Dont know if i am breaking comuntiy guidelines by posting a continuation question as new question. If so. I am sorry!!
Now, using,
SELECT count(alertid) as cnt,date(alertdate) as alertDate
FROM alertmaster a,subscriptionmaster s
WHERE alertDate BETWEEN DATE_SUB(CURDATE(),INTERVAL 7 DAY) AND CURDATE()
GROUP BY date(alertDate),s.subId
ORDER BY a.alertDate DESC;
produces:
13, '2011-04-08'
13, '2011-04-08'
13, '2011-04-08'
14, '2011-04-07'
13, '2011-04-07'
Where I want is:
39, '2011-04-08'
27, '2011-04-07'
How to achieve this?
The reason you are getting more than one row per date is because you have GROUP BY date(alertDate),s.subId. Just change your GROUP BY to
GROUP BY date(alertDate)
If you don't actually want separate groups for each s.subId,date combination.
Also the code you posted is missing a JOIN condition. This is one reason why using the explicit (ANSI 92) JOIN syntax is preferred.
Related
I do a MySql query that looks for results in two different tables.
Tables
Contract
id, contract, creditor_id, client_id, event_id
Invoice
id, contract_id, invoice, due, value
The idea is to select the contracts using some parameters in the query, such as:
initial delay and final, initial value and final, events, creditor.
For this, I use the INNER JOIN, HAVING and IN.
Details:
After receiving the result, I take the values and loop to make an update on each query result, using the result ID.
I built an example in SQL Fiddle for better visualization.
The problem is, when I do this query with very long results or thousands of lines, the query is really slow.
So, I wanted to know if there is a better way to do the same query in an optimal way.
Query:
SELECT `c`.`id`,
`c`.`contract`,
`c`.`creditor_id`,
`c`.`client_id`,
`c`.`event_id`,
`t`.`total_value`,
`delay`
FROM `contract` `c`
INNER JOIN
(SELECT contract_id,
Sum(value) total_value,
Datediff(Curdate(), due) AS delay
FROM invoice t GROUP BY contract_id
HAVING delay <= 99999
AND delay >= 1
AND total_value >= 1
AND total_value < 99999) t ON `t`.`contract_id` = `c`.`id`
WHERE `c`.`creditor_id` = 1
AND `c`.`event_id` IN(4, 7, 5, 8, 13, 3, 6, 15, 2, 24, 1, 21, 20, 14, 17, 18, 16, 23, 25, 22, 9, 10, 26, 12, 19, 11)
If "1..99999" means "any value", then remove the test from the query. That is construct a different query when the user wants an open-ended test.
Deal with the lack of due in the GROUP BY.
Change Datediff(Curdate(), due) > 123 to due < CURDATE() - INTERVAL 123 DAY. That will give us a chance to use due in an INDEX.
Qualify due and value; we can't tell which table they are in.
Please provide SHOW CREATE TABLE.
c could use INDEX(creditor_id, event_id), but after the above issues are addressed, there may be an even better index.
I'm trying to select only specific hours from my table that contain "Datetime" and other variables.
Example 1:
select distinct(Datetime) from NWP_OUT where HOUR(Datetime) = '00';
this works but when i try to select not only '00' no luck and no result
Example 2:
select distinct(Datetime) from NWP_OUT where HOUR(Datetime) = '00' and '06';
only show the first
I tried using 'between' but then i got 02,04,and 05
My end goal is to select only the data for hours: '00,03,06,09,12,18,21'
it is 10 years of data so manual selection will be hard.
Thank you all in advance!
Use IN:
SELECT DISTINCT(datetime)
FROM NWP_OUT
WHERE HOUR(datetime) IN (0, 3, 6, 9, 12, 18, 21)
You want to use IN
SELECT
DISTINCT(Datetime)
FROM
NWP_OUT
WHERE
HOUR(Datetime) IN ('00','03','06','09','12','18','21')
I am still relatively new to MySQL and am stuck on a bit of data engineering.
I have a table with following:
Event_ID, Minutes, EventCode
I have multiple rows with same Event_ID and what event has occurred (eventcode) along with when in minutes (Minutes).
What I want to do is output to a new table the sequence of events based on the minutes for an event_id:
Eg:
Source:
Event_ID, Minutes, EventCode
12, 45, A
12, 49, B
12, 78, A
WOuld be transformed into:
12, 45, A, 1
12, 49, B, 2
12, 78, B, 3
So the last column shows the sequence. Although it can be assmed the source table is sorted by event_id following by minutes I would rather a solution that worked for it to be unsorted if possible
Some pointers would be great!
Thanks
Im MySQL 8 and higher you can use the row_number() window function.
SELECT event_id,
minutes,
eventcode,
row_number() OVER (PARTITION BY event_id
ORDER BY minutes)
FROM elbat;
Try this query:
select event_id, minutes, eventcode, #rownum:=#rownum+1 No from elbat, (SELECT #rownum:=0) r;
So I am trying to calculate overview statistics into JSON, but am having trouble wrangling them into a query.
There are 2 tables:
appointments
- time timestamp
- patients int
assignments
- user_id int
- appointment_id int
I want to calculate the number of patients by user, by hour for the day. Ideally, it would look like this:
[
{hour: "2015-07-01T08:00:00.000Z", assignments: [
{user_id: 123, patients: 3},
{user_id: 456, patients: 10},
{user_id: 789, patients: 4},
]},
{hour: "2015-07-01T09:00:00.000Z", assignments: [
{user_id: 456, patients: 1},
{user_id: 789, patients: 6}
]},
{hour: "2015-07-01T10:00:00.000Z", assignments: []}
...
]
I got kind of close:
with assignments_totals as (
select user_id,sum(patients),date_trunc('hour',appointments.time) as hour
from assignments
inner join appointments on appointments.id = assignments.appointment_id
group by date_trunc('hour',sales.time),user_id
), hours as (
select to_char(date_trunc('hour',time),'YYYY-MM-DD"T"HH24:00:00.000Z') as hour, array_to_json(array_agg(DISTINCT assignment_totals)) as patients
from appointments
left join assignment_totals on date_trunc('hour',sales.time) = assignment_totals.hour
where time >= '2015-07-01T07:00:00.000Z' and time < '2015-07-02T07:00:00.000Z'
group by date_trunc('hour',time)
order by date_trunc('hour',time)
)
select array_to_json(array_agg(hours)) as hours from hours;
Which outputs:
[
{hour: "2015-07-01T08:00:00.000Z", assignments: [
{user_id: 123, patients: 3, hour: "2015-07-01T08:00:00.000Z" },
{user_id: 456, patients: 10, hour: "2015-07-01T08:00:00.000Z"},
{user_id: 789, patients: 4, hour: "2015-07-01T08:00:00.000Z"},
]},
{hour: "2015-07-01T09:00:00.000Z", assignments: [
{user_id: 456, patients: 1, hour: "2015-07-01T09:00:00.000Z"},
{user_id: 789, patients: 6, hour: "2015-07-01T09:00:00.000Z"}
]},
{hour: "2015-07-01T10:00:00.000Z", assignments: [null]}
...
]
While this works, there are 2 issues, which may or may not be independent of each other:
If there are no appointments that hour, I still want the hour to be included in the array (like 10AM in the example), but to have an empty "assignments" array. Right now it puts a null in there, and I can't figure out how to get rid of it while still keeping the hours in there.
I have to have the hour included in the assignments entries along with user_id and appointments because I need it to join the assignments_totals query to the hours query. But it's unnecessary because it's already in the parent.
I feel like it should be able to be done in 1 cte and 1 query and now I'm using 2 cte's... but can't figure out how to condense it and make it work.
I wanted to do something like
hours as (
select to_char(date_trunc('hour',time),'YYYY-MM-DD"T"HH24:00:00.000Z') as hour, sum(appointments.patients) OVER(partition by assignments.user_id) as appointments
from appointments
left join assignments on appointments.id = assignments.appointment_id
where time >= '2015-07-01T07:00:00.000Z' and time < '2015-07-02T07:00:00.000Z'
group by date_trunc('hour',time)
order by date_trunc('hour',time)
)
select array_to_json(array_agg(hours)) as hours from hours
but i can't get it to work without giving me a "attribute must be in the group by or aggregate function error.
Anyone know how to fix any of these issues? Thanks in advance!
The main issue with your last query seems to be in conflating window functions with aggregate functions. Window functions use the OVER syntax, and they do not in themselves require GROUP BY when there are other fields in the SELECT clause. Aggregate functions, on the other hand, use GROUP BY when there are other (non-aggregate-function) fields in the SELECT clause. One practical consequence of this difference is that window functions are not automatically DISTINCT.
The issue with NULL values resulting from the window function can be resolved with a simple COALESCE such that zero is used instead of null.
So, to write your query using a window function, use something like:
WITH hours AS
(
SELECT DISTINCT to_char(date_trunc('hour', ap.time), 'YYYY-MM-DD"T"HH:00:00.000Z') AS hour,
COALESCE(SUM(ap.patients) OVER (PARTITION BY asgn.user_id), 0) AS appointment_count
FROM appointments ap
LEFT JOIN assignments asgn ON ap.id = asgn.appointment_id
WHERE ap.time >= '2015-07-01T07:00:00.000Z'
AND ap.time < '2015-07-02T07:00:00.000Z'
)
SELECT array_to_json(array_agg(hours)) AS hours
FROM hours
ORDER BY hour
With an aggregate function:
WITH hours AS
(
SELECT to_char(date_trunc('hour', ap.time), 'YYYY-MM-DD"T"HH:00:00.000Z') AS hour,
SUM(COALESCE(ap.patients, 0)) AS appointment_count,
asgn.user_id
FROM appointments ap
LEFT JOIN assignments asgn ON ap.id = asgn.appointment_id
WHERE ap.time >= '2015-07-01T07:00:00.000Z'
AND ap.time < '2015-07-02T07:00:00.000Z'
GROUP BY asgn.user_id, to_char(date_trunc('hour', ap.time), 'YYYY-MM-DD"T"HH:00:00.000Z')
)
SELECT array_to_json(array_agg(hours)) AS hours
FROM hours
ORDER BY hour
My syntax may not be quite correct, so double-check before using this solution or one like it (and feel free to edit to correct any errors).
Most of my frustration with this came because I was not looking at the Postgres 9.4 documentation, which has new functions for dealing with json.
The solution I found builds upon the original query, but then breaks the assignments array down using json_array_elements, filters using where, then builds it back up again. It seems pointless to have essentially:
json_agg(json_array_elements(json_agg(*)))
But it makes very little performance difference and gets me where I need to go. Feel free to comment if you find a better solution! It should also be possible in <9.4 using array_agg and unnest but I was having trouble because I was trying to unnest a record type returned from my CTE, instead of an actual row type with column definitions.
with assignment_totals as (
select
date_trunc('hour',appointments.time) as hour,
user_id,
coalesce(sum(patients),0) as patients
from appointments
left outer join assignments on appointment.id = assignments.appointment_id
where time >= '2015-07-01T07:00:00.000Z' and time < '2015-07-02T07:00:00.000Z'
group by date_trunc('hour',appointments.time),user_id
), hours as (
select
to_char(assignment_totals.hour,'YYYY-MM-DD"T"HH24:00:00.000Z') as hour,
(
select coalesce(json_agg(json_build_object('user_id',(t->'user_id'),'patients',(t->'patients')) order by (t->>'user_id')),'[]'::json)
from json_array_elements(json_agg(assignment_totals)) t
where (t->>'patients') != '0'
) as patients
from assignment_totals
group by assignment_totals.hour
order by assignment_totals.hour
)
select array_to_json(array_agg(hours)) as hours from hours
Thanks to Andrew for pointing out that I can coalesce nulls to 0. But I still want to filter out entries where patients = 0. This solves all my problems by giving me the ability to filter them out with a where, and then gives me the ability to take out the time by building a new json object with json_build_object.
I have few tables
table201202
table201203
table201204
table201205
...
tableversion
In tableversion I have columns:
Version_ID Admin_ID MONTH YEAR
I need to get something like this
Select *
FROM tableversion
LEFT JOIN table(tableversion.month tableversion.year) on
table(tableversion.month tableversion.year).Version_ID=tableversion.version_id
But in tableversion I've got months without leading 0 so i must check if there is 5 and then change it to 05, if variable is 12 then nothing. How can I do it?
Ok, so now i have something like this
SELECT *, CONCAT('table',IF(tableversion.month < 10, CONCAT('0', tableversion.month ), tableversion.month ),year) as year
FROM tableversion
LEFT JOIN year ON tableversion.version_id=year.version_id WHERE ADMIN_ID=11
#1146 - Table 'database.year' doesn't exist
But it does not work
As seen here, use LPAD:
SELECT LPAD(month,2,'0') ...
Try this out in the area where you're concerned about comparing the months
IF(tableversion.month < 10, CONCAT('0', tableversion.month), tableversion.month)
I think an IF statement would likely perform poorly, but I have no data to back that claim.
You can try this alternative to an IF statement to achieve the same:
SELECT *, LPAD(month, 2, '0') as month2 ....