I have an entity query that when I run increments the value of my field. I am using entity framework and sql server 2012. Here is my query;
public void GetLastAccountNumber(ProductLine productLine, Action completed)
{
EntityQuery query = WASMDomainContext.GetContactCustomerAccountsQuery()
.Where(cca => cca.ProductLineId == productLine.Id)
.OrderBy(cca => cca.AccountNumber);
WASMDomainContext.Load(query, loadOp =>
{
Exception error = null;
ContactCustomerAccount lastAccount = null;
if (loadOp.HasError)
error = loadOp.Error;
else
lastAccount = loadOp.Entities.LastOrDefault();
// Invoke completion callback
completed(lastAccount, error);
}, null);
}
Query should return the last account number which is an integer field for now. However it returns an incremented value. For example in my table I have an accountnumber 0 the query returns an entity with account number as 1. My account number field is not auto increament and I find this very strange. And each time the above is called the AccountNumber field value increases by one but the database value will remain 0. I just want the query to return what is in my database. Any idea why this could be happening? Any help will be appreciated. Thank you all.
Related
I'm new to salesforce and I'm trying to learn more. Currently I'm stuck at a point where I don't know what to do further. Kindly point me in the right direction. Any help is appreciated.
So what im trying to do is to compare lastnames to find duplicates when the record is being created and if a duplicate is found then instead of creating it as a new record it should be merged with existing record.
So to achieve the task I have wrote the following trigger handler:
public class LeadTriggerHandler {
public static void duplicateMerge(){
List<Lead> leadList = [SELECT Id,Name, Email, Phone, FirstName, LastName FROM Lead];
List<Lead> leadTrigger = Trigger.new;
for(Lead leadVarTrigger : leadTrigger){
for(Lead leadVar : leadList){
//System.debug(leadVar.LastName + '==' + leadVarTrigger.LastName);
if(leadVarTrigger.LastName == leadVar.LastName)
{
//System.debug(leadVar.LastName + '==' + leadVarTrigger.LastName);
//leadVarTrigger.addError('This is a duplicate record');
Database.merge(leadVar, leadVarTrigger);
System.debug('Trigger Successful');
}
}
}
}
}
the following is my trigger:
trigger LeadTrigger on Lead (after insert) {
if(Trigger.isafter && Trigger.isInsert)
{
LeadTriggerHandler.duplicateMerge();
}
}
And when I try with after insert i get the following error:
LeadTrigger: execution of AfterInsert caused by: System.DmlException: Merge failed. First exception on row 0 with id 00Q5j00000ENUGVEA5; first error: INVALID_FIELD_FOR_INSERT_UPDATE, Unable to create/update fields: Name. Please check the security settings of this field and verify that it is read/write for your profile or permission set.: [Name] Class.LeadTriggerHandler.duplicateMerge: line 18, column 1 Trigger.LeadTrigger: line 5, column 1
And if i try with before trigger i get the following error for the same code:
LeadTrigger: execution of BeforeInsert caused by: System.StringException: Invalid id at index 0: null External entry point Trigger.LeadTrigger: line 5, column 1
Actually, according to your code, you are allowing the record to be created and saved to the database by using after insert. Your before insert failed because your handler class is referencing an Id, however, if you use before logic, the record isn't saved to the database yet, meaning it doesn't have an Id. With that being said, let's try the following. :)
The Trigger (Best practice is to have one trigger with all events):
trigger TestTrigger on Lead (before insert, before update, before delete, after insert, after update, after delete, after undelete) {
if(Trigger.isafter && Trigger.isInsert)
{
//Can't conduct DML operations with trigger.new or trigger.old
//So we will create a set and send this to our handler class
Set<Id> leadIds = Trigger.newMap.keySet();
LeadTriggerHandler.duplicateMerge(leadIds);
}
}
The Handler Class:
public class LeadTriggerHandler {
public static void duplicateMerge(Set<Id> idsFromTrigger){
//Querying the database for the records created during the trigger
List<Lead> leadTrigger = [SELECT Id, LastName FROM Lead WHERE Id IN: idsFromTrigger];
List<String> lastNames = new List<String>();
//This set is important as it prevents duplicates in our dml call later on
Set<Lead> deDupedLeads = new Set<Lead>();
List<Lead> leadsToDelete = new List<Lead>();
for (Lead l : leadTrigger){
//getting all of the Last Names of the records from the trigger
lastNames.add(l.lastName);
}
//We are querying the database for records that have the same last name as
//the records that were created during our trigger
List<Lead> leadList = [SELECT Id, Name, Email, Phone, FirstName, LastName FROM Lead WHERE LastName IN: lastNames];
for(Lead leadInTrigger : leadTrigger){
for(Lead leadInList : leadList){
if(leadInTrigger.LastName == leadInList.LastName){
//if the lead from the trigger has the same last name as a lead that
//already exists, add it to our set
deDupedLeads.add(leadInTrigger);
}
}
}
//add all duplicate leads from our set to our list and delete them
leadsToDelete.addAll(deDupedLeads);
delete leadsToDelete;
}
}
This handler has been bulkified in two ways, we removed the DML operation out of the loop and the code is able to process a scenario where someone mass inserts 1000s of leads at a time. Plus, rather than querying every lead record in your database, we only query for records that have the same last name as the records created during the insert operation. We advise using something more unique than LastName like Email or Phone as many people/leads can have the same Last Name. Hope this helps and have a blessed one.
I have a stored procedure that return a record count in SQL based on certain criteria. I am trying to retrieve this count in EF Core 3 so I can pass it into an angular app. When I test the SP in SQL it returns the expected result. In the controller I configured an action route to call the SP
[Route ("[action]")]
public async Task<IActionResult> GetCountOverdueLowPriorityWorkOrders()
{
var GetCountOverdueLowPriorityWorkOrders = await _repo.GetCountOverdueLowPriorityWorkOrders();
return Ok(GetCountOverdueLowPriorityWorkOrders);
}
When I test this call from Postman, I get the following error:
System.InvalidOperationException: The required column 'ID' was not present in the results of a 'FromSql' operation.
I am fairly new to programming, so any help would be greatly appreciated.
Thanks!
The column containing the values for COUNT(id) needs to be aliased as id.
Try this
SELECT COUNT(id) as ID FROM Workorders WHERE Severity = 1 AND Due < CAST(Current_TimeStamp AS DATE)
In my current project i am working with the database which has very strange table structure (All Id Fields in most tables are marked as not nullable and primary while there is not auto increment increment enabled for them those Id fields need to be unique as well).
unfortunately there is not way i can modify DB so i find another why to handle my problem.
I have no issues while querying for data but during insert What i want to do is,
To get max Id from table where entity is about to be inserted and increment it by one or even better use SSELECT max(id) pattern during insert.
I was hoping to use Interceptor inside EF to achieve this but is looks too difficult for me now and all i managed to do is to identify if this is insert command or not.
Can someone help me through my way on this problem? how can i achieve this and set ID s during insert either by selecting max ID or using SELECT max(id)
public void TreeCreated(DbCommandTreeInterceptionContext context)
{
if (context.OriginalResult.CommandTreeKind != DbCommandTreeKind.Insert && context.OriginalResult.DataSpace != DataSpace.CSSpace) return;
{
var insertCommand = context.Result as DbInsertCommandTree;
var property = insertCommand?.Target.VariableType.EdmType.MetadataProperties.FirstOrDefault(x => x.Name == "TableName");
if (property == null) return;
var tbaleName = property?.Value as ReadOnlyCollection<EdmMember>;
var variableReference = insertCommand.Target.VariableType.Variable(insertCommand.Target.VariableName);
var tenantProperty = variableReference.Property("ID");
var tenantSetClause = DbExpressionBuilder.SetClause(tenantProperty, DbExpression.FromString("(SELECT MAX(ID) FROM SOMEHOWGETTABLENAME)"));
var filteredSetClauses = insertCommand.SetClauses.Cast<DbSetClause>().Where(sc => ((DbPropertyExpression)sc.Property).Property.Name != "ID");
var finalSetClauses = new ReadOnlyCollection<DbModificationClause>(new List<DbModificationClause>(filteredSetClauses) { tenantSetClause });
var newInsertCommand = new DbInsertCommandTree(
insertCommand.MetadataWorkspace,
insertCommand.DataSpace,
insertCommand.Target,
finalSetClauses,
insertCommand.Returning);
context.Result = newInsertCommand;
}
}
Unfortunately that concept of Interceptor is a little bit new for me and i do not understand it completely.
UPDATE
I manage to dynamically build that expression so that ID field is now included in insert statement, but the problem here is that I can not use SQL query inside it. whenever i try to use this it always results in some wrong SQL query so is there anyway i tweak insert statement so that this SELECT MAX(ID) FROM TABLE_NAME is executed during insert?
Get the next id from the context, and then set the parameter of the insert command accordingly.
void NonQueryExecuting(DbCommand command, DbCommandInterceptionContext<int> interceptionContext)
{
var context = interceptionContext.DbContexts.First() as WhateverYourEntityContainerNameIs;
// get the next id from the database using the context
var theNextId = (from foo in context...)
// update the parameter on the command
command.Parameters["YourIdField"].Value = theNextId;
}
Just bear in mind this is not terribly thread safe; if two users update the same table at exactly the same time, they could theoretically get the same id. This is going to be a problem no matter what update method you use if you manage keys in the application instead of the database. But it looks like that decision is out of your hands.
If this is going to be a problem, you might have to do something more drastic like alter the command.CommandText to replace the value in the values clause with a subquery, for example change
insert into ... values (#YourIdField, ...)
to
insert into ... values ((select max(id) from...), ...)
I have a method on my Spring Data repository interface defined like this:
#Query("SELECT MAX(e.index) FROM entity e WHERE e.companyId = :companyId AND e.userId = :userId")
public Integer getMaxIndex(#Param("companyId") Long companyId, #Param("userId") Long userId);
The calling code looks like this:
int currIndex = 0;
Integer maxIndex = userActivityQueueRepository.getMaxIndex(companyId, user.getId());
if (null != maxIndex)
{
currIndex = maxIndex.intValue() + 1;
}
//else no records exist yet, so currIndex is 0
//create new records starting at currIndex and incrementing it along the way
The problem is that when no records exist yet, it is returning 0 and not null. So, my currIndex gets set to 1 instead of 0. Is there something I'm doing wrong in the JPQL? Is there something I can add to the JPQL so it behaves as I was expecting it would?
I'm using version 1.7.2 of Spring Data JPA with PostreSQL and EclipseLink. I turned on the logging of SQL and ran the query manually in the database, and it gives the results I expect. I just don't understand why it isn't returning null when there are no records.
For MAX function (MIN too) the result type is the type of the field, so to return null instead of 0, entity.index should be like Integer, Long but no int, long
See this table of the official documentation.
Using LINQ-to-Entities 4.0, is there a correct pattern or construct for safely implementing "if not exists then insert"?
For example, I currently have a table that tracks "user favorites" - users can add or remove articles from their list of favorites.
The underlying table is not a true many-to-many relationship, but instead tracks some additional information such as the date the favorite was added.
CREATE TABLE UserFavorite
(
FavoriteId int not null identity(1,1) primary key,
UserId int not null,
ArticleId int not null
);
CREATE UNIQUE INDEX IX_UserFavorite_1 ON UserFavorite (UserId, ArticleId);
Inserting two favorites with the same User/Article pair results in a duplicate key error, as desired.
I've currently implemented the "if not exists then insert" logic in the data layer using C#:
if (!entities.FavoriteArticles.Any(
f => f.UserId == userId &&
f.ArticleId == articleId))
{
FavoriteArticle favorite = new FavoriteArticle();
favorite.UserId = userId;
favorite.ArticleId = articleId;
favorite.DateAdded = DateTime.Now;
Entities.AddToFavoriteArticles(favorite);
Entities.SaveChanges();
}
The problem with this implementation is that it's susceptible to race conditions. For example, if a user double-clicks the "add to favorites" link two requests could be sent to the server. The first request succeeds, while the second request (the one the user sees) fails with an UpdateException wrapping a SqlException for the duplicate key error.
With T-SQL stored procedures I can use transactions with lock hints to ensure a race condition never occurs. Is there a clean method for avoiding the race condition in Entity Framework without resorting to stored procedures or blindly swallowing exceptions?
You can also write a stored procedure that uses some new tricks from sql 2005+
Use your combined unique ID (userID + articleID) in an update statement, then use the ##RowCount function to see if the row count > 0 if it's 1 (or more), the update has found a row matching your userID and ArticleID, if it's 0, then you're all clear to insert.
e.g.
Update tablex set userID = #UserID, ArticleID = #ArticleID (you could have more properties here, as long as the where holds a combined unique ID) where userID = #UserID and ArticleID = #ArticleID
if (##RowCount = 0)
Begin
Insert Into tablex ...
End
Best of all, it's all done in one call, so you don't have to first compare the data and then determine if you should insert. And of course it will stop any dulplicate inserts and won't throw any errors (gracefully?)
You could try to wrap it in a transaction combined with the 'famous' try/catch pattern:
using (var scope = new TransactionScope())
try
{
//...do your thing...
scope.Complete();
}
catch (UpdateException ex)
{
// here the second request ends up...
}