I'm trying to run count query on a 2 table join. e_amazing_client table is having million entries/rows and m_user has just 50 rows BUT count query is taking forever!
SELECT COUNT(`e`.`id`) AS `count`
FROM `e_amazing_client` AS `e`
LEFT JOIN `user` AS `u` ON `e`.`cx_hc_user_id` = `u`.`id`
WHERE ((`e`.`date_created` >= '2018-11-11') AND (`e`.`date_created` >= '2018-11-18')) AND (`e`.`id` >= 1)
I don't know what is wrong with this query?
First, I'm guessing that this is sufficient:
SELECT COUNT(*) AS `count`
FROM e_amazing_client e
WHERE e.date_created >= '2018-11-11' AND e.id >= 1;
If user has only 50 rows, I doubt it is creating duplicates. The comparisons on date_created are redundant.
For this query, try creating an index on e_amazing_client(date_created, id).
Maybe you wanted this:
SELECT COUNT(`e`.`id`) AS `count`
FROM `e_amazing_client` AS `e`
LEFT JOIN `user` AS `u` ON `e`.`cx_hc_user_id` = `u`.`id`
WHERE ((`e`.`date_created` >= '2018-11-11') AND (`e`.`date_created` <= '2018-11-18')) AND (`e`.`id` >= 1)
to check between dates?
Also, do you really need
AND (`e`.`id` >= 1)
If id is what an id is usually in a table, is there a case to be <1?
Your query is pulling ALL records on/after 2018-11-11 because your WHERE clause is ID >= 1 You have no clause in there for a specific user. You also had in your original query based on a date of >= 2018-11-18. You MAY have meant you only wanted the count WITHIN the week 11/11 to 11/18 where the sign SHOULD have been >= 11-11 and <= 11-18.
As for the count, you are getting ALL people (assuming no entry has an ID less than 1) and thus a count within that date range. If you want it per user as you indicated you need to group by the cx_hc_user_id (user) column to see who has the most, or make the user part of the WHERE clause to get one person.
SELECT
e.cx_hc_user_id,
count(*) countPerUser
from
e_amazing_client e
WHERE
e.date_created >= '2018-11-11'
AND e.date_created <= '2018-11-18'
group by
e.cx_hc_user_id
You can order by the count descending to get the user with the highest count, but still not positive what you are asking.
Related
I am trying to join two tables
ad_data_grouped
adID, adDate (date), totalViews
This is data that has already been grouped by both adID and adDate.
The second table is
leads
leadID, DateOfBirth, adID, state, createdAt(dateTime)
What I'm struggling with is joining these two tables so I can have a column that counts the number of leads when it shares the same adID and where the adDate = createdAt
The problem I'm running into is that when the counts are all the same for all groupings of adID....I have a few other things I'm trying to do, but it's based on similar similar conditional counting.
Query:(I know the temp table is probably overkill, but I'm trying to break this up into small pieces where I can understand what each piece does)
CREATE TEMPORARY TABLE ad_stats_grouped
SELECT * FROM `ad_stats`
LIMIT 0;
INSERT INTO ad_stats_grouped(AdID, adDate, DailyViews)
SELECT
AdID,
adDate,
sum(DailyViews)
FROM `ad_stats`
GROUP BY adID, adDate;
SELECT
ad_stats_grouped.adID,
ad_stats_grouped.adDate,
COUNT(case when ad_stats_grouped.adDate = Date(Leads.CreatedAt) THEN 1 ELSE 0 END)
FROM `ad_stats_grouped` INNER JOIN `LEADS` ON
ad_stats_grouped.adID = Leads.AdID
GROUP BY adID, adDate;
The problem with your original query is the logic in the COUNT(). This aggregate functions takes in account all non-null values, so it counts 0 and 1s. One solution would be to change COUNT() to SUM().
But I think that the query can be furtermore improved by moving the date condition on the date to the on part of a left join:
select
g.adid,
g.addate,
count(l.adid)
from `ad_stats_grouped` g
left join `leads` l
on g.adid = l.adid
and l.createdat >= g.addate
and l.createdat < g.ad_stats + interval 1 day
group by g.adid, g.addate;
I have a MySQL table which stores the data of a hotel's reservations.
I need a query to see the amount of guests who stayed in the hotel for each date.
I was able to create a query (using a subquery) but it performs very slowly. Is there a better way to get the requested data? (For example join the table to itself, or whatever.)
My query is:
SELECT CheckOutDate AS Date,
(SELECT SUM(NrOfGuests) FROM tblGuests tG
WHERE tG.CheckInDate <= tblGuests.CheckOutDate
AND tG.CheckOutDate > tblGuests.CheckOutDate
AND tG.IsCancelled = False AND tG.NoShow = False)
AS NrOfGestsStaying
FROM tblGuests
GROUP BY CheckOutDate
What is the best way to make it perform faster?
In the original query, the SELECT returns a SUM on every row of the table using a subquery. The duplicates are removed afterwards using a group by CheckOutDate. So, in other words, this is the SUM(NrOfGuests) for distinct CheckOutDate.
You can remove duplicate CheckOutDate in advance by subquerying distinct CheckOutDate. So in the receiving query the SUM is applied just one time for distinct CheckOutDate:
SELECT dT.CheckOutDate
,(SELECT SUM(NrOfGuests)
FROM tblGuests tG
WHERE tG.CheckInDate <= dT.CheckOutDate
AND tG.CheckOutDate >= dT.CheckOutDate
AND tG.IsCancelled = 0
AND tG.NoShow = 0
) AS NrOfGuests
FROM (
SELECT DISTINCT CheckOutDate
FROM tblGuests
) AS dT
ORDER BY dT.CheckOutDate
I have a table where I am storing the stored number of barrels inside of many tanks. I am storing values here every night at midnight, and at the beggining and end of any operator initiated transfer.
What I want to return is the number of barrels difference since the previous event record for that specific tank. I have the correct ID for the self join to get the previous record number, however the barrels is incorrect.
Here is what I currently have.
SELECT
inventory.id,
MAX(inventory2.id) AS id2,
inventory.tankname,
inventory.barrels,
inventory.eventstamp,
inventory2.barrels
FROM
inventory
LEFT JOIN
inventory inventory2 ON inventory2.tankname = inventory.tankname AND inventory2.eventstamp < inventory.eventstamp
GROUP BY
inventory.id,
inventory.tankname,
inventory.barrels,
inventory.eventstamp
ORDER BY
inventory.tankname,
inventory.eventstamp
That returns the following
Just use correlated subqueries:
SELECT i.*,
(SELECT i2.id
FROM inventory i2
WHERE i2.tankname = i.tankname AND
i2.eventstamp < i.eventstamp
ORDER BY i2.eventstamp DESC
LIMIT 1
) as prev_id,
(SELECT i2.barrels
FROM inventory i2
WHERE i2.tankname = i.tankname AND
i2.eventstamp < i.eventstamp
ORDER BY i2.eventstamp DESC
LIMIT 1
) as prev_barrels
FROM inventory i
ORDER BY i.tankname, i.eventstamp;
Your query doesn't work because you have columns in the SELECT that are not in the GROUP BY and are not aggregated. That shouldn't be allowed in any database; it is unfortunate that MySQL does allow it.
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 have a table which contains all orders, i'm trying to separate orders by hour.
if there is no record for an specific hour, the query will ignore that hour, but what i'm trying to achieve is to report'0' for that hour.
I also joined the table with a temporary table containing all hours.
SELECT sum(orders.price), hour(orders.time) as hour
FROM orders
RIGHT JOIN dummy_time as dummy
ON hour(orders.time) = dummy.time
WHERE state = 1
AND (date(orders.time) = '2014-06-17' or orders.time is null)
GROUP BY hour
You can view my query in SQLFiddle
To get all rows from dummy_time, move your conditions from your WHERE to your RIGHT JOIN. Also, select the hour from dummy.time so you will get all hours.
Use COALESCE to get values of 0 where an order doesn't have records.
SELECT COALESCE(sum(orders.price),0), dummy.time as hour
FROM orders
RIGHT JOIN dummy_time as dummy
ON hour(orders.time) = dummy.time
AND orders.state = 1
AND orders.time BETWEEN '2014-06-17 00:00:00' AND '2014-06-17 23:59:59'
GROUP BY dummy.time
http://www.sqlfiddle.com/#!2/c7adb/2
The query plan for the query below looks worse than the one above but because you reported that the JOIN seems to be the main source of slowness it's worth a try. The query below reduces the set of rows before doing a JOIN.
SELECT
COALESCE(t1.orders_sum,0),
t2.time
FROM
(
SELECT
sum(orders.price) orders_sum,
hour(orders.time) orders_hour
FROM orders
WHERE orders.state = 1
AND orders.time BETWEEN '2014-06-17 00:00:00' AND '2014-06-17 23:59:59'
GROUP BY hour(orders.time)
) t1 RIGHT JOIN dummy_time t2 ON t1.orders_hour = t2.time
http://www.sqlfiddle.com/#!2/0775b/1
Also, make sure your tables are indexed
CREATE INDEX test_index1 ON orders (state,time);
CREATE INDEX test_index2 ON dummy_time (time);
Is this what you are looking for? It uses a case for when state=1 versus state=0 on whether to display sum orders or whether to display 0. If not please let me know your desired result.