I have a custom salesforce object Installation__c and it has a custom field Product__c which is a lookup to a custom object Product__c I am trying to get the fields from the child object using these query:
public with sharing class InstallationController {
#AuraEnabled
public static List<Installation__c> getItems() {
// Perform isAccessible() checking first, then
return [SELECT Id, Name, Installation_Display_Name__c, Product__c, Status__c, (SELECT Product__c.Name FROM Product__c) FROM Installation__c];
}
}
I get the error:
Didn't understand relationship 'Product__c' in FROM part of query call. If you are attempting to use a custom relationship, be sure to append the '__r' after the custom relationship name. Please reference your WSDL or the describe call for the appropriate names.
I have tried changing the Query to
FROM Product__rand FROM Product__c__r but neither seems to work, how do I fix my query?
If you're traversing up or down a relationship hierarchy, the __c suffix becomes __r (r for 'relationship') until you finally get to the field that you're looking for (which still ends in __c if it's a custom field). So in your case, it will be
public with sharing class InstallationController {
#AuraEnabled
public static List<Installation__c> getItems() {
// Perform isAccessible() checking first, then
return [SELECT Id, Name, Installation_Display_Name__c, Product__r.Name, Status__c FROM Installation__c];
}
}
So, the change here is, for the relationship you have to use Product__r.Name
Click into the relationship on the object that has the look up. Copy the relationship name adding __r to it
This example would be Test_Drives__r
Related
I have 3 custom objects with a Master-Detail Relationship and Lookup Relationship.
CustomA__c (related CustomB__c) <-> CustomB__c <-> CustomC_c (related CustomB_cc)
I´ve built a Visualforce page with HTML table to replicate a PDF document and a Custom Controller Extension, so far so good.
But I´m just a beginner with apex coding.
The problem is that I need to replicate the document as it is, when there are no related records for CustomA__c or less then 5, it should still show the full table (the empty rows). Max. rows/related records on the document is 5, no second page needed.
Currently I´m trying to accomplisch that by using apex:variable and apex:repeat as I´ve seen some examples, but perhaps there is also another solution. For the Visualforce page I already wrote the code for the rows with data and another apeax:repeat for the empty rows.
But I´m really strugling with the controller, i know i need to iterate over the list, the code that i already wrote is also put together out of examples as i just don´t understand it yet good enough.
Any help would be appreciated! Thanks, Josip
public with sharing class CustomAController {
public CustomA__c customa{get; set;}
public CustomA__c ca{get; set;}
public CustomAController (ApexPages.StandardController controller) {
ca = (CustomA__c )controller.getRecord();
customa= [SELECT Id, Name FROM CustomA__c WHERE Id = :ApexPages.currentPage().getParameters().get('Id')];
}
public List<CustomB__c > getrelatedCustomB() {
List <CustomB__c > cbList = New List<CustomB__c >(5);
for(CustomA__c acc:[SELECT Id, Name, (SELECT Id, Name, ... , CustomCfield__r.Name FROM CustomBs__r ORDER BY Name LIMIT 5) FROM CustomA__c WHERE Id = :customa.Id]){
for(CustomB__c cb:acc.CustomBs__r)
cbList.add(cb);
}
return cbList;
}
}
You can dramatically simplify your code by writing a direct query on the child object instead of a parent-child SOQL query.
public List<CustomB__c > getrelatedCustomB() {
return [SELECT Id, Name, ... , CustomCfield__r.Name
FROM CustomB__c
WHERE CustomA__c = :customA.Id
ORDER BY Name
LIMIT 5];
}
There's no need to iterate in Apex here.
I wanted to know if the {save} method in CrudRepository do an update if it finds already the entry in the database like :
#Repository
public interface ProjectDAO extends CrudRepository<Project, Integer> {}
#Service
public class ProjectServiceImpl {
#Autowired private ProjectDAO pDAO;
public void save(Project p) { pDAO.save(p); } }
So if I call that method on an already registred entry, it'll update it if it finds a changed attribute ?
Thanks.
I wanted to know if the {save} method in CrudRepository do an update
if it finds already the entry in the database
The Spring documentation about it is not precise :
Saves a given entity. Use the returned instance for further operations
as the save operation might have changed the entity instance
completely.
But as the CrudRepository interface doesn't propose another method with an explicit naming for updating an entity, we may suppose that yes since CRUD is expected to do all CRUD operations (CREATE, READ, UPDATE, DELETE).
This supposition is confirmed by the implementation of the SimpleJpaRepository
class which is the default implementation of CrudRepository which shows that both cases are handled by the method :
#Transactional
public <S extends T> S save(S entity) {
if (entityInformation.isNew(entity)) {
em.persist(entity);
return entity;
} else {
return em.merge(entity);
}
}
So if I call that method on an already registered entry, it'll update
it if it finds a changed attribute?
It will do a merge operation in this case. So all fields are updated according to how the merging cascade and read-only option are set.
Looking at the default implemantation of CrudRepository interface
/*
* (non-Javadoc)
* #see org.springframework.data.repository.CrudRepository#save(java.lang.Object)
*/
#Transactional
public <S extends T> S save(S entity) {
if (entityInformation.isNew(entity)) {
em.persist(entity);
return entity;
} else {
return em.merge(entity);
}
}
Save method manage two situations:
-If the person Id is null (a new entity is created) then save will call persist method => insert query will be executed.
-If the person id is not null then save will call merge: fetch the existing entity from entityManagerFactory(from the 2 level cache if it doesn't exist then it will be fetched from the database) and comparing the detached entity with the managed and finally propagate the changes to the database by calling update query.
To be precise, the save(obj) method will treat obj as a new record if the id is empty (therefore will do an insert) and will treat obj as an existing record if the id is filled in (therefore will do the merge).
Why is this important?
Let's say the Project object contains an auto-generated id and also a person_id which must be unique. You make a Project object and fill in the person_id but not the id and then try to save. Hibernate will try to insert this record, since the id is empty, but if that person exists in the database already, you will get a duplicate key exception.
How to handle
Either do a findByPersonId(id) to check if the obj is in the db already, and get the id from that if it is found,
Or just try the save and catch the exception in which case you know it's in the db already and you need to get and set the id before saving.
I wanted to know if the {save} method in CrudRepository do an update if it finds already the entry in the database:
The Answer is Yes, It will update if it finds an entry:
From Spring Documentation: Herehttps://docs.spring.io/spring-data/jpa/docs/1.5.0.RELEASE/reference/html/jpa.repositories.html?
Saving an entity can be performed via the CrudRepository.save(…)-Method. It will persist or merge the given entity using the underlying JPA EntityManager. If the entity has not been persisted yet Spring Data JPA will save the entity via a call to the entityManager.persist(…)-Method, otherwise the entityManager.merge(…)-Method will be called.
In my case I had to add the id property to the Entity, and put the annotation #Id like this.
#Id
private String id;
This way when you get the object has the Id of the entity in the database, and does the Update operation instead of the Create.
I am beginning to use Dapper and love it so far. However as i venture further into complexity, i have ran into a big issue with it. The fact that you can pass an entire custom object as a parameter is great. However, when i add another custom object a a property, it no longer works as it tries to map the object as a SQL parameter. Is there any way to have it ignore custom objects that are properties of the main object being passed thru? Example below
public class CarMaker
{
public string Name { get; set; }
public Car Mycar { get; set; }
}
propery Name maps fine but property MyCar fails because it is a custom object. I will have to restructure my entire project if Dapper can't handle this which...well blows haha
Dapper extensions has a way to create custom maps, which allows you to ignore properties:
public class MyModelMapper : ClassMapper<MyModel>
{
public MyModelMapper()
{
//use a custom schema
Schema("not_dbo_schema");
//have a custom primary key
Map(x => x.ThePrimaryKey).Key(KeyType.Assigned);
//Use a different name property from database column
Map(x=> x.Foo).Column("Bar");
//Ignore this property entirely
Map(x=> x.SecretDataMan).Ignore();
//optional, map all other columns
AutoMap();
}
}
Here is a link
There is a much simpler solution to this problem.
If the property MyCar is not in the database, and it is probably not, then simple remove the {get;set;} and the "property" becomes a field and is automatically ignored by DapperExtensions. If you are actually storing this information in a database and it is a multi-valued property that is not serialized into a JSON or similar format, I think you are probably asking for complexity that you don't want. There is no sql equivalent of the object "Car", and the properties in your model must map to something that sql recognizes.
UPDATE:
If "Car" is part of a table in your database, then you can read it into the CarMaker object using Dapper's QueryMultiple.
I use it in this fashion:
dynamic reader = dbConnection.QueryMultiple("Request_s", param: new { id = id }, commandType: CommandType.StoredProcedure);
if (reader != null)
{
result = reader.Read<Models.Request>()[0] as Models.Request;
result.reviews = reader.Read<Models.Review>() as IEnumerable<Models.Review>;
}
The Request Class has a field as such:
public IEnumerable<Models.Review> reviews;
The stored procedure looks like this:
ALTER PROCEDURE [dbo].[Request_s]
(
#id int = null
)
AS
BEGIN
SELECT *
FROM [biospecimen].requests as bn
where bn.id=coalesce(#id, bn.id)
order by bn.id desc;
if #id is not null
begin
SELECT
*
FROM [biospecimen].reviews as bn
where bn.request_id = #id;
end
END
In the first read, Dapper ignores the field reviews, and in the second read, Dapper loads the information into the field. If a null set is returned, Dapper will load the field with a null set just like it will load the parent class with null contents.
The second select statement then reads the collection needed to complete the object, and Dapper stores the output as shown.
I have been implementing this in my Repository classes in situations where a target parent class has several child classes that are being displayed at the same time.
This prevents multiple trips to the database.
You can also use this approach when the target class is a child class and you need information about the parent class it is related to.
in my visualforce page i have some campaign object first user select an object then there is a multi picklist. in this picklist there is Label for all the fields user selects some fields then i have to show the value of these fields in the selected campaign object
for showing multiple picklist my apex function is
public List<SelectOption> getOptionalFields(){
Map <String, Schema.SObjectField> fieldMap= Campaign.sObjectType.getDescribe().fields.getMap();
List<SelectOption> fieldsName =new List<SelectOption>();
for(Schema.SObjectField sfield : fieldMap.Values())
{
schema.describefieldresult dfield = sfield.getDescribe();
fieldsName.add(new SelectOption(dfield.getName(),dfield.getLabel()));
}
but i have no idea how to show value for the the field
for exmple i have object instance like
Campaign c;
now i have to get value of any field whose Name is in string form.how to get corresponding value for that field.one solution is just write like
say
String fieldName;
and use multiple if
if(fieldName=='Name')
c.Name=
if(fieldName=='Id')
c.Id=
is there any other convenient method??please explain!!
You need to read about "dynamic apex". Every "concrete" sObject (like Account, Contact, custom objects) can be cast down to generic sObject (or you can use the methods directly).
Object o = c.get(fieldName);
String returnValue = String.valueOf(o);
There are some useful examples on dynamic get and set methods on Salesforce-dedicated site: https://salesforce.stackexchange.com/questions/8325/retrieving-value-using-dynamic-soql https://salesforce.stackexchange.com/questions/4193/update-a-records-using-generic-fields (second question is a bit more advanced)
You'll still need to somehow decide when to return it as String, when as number, when as date... Just experiment with it and either do some simple mapping or use describe methods to learn the actual field type...
I've got an application that reads Lead records from Salesforce via the API and I want to link the Lead Owner field to an attribute in the application. The Lead Owner field doesn't up in the list of available fields but all the custom fields do.
So, my first attempt at a solution was to create a custom field that displayed the Lead Owner name. In the SF formula editor, as far as I can tell, it doesn't display the actual data field but instead displays the ID string. Which is pretty meaningless in the context that I need it for.
alt text http://skinny.fire-storm.net/forposting/insertfield.JPG
Is there a way that we can get at the data in the object that the ID string references?
alt text http://skinny.fire-storm.net/forposting/havewant.JPG
I have the RED BOX but need the GREEN BOX.
EDIT: I can't change the application code that calls the API. I can only change salesforce. So, this is more of a salesforce superuser / formula-writer question, not a question about writing code that calls the SF API.
Salesforce allows access to related data through what they call relationship queries. Instead of joining, you specify the query like this:
System.debug([SELECT Owner.Name FROM Lead WHERE Id = '00QS00000037lvv'].Owner.Name);
Try running that in the system log, just replace the lead ID with one that you're looking at.
When accessing the data through the API, the principle is the same, your proxy objects should allow you to access Lead.Owner.Name.
EDIT:
I agree with eyescream, since you can't change the application code, creating an Apex trigger would be the best way to go here. Here's some code to get you started:
trigger Lead_UpdateOwner on Lead(before insert, before update)
{
Map<Id, String> ownerMap = new Map<Id, String>();
for (Lead lead : Trigger.new)
{
ownerMap.put(lead.OwnerId, null);
}
if (ownerMap.size() > 0)
{
for (User[] users : [SELECT Id, Name FROM User WHERE Id IN :ownerMap.keySet()])
{
for (Integer i=0; i<users.size(); i++)
{
ownerMap.put(users[i].Id, users[i].Name);
}
}
for (Lead lead : Trigger.new)
{
lead.OwnerName__c = ownerMap.get(lead.OwnerId);
}
}
}
lead.OwnerName__c would need to be the name of your custom field on the lead object that will hold the owner name. Type Text, length 121.
I had a similar problem, but wanted all the current and future User fields available. Since a custom lookup field to the User is not restricted by formula fields, I created one named
OwnerLookup
on the Opportunity and Account objects, then used a triggers to populate it on creation or edit. For example the Opportunity trigger is this:
trigger OpportunityTrigger on Opportunity (before insert, after insert, before update, after update) {
if(trigger.isBefore && trigger.isInsert) {
OpportunityTriggerHandler.newOpportunity(Trigger.old, Trigger.new);
}
else if(trigger.isAfter && trigger.isInsert){
//OpportunityTriggerHandler.futureUse(Trigger.new);
}
else if(trigger.isBefore && trigger.isUpdate){
OpportunityTriggerHandler.updateOpportunity(Trigger.new, Trigger.oldMap);
}
else if(trigger.isAfter && trigger.isUpdate){
//OpportunityTriggerHandler.futureUse(Trigger.new, Trigger.oldMap);
}
}
and the OpportunityTriggerHandler class (Apex code) is:
public with sharing class OpportunityTriggerHandler {
public static void newOpportunity( List<Opportunity> oldOpportunitys, List<Opportunity> newOpportunitys ) {
for (Opportunity opp: newOpportunitys) {
updateOwnerData( opp );
}
}
public static void updateOpportunity( List<Opportunity> oldOpportunitys, Map<Id, Opportunity> newOpportunitys ) {
for (Opportunity opp: oldOpportunitys) {
updateOwnerData( opp );
}
}
public static void updateOwnerData( Opportunity opp ) {
opp.OwnerLookup__c = opp.OwnerId;
}
}
I then create Formula fields on the Opportunity/Account objects to get to any of the owner (User) object fields, such as Oppty Owner Name formula field:
OwnerLookup__r.FirstName & " " & OwnerLookup__r.LastName
VLOOKUP function would be a good try, but
it's available only in validation rules, not in field definitions
it can be used only on custom objects and you need data from User
I'd say you need to query from your application for
SELECT Owner.FirstName, Owner.LastName FROM Lead
Other than that... some "after insert, after update" trigger that would populate your custom field when owner changes?
Just posting for completeness sake (and for the Google searches): The issue arises with any object that can be queued, not just Lead, since the source of it is that the owner can refer to either a user (as usual) or a queue object.
This can be resolved using a formula field instead of triggers, like below:
BLANKVALUE(Owner:Queue.QueueName, Owner:User.FirstName & " " & Owner:User.LastName)
Basically, the BLANKVALUE function in the formula checks whether the owner.queuename is blank, and if so gives the name of the user.