIC, persontbl2.RESP_CNIC_NAME,
persontbl1.MOB_NUMBER1, persontbl1.MOB_NUMBER2,
schedule.id, schedule.call_datetime, schedule.enum_id,
schedule.enum_change, schedule.status
FROM persontbl1
INNER JOIN persontbl2 ON (persontbl2._TOP_LEVEL_AURI = persontbl1._URI)
AND (AGR_CONTACT=1)
LEFT JOIN SCHEDULE ON (schedule.survey_id = persontbl1._URI)
AND (SCHEDULE.status=0)
AND (DATE(SCHEDULE.call_datetime) <= CURDATE())
ORDER BY schedule.call_datetime IS NULL DESC, persontbl1._CREATION_DATE ASC
Here is the explain for query:
Schedule Table structure:
Schedule Table indexes:
Please let me know if any further information is required.
Thanks.
Edit: Added fully qualified table names and their columns.
You should just replace this line:
AND (DATE(SCHEDULE.call_datetime) <= CURDATE())
to this one:
AND SCHEDULE.call_datetime <= '2015-04-18 00:00:00'
so mysql will not call 2 functions per every record but will use static constant '2015-04-18 00:00:00'.
So you can just try for performance improvements if your query is:
SELECT persontbl1._CREATION_DATE, persontbl2._TOP_LEVEL_AURI,
persontbl2.RESP_CNIC, persontbl2.RESP_CNIC_NAME,
persontbl1.MOB_NUMBER1, persontbl1.MOB_NUMBER2,
schedule.id, schedule.call_datetime, schedule.enum_id,
schedule.enum_change, schedule.status
FROM persontbl1
INNER JOIN persontbl2 ON (persontbl2._TOP_LEVEL_AURI = persontbl1._URI)
AND (AGR_CONTACT=1)
LEFT JOIN SCHEDULE ON (schedule.survey_id = persontbl1._URI)
AND (SCHEDULE.status=0)
AND (SCHEDULE.call_datetime <= '2015-02-01 00:00:00')
ORDER BY schedule.call_datetime IS NULL DESC, persontbl1._CREATION_DATE ASC
EDIT 1 So you said without LEFT JOIN part it was fast enough, so you can try then:
SELECT persontbl1._CREATION_DATE, persontbl2._TOP_LEVEL_AURI,
persontbl2.RESP_CNIC, persontbl2.RESP_CNIC_NAME,
persontbl1.MOB_NUMBER1, persontbl1.MOB_NUMBER2,
s.id, s.call_datetime, s.enum_id,
s.enum_change, s.status
FROM persontbl1
INNER JOIN persontbl2 ON (persontbl2._TOP_LEVEL_AURI = persontbl1._URI)
AND (AGR_CONTACT=1)
LEFT JOIN
(SELECT *
FROM SCHEDULE
WHERE status=0
AND call_datetime <= '2015-02-01 00:00:00'
) s
ON s.survey_id = persontbl1._URI
ORDER BY s.call_datetime IS NULL DESC, persontbl1._CREATION_DATE ASC
I'm guessing that AGR_CONTACT comes from p1. This is the query you want to optimize:
SELECT p1._CREATION_DATE, _TOP_LEVEL_AURI, RESP_CNIC, RESP_CNIC_NAME,
MOB_NUMBER1, MOB_NUMBER2,
s.id, s.call_datetime, s.enum_id, s.enum_change, s.status
FROM persontbl1 p1 INNER JOIN
persontbl2 p2
ON (p2._TOP_LEVEL_AURI = p1._URI) AND (p1.AGR_CONTACT = 1) LEFT JOIN
SCHEDULE s
ON (s.survey_id = p1._URI) AND
(s.status = 0) AND
(DATE(s.call_datetime) <= CURDATE())
ORDER BY s.call_datetime IS NULL DESC, p1._CREATION_DATE ASC;
The best indexes for this query are: persontbl2(agr_contact), persontbl1(_TOP_LEVEL_AURI, _uri), and schedule(survey_id, status, call_datime).
The use of date() around the date time is not recommended. In general, that precludes the use of indexes. However, in this case, you have a left join, so it doesn't make a difference. That column is not being used for filtering anyway. The index on schedule is only for covering the on clause.
I'm not really sure how to do this. I have website that tracks when a server goes down. So I have 1 table with the server names and ID's named servers and another where the error messages are held called errors. I want to return a calendar like view for the past 7 days that would show if an error occurred in any of our servers.
So far, I have a query that will find error messages for that day for any one server, but I don't know how to return the servers that are good and had 0 errors.
SELECT errors.error_id, servers.server_id, errors.start_time, servers.name
FROM errors
INNER JOIN servers ON errors.server_id=servers.server_id
WHERE errors.start_time BETWEEN '2014-02-25 00:00:00' AND '2014-02-25 23:59:59'
I have it loop through the 7 days and that all works. But I'm stuck on how to get the id's and names of the servers that DID NOT go down on that day. I've been thinking about implementing an IF or CASE into the query, but I've never used them before and I'm not quite sure how that would work.
Do I need to run multiple queries for this or is it possible with one?
Instead of looping through the days, do them all at once. Assuming you have at least one error per day, you can get this information from the errors table. Otherwise, you might need a calendar table for this:
SELECT dates.thedate, e.error_id, s.server_id, e.start_time, s.name
FROM (select distinct date(start_time) as thedate
from errors
where e.start_time BETWEEN '2014-02-25 00:00:00' AND '2014-03-03 23:59:59'
) dates cross join
servers s LEFT OUTER JOIN
errors e
ON e.server_id = s.server_id;
This will generate a row for each error for each server per day. If there is no error, there will be a row for each server with NULL in the error fields. If you want to aggregate this:
SELECT dates.thedate, s.server_id, s.name, count(*) as numErrors,
group_concat(error_id order by e.start_time) as errorIds,
group_concat(se.tart_time order by e.start_time) as startTimes
FROM (select distinct date(start_time) as thedate
from errors
where e.start_time BETWEEN '2014-02-25 00:00:00' AND '2014-03-03 23:59:59'
) dates cross join
servers s LEFT OUTER JOIN
errors e
ON e.server_id = s.server_id and date(e.start_time) = dates.thedate
GROUP BY dates.thedate, s.server_id, s.name;
EDIT:
Without a calendar table, you can insert each day into the query like this:
SELECT dates.thedate, s.server_id, s.name, count(*) as numErrors,
group_concat(error_id order by e.start_time) as errorIds,
group_concat(se.tart_time order by e.start_time) as startTimes
FROM (select date('2014-02-25') as thedate union all
select date('2014-02-26') union all
select date('2014-02-27') union all
select date('2014-02-28') union all
select date('2014-03-01') union all
select date('2014-03-02') union all
select date('2014-03-03')
) dates cross join
servers s LEFT OUTER JOIN
errors e
ON e.server_id = s.server_id and date(e.start_time) = dates.thedate
GROUP BY dates.thedate, s.server_id, s.name;