Trying to . convert a value to a name during output - postgresql

the values returned in column a.user_id are id numbers. I would like to return them as a name or initials e.g. 1 = Chris O or C.ONeill
I have tried CASE function but did not know where to put it
SELECT DISTINCT
sb.start_time::date AS shift_date,
i.title AS industry,
wl.name AS venue_name,
w.first_name,
w.last_name,
MIN(cs.start_time::date) AS first_completed_shift,
i.title AS industry,
w.interviewed_on AS induction_date,
d.issue_date AS edbs_issue_date,
d.created_at AS date_dbs_added,
a.user_id --IS IT POSSIBLE TO GET THESE AS VALUES,e.g. a.user_id '1' = 'Chris O or C.ONeill' USING USER NAMES INSTEAD OF USER ID?
FROM shift_bookings sb
JOIN jobs j ON sb.job_id = j.id
JOIN listings l ON j.listing_id = l.id
JOIN work_locations wl ON l.venue_id = wl.id
JOIN workers w ON sb.worker_id = w.id
JOIN completed_shifts cs ON w.id = cs.worker_id
JOIN documents d ON w.id = d.documentable_id
JOIN audits a ON d.id = a.auditable_id
JOIN industries i ON j.industry_id = i.id
WHERE sb.shift_id IN (253106)
AND d.document_type_id = 33
AND a.auditable_type = 'Document'
GROUP BY
sb.start_time::date,
wl.name,
w.first_name,
w.last_name,
i.title,
w.interviewed_on,
d.issue_date,
d.created_at,
a.user_id
a.user_id output will be something else I can set

Related

MOODLE - i need a query that returns latest enrolment date in course

this query is not returning correct latest_enrolment date. whenever i enrol a user in course, it doesnot updates enrolment date in database.. can anyone help?
SELECT TRIM(c.id) course_id,TRIM(c.fullname) course_fullname,FROM_UNIXTIME(u.timecreated) as registration ,FROM_UNIXTIME( ra.timemodified ) latest_enrolment_date,COUNT( * ) AS enrol_count
FROM mdl_user u
INNER JOIN mdl_role_assignments ra ON ra.userid = u.id
INNER JOIN mdl_context ct ON ct.id = ra.contextid
INNER JOIN mdl_course c ON c.id = ct.instanceid
INNER JOIN mdl_role r ON r.id = ra.roleid
INNER JOIN mdl_course_categories cc ON cc.id = c.category
WHERE r.id =5 GROUP BY c.id
Something like this
SELECT MAX(ue.timecreated) AS latest_enrolment_date
FROM mdl_enrol e
JOIN mdl_user_enrolments ue ON ue.enrolid = e.id
WHERE e.courseid = xx

Return records if all conditions Match

I need a query to return records if all conditions Match.
Example:
Lets say I have a User “John” (UserID: '37') that belongs to groups 'A','B','C' (GroupID: '47', '48', '166')
And I type
Select person, group
from persons p inner join groups g
on p.id = g.id
where p.id = '37'
and g.id in ('47','166')
The query should return No Record because not all conditions match, Group 'C' was not part of the query.
How can I do this?
This has to be a dup but I cannot find it
Select p.id
from persons p inner join groups g
on p.id = g.UserID
where p.id = '37'
and g.GroupID in ('47','166')
group by person
having count(*) = 2
--The subquery did what I was after
SELECT p.id, g.id
FROM persons p inner join groups g
on p.id = g.Userid
where g.Userid =
(select Userid from groups gs
where p.id = gs.Userid
And gs.id in (47,166)
group by g.Userid
having count(distinct gs.id) = 3)

How to aggregate calculation in SQL Server?

I have a following script to get the total unit but it gives me an error
Cannot perform an aggregate function on an expression containing an aggregate or a subquery.
Do I need to calculate SUM(ta.Qty) outside the main table?
SELECT
ta.ProductName
, SUM(ta.Total)
, SUM(SUM(ta.Qty) * ta.Unit)
FROM
tableA tA
INNER JOIN
tableB tB on tA.ID = tb.TableAID
INNER JOIN
tableC tc on ta.ID = tc.TableAID
INNER JOIN
tableD td on td.ID = tb.TableBID
GROUP BY
ta.ProductName
Here is a query in the AdventureWorks database that produces the same error (but might make some sense):
SELECT v.Name AS Vendor, SUM(SUM(p.ListPrice*d.OrderQty)+h.Freight)
FROM Production.Product p
INNER JOIN Purchasing.PurchaseOrderDetail d ON p.ProductID = d.ProductID
INNER JOIN Purchasing.PurchaseOrderHeader h ON h.PurchaseOrderID = d.PurchaseOrderID
INNER JOIN Purchasing.Vendor v ON v.BusinessEntityID = h.VendorID
GROUP BY v.Name
And here are two ways that I could rewrite that query to avoid the error:
SELECT v.Name AS Vendor, SUM(x.TotalAmount+h.Freight)
FROM (
SELECT PurchaseOrderID, SUM(p.ListPrice*d.OrderQty) AS TotalAmount
FROM Production.Product p
INNER JOIN Purchasing.PurchaseOrderDetail d ON p.ProductID = d.ProductID
GROUP BY PurchaseOrderID
) x
INNER JOIN Purchasing.PurchaseOrderHeader h ON h.PurchaseOrderID = x.PurchaseOrderID
INNER JOIN Purchasing.Vendor v ON v.BusinessEntityID = h.VendorID
GROUP BY v.Name
SELECT v.Name AS Vendor, SUM(x.TotalAmount+h.Freight)
FROM Purchasing.PurchaseOrderHeader h
INNER JOIN Purchasing.Vendor v ON v.BusinessEntityID = h.VendorID
CROSS APPLY (
SELECT SUM(p.ListPrice*d.OrderQty) AS TotalAmount
FROM Production.Product p
INNER JOIN Purchasing.PurchaseOrderDetail d ON p.ProductID = d.ProductID
WHERE d.PurchaseOrderID=h.PurchaseOrderID
) x
GROUP BY v.Name
The first query uses derived tables and the second one uses CROSS APPLY.

TSQL efficiency - INNER JOIN replaced by EXISTS

Can the following be rewritten to be more efficient?
I would use EXISTS if I didn't need fields from country but I do need those fields, and am not sure how to write this to make it more efficient.
SELECT distinct
p.ProvinceID,
p.Abbv as RegionCode,
p.name as RegionName,
cn.Code as CountryCode,
cn.Name as CountryName
FROM dbo.provinces AS p
INNER JOIN dbo.Countries AS cn ON p.CountryID = cn.CountryID
INNER JOIN dbo.Cities c on c.ProvinceID = p.ProvinceID
INNER JOIN dbo.Listings AS l ON l.CityID = c.CityID
WHERE l.IsActive = 1 AND l.IsApproved = 1
There are two things to note:
You're joining to dbo.Listings which results in many records, so you need to use DISTINCT (usually an expensive operator)
For any tables with columns not in the select you can move into an EXISTS (but the query planner effectively does this for you anyway)
So try this:
SELECT
p.ProvinceID,
p.Abbv as RegionCode,
p.name as RegionName,
cn.Code as CountryCode,
cn.Name as CountryName
FROM dbo.provinces AS p
INNER JOIN
dbo.Countries AS cn
ON p.CountryID = cn.CountryID
WHERE EXISTS (SELECT 1 FROM
dbo.Listings l
INNER JOIN dbo.Cities c
on l.CityID = c.CityID
WHERE c.ProvinceID = p.ProvinceID
AND l.IsActive = 1 AND l.IsApproved = 1
)
Check the query plans before and after - the query planner might be smart enough to do this anyway, but you have removed your distinct
The following will often perform even better by providing the optimizer more useful information:
SELECT
p.ProvinceID,
p.Abbv as RegionCode,
p.name as RegionName,
cn.Code as CountryCode,
cn.Name as CountryName
FROM dbo.provinces AS p
INNER JOIN
dbo.Countries AS cn
ON p.CountryID = cn.CountryID
INNER JOIN (
SELECT
p.ProvinceID
FROM
dbo.Listings l
INNER JOIN dbo.Cities c
on l.CityID = c.CityID
WHERE l.IsActive = 1 AND l.IsApproved = 1
GROUP BY
p.ProvinceID
) list
on list.ProvinceID = p.ProvinceID

Grades of each quiz in Moodle

I'm trying to get grades of each question, I have a query but it only return final grade of whole exam, but i want grade of each question, how to get it?
Here is query that i have:
SELECT mdl_grade_items.id AS ItemID,
mdl_course.shortname AS CourseShortname,
mdl_grade_items.itemname AS ItemName,
mdl_grade_items.grademax AS ItemGradeMax,
mdl_grade_items.aggregationcoef AS ItemAggregation,
mdl_grade_grades.finalgrade AS FinalGrade,
mdl_user.username AS StudentID,
mdl_user.id
FROM mdl_grade_items
INNER JOIN mdl_grade_grades
ON mdl_grade_items.id = mdl_grade_grades.itemid
INNER JOIN mdl_role_assignments
ON mdl_grade_grades.userid = mdl_role_assignments.userid
AND mdl_grade_items.courseid = mdl_role_assignments.mdlcourseid
INNER JOIN mdl_course
ON mdl_course.id = mdl_grade_items.courseid
INNER JOIN mdl_user
ON mdl_user.id = mdl_role_assignments.userid
Ok, i found it
SELECT mqa.id,meqi.grade * (select fraction from mdl_question_attempt_steps where
questionattemptid = mqas.questionattemptid and state like 'mangr%' order by id desc limit
1 ) finalgrade,me.course , mqas.userid,u.firstname, u.lastname, mqa.questionsummary,
mqa.responsesummary , meqi.grade
FROM mdl_question_attempts mqa
left JOIN mdl_question_attempt_steps mqas ON mqa.id = mqas.questionattemptid
left JOIN mdl_user u ON mqas.userid = u.id
left JOIN mdl_examm_question_instances meqi ON meqi.question = mqa.questionid
left JOIN mdl_examm me ON meqi.examm = me.id
WHERE me.course= $courseID and userid = $userID