How to change my Delete SQL query into LINQ - linq

I'm a little bit new in LINQ field.I have a Delete query like this:
DELETE FROM Table1 WHERE FK IN (SELECT ID FROM Table2 WHERE UserId = #UId)
How can I change it into a LINQ query?

This should give you an idea
var itemQuery = from cartItems in db.SalesOrderDetails
where cartItems.SalesOrderID == 75144
select cartItems.ProductID;
var myProducts = from p in db.Products
where itemQuery.Contains(p.ProductID)
select p;
foreach (var detail in myProducts )
{
db.myProducts.DeleteOnSubmit(detail);
}
try
{
db.SubmitChanges();
}
catch (Exception e)
{
Console.WriteLine(e);
// Provide for exceptions.
}

Related

Querydsl - filter on Left join with subquery

I have one of the complex query dynamically generated through Querydsl predicate and JPQL. I am also using the Q classes.
I am able to generate the following query by passing a predicate to the JPA repository.
select company0_.id as id1_18_,
company0_.name as name2_18_
from company company0_
left outer join companyAddress companyadd1_ on company0_.id=companyadd1_.company_id
where company0_.id in
(select companyadd2_.company_id
from companyAddress companyadd2_
where companyadd2_.address_type='1')
order by companyadd1_.addressline1;
but I want the query mentioned below
select company0_.id as id1_18_,
company0_.name as name2_18_
from company company0_
left outer join companyAddress companyadd1_ on company0_.id=companyadd1_.company_id
and companyadd1_.status = 'Active' -- New added(Failed to implement this)
where company0_.id in
(select companyadd2_.company_id
from companyAddress companyadd2_
where companyadd2_.address_type='1'
and and companyadd2_.status = 'Active') -- New Added(I am able to achieve this)
order by companyadd1_.addressline1;
We are using following kind of code, I can not possibly to share exact code due to security concern but you can help me by providing basic structure or code to achieve this.
final JPQLQuery<QCompanyAlias> subQuery = new JPAQuery<>();
BooleanExpression exp = null;
QueryBase<?> q = (QueryBase<?>) subQuery.from(qCompanyAddress);
if (requestMap.containsKey(CompanyQueryConstants.ADDRESS_TYPE)) {
BooleanExpression addrExp = null;
for (String addressType : addressTypes) {
if (addrExp == null) {
addrExp = qCompanyAddress.addressType.addressTypeCode.eq(addressType);
} else {
addrExp = addrExp.or(qCompanyAddress.addressType.addressTypeCode.eq(addressType));
}
}
exp = addrExp;
}
To add join on two conditions use
new JPAQuery(em)
.from(qCompany)
.leftJoin(qCompany, qCompanyAddress.company)
.on(
qCompany.id.eq(qCompanyAddress.company.id)
.and(qCompanyAddress.status.eq(status))
);
For subquery try to use this
final JPQLQuery<QCompanyAlias> subQuery = new JPAQuery<>();
BooleanExpression exp = null;
QueryBase<?> q = (QueryBase<?>) subQuery.from(qCompanyAddress);
if (requestMap.containsKey(CompanyQueryConstants.ADDRESS_TYPE)) {
BooleanExpression addrExp = null;
for (String addressType : addressTypes) {
if (addrExp == null) {
addrExp = qCompanyAddress.addressType.addressTypeCode.eq(addressType);
} else {
addrExp = addrExp.or(qCompanyAddress.addressType.addressTypeCode.eq(addressType));
}
}
exp = addrExp;
}
BooleanExpression statusExp = qCompanyAddress.status.eq(status);
if(exp == null) {
exp = statusExp;
} else {
exp = statusExp.and(exp);
}
But in your case I can't understand the reason for filtering by status twice. Subquery filtering should be enought. I suspect that you can achieve the same result without subquery. It depends on your entities.

How to Sortby Multiple Colums - Linq to SQL

Wanting to sortby x.IRNumber - .thenby x.BedLocation but no luck could someone help me in the right direction?
Thanks
Mark
string jobID = ddlJobID.SelectedValue;
using (rw_forms context = new rw_forms())
{
var result = from c in context.hospedia_running_sheet_view.Select(x => new
{
x.uniqueID,
x.irNumber,
x.ward,
x.bed_location,
x.bed_extension,
x.select_technology,
x.select_fitting_of_pattress,
x.select_fitting_of_backplate,
x.fixing_method_used,
x.id,
x.status,
x.latitude,
x.longitude,
x.accuracy,
x.createdAt,
x.createdByName,
x.fixing,
x.statusID,
x.commissioningID,
x.jobID,
x.siteName
}).Where(x=> x.statusID == 1).Where(x => x.jobID == ((jobID == "-1") ? x.jobID : jobID)).OrderByDescending(x => x.irNumber) select c;
grdForms.DataSource = result.ToList();
grdForms.DataBind();
}
}
catch(Exception ex)
{
Response.Write(ex.ToString());
}
}
If you want something like this
SELECT * FROM TEST
ORDER BY TEST.ID,TEST.RID DESC
-
from t in db.TEST
orderby t.ID, t.RID descending
select t

LINQ Update query with Join condition

trying to do LINQ Update query using join with on condition also And condition
Following my SQL Query
UPDATE tbl_gs_related_orders
SET RelatedCOI = sop.ServiceOrderNo
FROM tbl_service_order_progress sop
JOIN tbl_gs_related_orders ro ON sop.parentid = ro.RelatedOrderParentId
AND ro.RelatedCOIIdentifier collate database_default = sop.InstanceIdentifier collate database_default
WHERE ro.ParentId = #PARENTID
AND ro.relatedorderparentid IS NOT NULL
This Query i want to convert into LINQ SO following my update LINQ query but getting some error like "the type of one of the expressions in the join clause is incorrect type inference failed in the call to join"
var updateQuery = (from c in ctxParser.TBL_SERVICE_ORDER_PROGRESS
join o in ctxParser.tbl_GS_Related_Orders on new { ParentId = c.ParentId, InstanceIdentifier = c.InstanceIdentifier }
equals new { RelatedOrderParentId = o.RelatedOrderParentId, RelatedCOIIdentifier = o.RelatedCOIIdentifier }
where ro.RelatedOrderParentId == sParentId && ro.RelatedOrderParentId != null
select new
{
ServiceOrderNo = c.ServiceOrderNo,
Order = o
});
foreach (var item in updateQuery)
{
item.Order.RelatedCOI = item.ServiceOrderNo;
}
ctxParser.SaveChanges();
Use same aliases when creating Anonymous type for equals clause:
from c in ctxParser.TBL_SERVICE_ORDER_PROGRESS
join o in ctxParser.tbl_GS_Related_Orders on new { ParentId = c.ParentId, InstanceIdentifier = c.InstanceIdentifier }
equals new { ParentId = o.RelatedOrderParentId, InstanceIdentifier = o.RelatedCOIIdentifier }

Compare a linq value (int) to an int List using where clause

I have a linq query which joins a couple of tables and returns the value into an object. The query was working fine, till i added a where clause to in. Aftre the where clause, my query returns null.
Here's the code:
List<Int32> resourceSupervisorIdList = new List<Int32>();
resourceSupervisorIdList.Add(searchCriteriaTimesheet.ResourceId);
foreach (resource res in allSubordinateResources)
{
if (!resourceSupervisorIdList.Contains(res.id_resource))
resourceSupervisorIdList.Add(res.id_resource);
}
using (tapEntities te = new tapEntities())
{
var timesheetAll = (from tsh in te.timesheet_header
join rs in te.resources on tsh.id_resource equals rs.id_resource
join tsd in te.timesheet_detail on tsh.id_timesheet equals tsd.id_timesheet
where (resourceSupervisorIdList.Contains(rs.id_resource_supervisor))
select new TimesheetHeaderDetailsItem()
{
OrganizationId = rs.id_organization,
ProjectId = tsd.id_project,
StartDate = tsh.dte_period_start,
EndDate = tsh.dte_period_end,
ApprovedDate = tsh.dte_approved,
RejectedDate = tsh.dte_rejected,
SubmittedDate = tsh.dte_submitted,
});
if (timesheetAll == null || timesheetAll.Count() == 0)
{
return result;
}
}
Now, after adding the where clause, the code runs into the if condition. There are matching records in the table, but still i'm not able to get any records.
rs.id_resource_supervisor
is of type int in the mysql db.

How to: linq query

I am trying to get a record from database using linq but it keep return no record
it is very basic sql statment
select * where productid ='12553'
however the following code does not return any result. Please advise. thx you
private static IEnumerable<ProductModel> GetAllProduct(string productId)
{
using (var dc = new TestEntities())
{
var result = (from a in dc.Products
where a.productid == productId
select new ProductModel
{
ProductId = a.productid,
Name = a.ProductName
});
return result.Distinct().ToList();
}
}
You don't need projection here:
using (var dc = new TestEntities())
{
var result = from a in dc.Products
where a.productid == productId
select a;
return result.Distinct().ToList();
}

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