Table 1:
productId
productName
Table 2:
Id
productId - foregn key with references to table 1
productLoacation
I want toselect productId,productName and list of productLoactions?
I have tried as below,
var mailAddress = from tb1 in DbContext.table1
join tb2 in DbContext.Table2 on tb1.productId equals tb2.productId
where tb1.table1== 1234
select { tb1.productName, tb2.productLoacation.ToList()};
How can I achive in a single query without creating a entity?
You can try this query (I suppose, that table1
field is unique identifier):
var mailAddress = (from tb1 in DbContext.table1
where tb1.table1 == 1234
join tb2 in DbContext.Table2 on tb1.productId equals tb2.productId
group tb2 by new { tb1.productId, tb1.productName } into sub
select new {
sub.Key.productId,
sub.Key.productName,
productLocations = sub.ToList()
}).FirstOrDefault();
Another way is to use Future
from EntityFramework.Extended library:
var fromTable1Query = DbContext.table1.Where(x => x.table1 == 1234).Future();
var fromTable2Query = (from tb1 in DbContext.table1
where tb1.table1 == 1234
join tb2 in DbContext.table2 on tb1.productId equals tb2.productId
select tb2).Future();
mailAddress.product = fromTable1Query.ToList().FirstOrDefault();
mailAddress.productLocations = fromTable2Query.ToList();
These two queries will be executed together in exactly one trip to database.
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