I have this existing Sql statement:
Select Count(ordid),isnull(prcsts,'NOT STARTED')
from lwp
where lwp in( Select max(Id) from lwp group by ordid)
group by prcsts
I want to convert to use linq-to-sql, but I'm can't figure out how to handle the group by expression in the sub query. How can I do this?
I am using Entity Framework where I have a method to get the list of lwp. I did only part of it.
Entitydb.lwpmethod
.GetList
.Where(Function(F) F.ID = **Max(Function(O) O.ordid**)
.GroupBy(Function(F) F.prcsts)
.Select(Function(F) New With {.A = F.Count, .B = F.Key})
.ToList
I am unable to write the group by subquery in the max function.
First off, that's not an in, that's an = since max() returns a single element. Also your sql query has lwp in the where clause, you probably typo'd id. With that in mind, what you want is something like:
.Where(row=>row.ID=Entitydb.lwpmethod.GetList()
.Where(r=>r.ordid=row.ordid)
.Max(r=>r.ID))
C# code, but you get the idea.
By the way this looks like it's selecting the last row. Why not just sort by id descendently and take the first element?
Related
How to Convert this sql query to Linq.
select sum(OutstandingAmt)from IvfReceiptDetails where IvfReceiptId IN(select IvfReceiptId from IvfReceipts where PatientId = 'SI-49650')
I think it is easier to translate SQL using query comprehension syntax instead of lambda syntax.
General rules:
Translate inner queries into separate query variables
Translate SQL phrases in LINQ phrase order
Use table aliases as range variables, or if none, create range variables from table names
Translate IN to Contains
Translate SQL functions such as DISTINCT or SUM into function calls on the entire query.
Here is the code:
var IvfReceiptIds = from IvfReceipt in IvfReceipts
where IvfReceipt.PatientId = "SI-49650"
select IvfReceipt.IvfReceiptId;
var OutstandingAmtSum = (from IvfReceiptDetail in IvfReceiptDetails
where IvfReciptIds.Contains(IvfReceiptDetail.IvfReceiptId)
select IvfReceiptDetail.OutstandingAmt).Sum();
Try this, First get all IvfReceiptId in array based on your inner query used in where condition then check contains. Change name of your _context if it's different.
var arrIvfReceiptId = _context.IvfReceiptDetails.Where(p=>p.PatientId == "SI-49650").ToArray();
var sum = (from ird in _context.IvfReceiptDetails.Where(p=> arrIvfReceiptId.Contains(p.IvfReceiptId))
select OutstandingAmt).Sum();
How can you use a LET temporary variable inside the Where clause in an OrientDB SQL subQuery.
Here is the context in wich I'm trying to use it.
select *, $t.d from Currency
let $t = (select createdDate.asLong() as d from 13:1)
where createdDate.asLong() >= $t.d and #rid <> #13:1
order by createdDate ASC
The validation in the where statement for the dates does not work. The subQuery actually works on its own. The Query works as well when replacing $t.d with the result from the subQuery.
The $t.d is an array so you are comparing something like createdDate.asLong() >= [1234599]
You have to do this: createdDate.asLong() >= $t[0].d
First of all, I know there are already questions and answers about it, this thread being the one that is closest to what I need:
SQL Update to the SUM of its joined values
However, I get a syntax error (operator missing) that seems to occur close to the FROM clause. However I can't see it. Does it not like the FROM itself ? I am not used to using FROM in an update statement but it seems like it's valid from the QA I just linked :|
Any idea why there would be a syntax error there ?
I am using Access 2007 SP3.
Edit:
Wow, I forgot to post the query...
UPDATE r
SET
r.tempsmoy_requete_min = tmm.moy_mob_requete
FROM
rapports AS r INNER JOIN
(SELECT
id_fichier,
Round(Sum(temps_requete_min)/3,0) As moy_mob_requete,
Round(Sum(temps_analyse_min)/3,0) As moy_mob_analyse,
Round(Sum(temps_maj_min)/3,0) As moy_mob_maj,
Round(Sum(temps_rap_min)/3,0) As moy_mob_rap,
Round(Sum(temps_ddc_min)/3,0) As moy_mob_ddc
FROM maintenances
WHERE
periode In (10,9,8) And
annee=2011
GROUP BY id_fichier) AS tmm ON rapports.id_rapport = tmm.id_fichier
WHERE
1=0
The WHERE 1=0 part is because I want to test further the subquery before running it.
Edit: This is some simpler query I am trying. I get a different error this time. It now tells me that tempsmoy_requete_min (and probably all other left operands) are not part of an aggregate function... which is the point of my query. Any idea ?
UPDATE
rapports INNER JOIN maintenances ON rapports.id_rapport = maintenances.id_fichier
SET
rapports.tempsmoy_requete_min = Round(Sum(temps_requete_min)/3,0),
rapports.tempsmoy_analyse_min = Round(Sum(temps_analyse_min)/3,0),
rapports.tempsmoy_maj_min = Round(Sum(temps_maj_min)/3,0),
rapports.tempsmoy_rap_min = Round(Sum(temps_rap_min)/3,0),
rapports.tempsmoy_ddc_min = Round(Sum(temps_ddc_min)/3,0)
WHERE
maintenances.periode In (10,9,8) And
maintenances.annee=2011 AND
1=0
I tried adapting your first query sample, and was able to make your error go away. However then I encountered a different error ('Operation must use an updateable query').
It may be possible to overcome that error, too. However, I found it easier to use a domain function instead of a join to retrieve the replacement value.
UPDATE rapports
SET tempsmoy_requete_min = Round(DSum("temps_requete_min",
"maintenances",
"periode In (10,9,8) AND annee=2011 "
& "AND id_fichier='" & id_rapport
& "'")/3, 0);
If this suggestion works for tempsmoy_requete_min with your data, you will have to extend it to the other fields you want to replace. That won't be pretty. You could make it less ugly with a saved query which you then use as the "Domain" parameter for DSum() ... that could allow you to use a simpler "Criteria" parameter.
UPDATE r
should be
UPDATE rapports
You can't reliably use an alias in the update target.
suppose we have a model in django defined as follows:
class Literal:
name = models.CharField(...)
...
Name field is not unique, and thus can have duplicate values. I need to accomplish the following task:
Select all rows from the model that have at least one duplicate value of the name field.
I know how to do it using plain SQL (may be not the best solution):
select * from literal where name IN (
select name from literal group by name having count((name)) > 1
);
So, is it possible to select this using django ORM? Or better SQL solution?
Try:
from django.db.models import Count
Literal.objects.values('name')
.annotate(Count('id'))
.order_by()
.filter(id__count__gt=1)
This is as close as you can get with Django. The problem is that this will return a ValuesQuerySet with only name and count. However, you can then use this to construct a regular QuerySet by feeding it back into another query:
dupes = Literal.objects.values('name')
.annotate(Count('id'))
.order_by()
.filter(id__count__gt=1)
Literal.objects.filter(name__in=[item['name'] for item in dupes])
This was rejected as an edit. So here it is as a better answer
dups = (
Literal.objects.values('name')
.annotate(count=Count('id'))
.values('name')
.order_by()
.filter(count__gt=1)
)
This will return a ValuesQuerySet with all of the duplicate names. However, you can then use this to construct a regular QuerySet by feeding it back into another query. The django ORM is smart enough to combine these into a single query:
Literal.objects.filter(name__in=dups)
The extra call to .values('name') after the annotate call looks a little strange. Without this, the subquery fails. The extra values tricks the ORM into only selecting the name column for the subquery.
try using aggregation
Literal.objects.values('name').annotate(name_count=Count('name')).exclude(name_count=1)
In case you use PostgreSQL, you can do something like this:
from django.contrib.postgres.aggregates import ArrayAgg
from django.db.models import Func, Value
duplicate_ids = (Literal.objects.values('name')
.annotate(ids=ArrayAgg('id'))
.annotate(c=Func('ids', Value(1), function='array_length'))
.filter(c__gt=1)
.annotate(ids=Func('ids', function='unnest'))
.values_list('ids', flat=True))
It results in this rather simple SQL query:
SELECT unnest(ARRAY_AGG("app_literal"."id")) AS "ids"
FROM "app_literal"
GROUP BY "app_literal"."name"
HAVING array_length(ARRAY_AGG("app_literal"."id"), 1) > 1
Ok, so for some reason none of the above worked for, it always returned <MultilingualQuerySet []>. I use the following, much easier to understand but not so elegant solution:
dupes = []
uniques = []
dupes_query = MyModel.objects.values_list('field', flat=True)
for dupe in set(dupes_query):
if not dupe in uniques:
uniques.append(dupe)
else:
dupes.append(dupe)
print(set(dupes))
If you want to result only names list but not objects, you can use the following query
repeated_names = Literal.objects.values('name').annotate(Count('id')).order_by().filter(id__count__gt=1).values_list('name', flat='true')
SQL query in Ms-Access
INSERT INTO tblTmpEventLog( TrackingNumber, PartNumber, PartNumberChgLvl,
EnteredBy, EventTypeSelected, EventDate )
SELECT DISTINCT tblRevRelLog_Detail.RevRelTrackingNumber,
tblRevRelLog_Detail.PartNumber, tblRevRelLog_Detail.ChangeLevel,
[Forms]![frmEventLog_Input]![EnteredBy] AS EnteredBy,
[Forms]![frmEventLog_Input]![EventTypeSelected] AS EventTypeSelected,
CDate([Forms]![frmEventLog_Input]![EventDate]) AS EventDate
FROM tblRevRelLog_Detail LEFT JOIN tblEventLog
ON (tblEventLog.PartNumber = tblRevRelLog_Detail.PartNumber)
AND (tblEventLog.PartNumberChgLvl = tblRevRelLog_Detail.ChangeLevel)
WHERE ((([tblRevRelLog_Detail]![RevRelTrackingNumber]) =
[Forms]![frmEventLog_Input]![TrackingNumber]))
AND ((tblEventLog.PartNumber) NOT IN
(SELECT tblEventLog.PartNumber FROM tblEventLog
WHERE tblEventLog.EventTypeSelected = 'pn REMOVED From Wrapper'
AND tblEventLog.TrackingNumber =
tblRevRelLog_Detail.RevRelTrackingNumber
AND tblEventLog.PartNumber = tblRevRelLog_Detail.PartNumber
AND tblEventLog.PartNumberChgLvl =
tblRevRelLog_Detail.ChangeLevel
));
DISTINCT keyword for EnteredBy, EventTypeSelected is not working..I mean, data for these columns is not displaying when I use DISTINCT keyword.
EVENTDATE is working fine, but I do not understand why is it not displaying for EneteredBy and EventTypeSelected columns.
Can anyone tell me how to handle this?
It may be that the query can't interpret properly from the form directly as the final data type. However in your date field, you are wrapping it in a function CDATE( ... ). So, the SQL engine knows the result type. I would suggest doing the same for the other fields. Ex: doing a CAST ( ...your form control... as DateTime ) as OtherColumn, etc... I THINK Access allows casting, but not positive. Otherwise, pre-pull the form value into a declared data type variable and use THAT variable in the query AS OtherColumn as you are doing.
Additionally to what #Jack mentioned, you can always go back to your account, look at your historical question, and click on whatever answers actually helped / solve your problems. Some questions never do get answers and that's ok, just give credit to those that DO help.
I have found in the past (I don't remember which old version of Access this was) that if you set the value of a form control in VBA, and then use that control in a query, the query will not see the value you set in VBA. If the user edits the control normally, the query sees the expected value. Perhaps that's what happened here.
To work around that, you can declare a VBA function that returns the desired value. For example, instead of this:
SELECT ..., Forms!MainForm!TextEntry AS TextEntry, ... FROM ...
use this:
SELECT ..., GetTextEntry() AS TextEntry, ... FROM ...
along with this:
Public Function TextEntry() As Variant
TextEntry = Forms!MainForm!TextEntry
End Function