Its just a simple Linq to Entity update query i tried with the following code but it doesn't update the "User" column in the DB.
Its not even throwing any exception also,please some one point me what am missing here.
MyEntities db = new MyEntities ();
var query = from SEVTs in db.SEVTs
where SESID == "4747747"
select SEVTs;
foreach (var SEVTs in query) {
SEVTs.USER = "Test";
}
db.SaveChanges();
Quite interesting, when i try the follwing query in the sql server its not update the record
update Schedwin.SEVT
set
USER3='Test'
Where
SESID='4747747' // here i pass the value as a string
SESID data type is CHAR and its a primary key. if i pass the value as SESID=4747747 then it update that record.
Please ignore my question.
Here what i missed my input value SESID == "4747747" //this have whitespace that's why it didn't updated that particular record.
Thanks All
You are nor modifying SEVTs.USER, but some local variable.
(BTW: create a context in a using construct)
Related
Please check the below query I am trying to update a row by the composite key
my key combination is like:
int id
int versionId
String languageId
and query is:
#Transactional
#Modifying
#Query("update languageEntity l set l.language = :language where l.languageId = :languageId")
int UpdateProcessLanguage(#Param("language ") String processDesTranslation, #Param("languageId ") UserLanguageId languageId);
I am not getting any exception. function is returning 0, means no row effected.
please check what is worng.
It's hard to say without knowing the data. As a first step I would log the generated SQL statements (see how to log sql statements in spring-boot) and check if they look right.
Why you dont wan't to use save() method for that? Just change language property on your object and pass it to the save method. It will update the row.
Within a project I have a database table with the following columns
I would like to be able to delete from this table all rows which have a matching SharingAgencyId and ReceivingAgencyId values that I can pass in.
What I have tried so far:
public static ICollection<SecurityDataShare> UpdateSharedEntites(long conAgency, long recAgency)
{
ICollection<SecurityDataShare> agShares = null;
try
{
using (var context = new ProjSecurityEntities(string.Empty))
{
agShares = (from a in context.SecurityDataShares
.Where(c => c.ReceivingAgencyId == recAgency && c.SharingAgencyId == conAgency)
select a);
}
}
catch (Exception ex)
{
//ToDo
throw;
}
}
My thought process was to retrieve the records where the id's matched the parameters passed in and then using a foreach loop iterate through (agShare) and remove each row followed by saving my changes. With the current implementation I don't seem to have access to any of the Delete methods.
Looking to the example above I'd appreciate any suggestions on how to remove the rows within the table that contained a value of 43 and 39 using dbContext.
Cheers
If I understand right, your DbContext's properties, like SecurityDataShares should be typed as IDbSet<SecurityDataShare>. If that's correct, you should be able to use this Remove method.
foreach(var agShare in agShares) {
context.SecurityDataShares.Remove(agShare);
}
context.SaveChanges();
Be aware that this creates a separate SQL statement for deleting these objects. If you expect the number of objects to be rather large, you may want to use a stored procedure instead.
Entity Framework doesn't make it easy to run a single command to delete multiple rows (that I know of). My preference is to run a SQL statement directly for multi-entity updates/deletes using native sql with the dbcontext of sorts.
you can also pass datatable to the stored procedure with database contain dynamic type table of your type and
use that table into stored procedure for deleting matching rows from Database table.
db.AdDetails.Where( u => u.OwnerGUID == CurrentUserProviderKey)
I have an adDetails table that has an OwnerGUID field.
I want to pull out only ad details that belong to the currenly logged in user.
My query does not show any where clauses in the SQL when I look at it in the debugger.
Can someone help me figure out what is wrong with my statement and if all rows in the table will be brought back then all 10K records put though a where on the webserver?
I am really new to this.
Using the Where extension method will filter down the results.
Queries in Entity Framweork are not executed until you iterate over them. If you do:
var query = db.Where(u => u.OwnerGUID == key);
This does not execute the query. When you do the following:
var list = list.ToList();
OR
foreach( var item in query) { ... }
That is when the query will be executed in SQL. The results should be filtered with your WHERE clause at this point.
I have created a linq query that returns my required data, I now have a new requirement and need to add an extra field into the returned results. My entity contains an ID field that I am trying to map against another table without to much luck.
This is what I have so far.
Dictionary<int, string> itemDescriptions = new Dictionary<int, string>();
foreach (var item in ItemDetails)
{
itemDescriptions.Add(item.ItemID, item.ItemDescription);
}
DB.TestDatabase db = new DB.TestDatabase(Common.GetOSConnectionString());
List<Transaction> transactionDetails = (from t db.Transactions
where t.CardID == CardID.ToString()
select new Transaction
{
ItemTypeID= t.ItemTypeID,
TransactionAmount = t.TransactionAmount,
ItemDescription = itemDescriptions.Select(r=>r.Key==itemTypeID).ToString()
}).ToList();
What I am trying to do is key the value from the dictonary where the key = itemTypeID
I am getting this error.
Local sequence cannot be used in LINQ to SQL implementations of query operators except the Contains operator.
What do I need to modify?
This is a duplicate of this question. The problem you're having is because you're trying to match an in-memory collection (itemDescriptions) with a DB table. Because of the way LINQ2SQL works it's trying to do this in the DB which is not possible.
There are essentially three options (unless I'm missing something)
1) refactor your query so you pass a simple primitive object to the query that can be passed accross to the DB (only good if itemDescriptions is a small set)
2) In your query use:
from t db.Transactions.ToList()
...
3) Get back the objects you need as you're doing, then populate ItemDescription in a second step.
Bear in mind that the second option will force LINQ to evaluate the query and return all transactions to your code that will then be operated on in memory. If the transaction table is large this will not be quick!
Is there any reason something like this would not work?
This is the logic I have used many times to update a record in a table with LINQ:
DataClasses1DataContext db = new DataClasses1DataContext();
User updateUser = db.Users.Single(e => e.user == user);
updateUser.InUse = !updateUser.InUse;
db.Log = new System.IO.StreamWriter(#"c:\temp\linq.log") { AutoFlush = true };
db.SubmitChanges();
(updateUser.InUse is a bit field)
For some reason it isn't working. When I check the linq.log it is completely blank.
Could there be a problem with my .dbml? Other tables seem to work fine but I've compared properties in the .dbml and they all match.
It's as if the db.SubmitChanges(); does not detect any updates being required.
The table could not be updated properly because it had no primary key. (Actually it had the column but the constraint was not copied when I did a SELECT INTO my dev table). The DataContext class requires a primary key for updates.
Is the InUse property a "normal" one as far as LINQ is concerned? (e.g. it's not autogenerated or anything funky like that?)
Alternatively, I don't suppose it's a Nullable<bool> is it, with a current value of null? If so, your update line isn't actually doing anything - for nullable Booleans, !null = null.