We're implementing a coupon program. The coupons are unique codes and are related to an existing customer and stored in a custom field on the Account.
When a Lead is created due to being referred using one of the unique coupons, the unique coupon is saved in a custom field on the Lead. I need to access the associated Account Id of the unique coupon.
I could do this by creating a trigger on lead insert and then query accounts looking for unique coupon. My concern with this approach is having a trigger and query on every lead created; seems this would not be good pratice - using so much resources for a rare situation
Is there another (better) approach; lookup?
Thanks
If you build the trigger correctly there should be no concern about resources. But it really depends on what you're trying to do with the Account data, I don't know the architecture though so you will need to give more details
Related
I have two objects - "Account" and "Appointment". I'm trying to pull the value of the field "Status" from the "Appointment" object where "Account.Initial_Date" matches "Appointment.Date_Time". I initially tried making a new field in the "Account" object to return a text field and see if maybe it would return the first value:
Appointment__c.Status__c
Which results in the error:
"Field Appointment__c does not exist. Check spelling."
I was told that it's too difficult to link from "Appointment" to "Account" because there can be multiple appointments per account, which is why I'm trying to link based on the date fields. My next attempt was using VLOOKUP, but I read that this only works between custom objects, and I think I'm working with standard objects here... what kind of solution should I be looking for?
Adding the tag apex here in case this can only be achieved via a script of some sort - if that's the case, I'll make attempt via that.
I was told that it's too difficult to link from "Appointment" to "Account" because there can be multiple appointments per account
This is incorrect. That relationship appears to be exactly the same as that between Contact and Account - one Contact, many Accounts. It's a very common relationship pattern in Salesforce.
If an Appointment is logically related to an Account, it should have a relationship field referencing the Account object to which it is related.
However, having a one-to-many relationship does not mean you can trivially represent specific data points from the many side to the one side. The native tool to do so is the Roll-Up Summary Field, but it does not apply to your use case.
There's really three ways to implement your objective, which is essentially implementing a variant of a roll-up summary. VLOOKUP(), which works only in Validation Rules, does not apply here.
Write two Apex triggers (one on Account and one on Appointment) to react to all changes that would influence what value should appear in the Account__c.Status__c field.
Write equivalent Process and Flow declarative automation, which cannot get 100% of the way there because Process Builder and Flow cannot react to delete events.
Use the free and open source Declarative Lookup Rollup Summaries application to define a roll-up summary. DLRS can populate a field from the child object (Appointment) to the parent (Account) based on a sorting by another field (Date_Time__c).
Lets say I have a number of (less than fifty) entities in my datamodel and I need to store who owns this entity for security reasons. I need to be able to decide on each request if the user doing a specific action on a resource is allowed to do that (who is doing what on which resource). And for this the resource ownership is needed.
I can think of several different ways to do this. One is that in each table I can have a foreing key pointing to the owner. One downside with this solution is that in code I need to look at each individual table to find out the ownership. Each time there is a new table added I would need to update the code to look in that new table.
Another solution could be to treat every specific entity as a generic resource, a resource that has an ownership. And store that ownership in one single table. I could even do that without any foreign key relationship and deal with it in code to keep the resource table in sync and e.g. make sure that each new entry in any table has a corresponding record in the "resource" table. One obvious downside would be that there will be a lot of records in this table. The benefit would be that there is one single place to go to to find the ownership.
So what would be the preferred way? Would there be a performance problem with storing the ownership in one table, given there might be in the range of hundreds of thousands of records (possibly even millions) in it eventually? What about the cost of preserving lots of foreign key constraints? Is there a better way of solving this?
Thanks
You're working in an object oriented language. Inheritance is perfect to solve this problem.
Depending on if you use Code First, or DB First, your approach will be slightly different, but boils down to this:
Make and abstract class, you can call it something like 'OwnableEntity'. In essence, you put your foreign key and navigation property in there.
Inherit all your entities from this 'OwnableEntity'
Make sure that your inheritance mapping in EF is correct (in this case, TPC inheritance mapping is what you will probably want to use)
From now on, you can write your 'check ownership' logic against 'OwnableEntity', and it will be OK for every entity you implement later on.
I want to be as efficient as possible and plan properly. Since read and write costs are important when using Google App Engine, I want to be sure to minimize those. I'm not understanding the "key" concept in the datastore. What I want to know is would it be more efficient to fetch an entity by its key, considering I know what it is, than by fetching by some kind of filter?
Say I have a model called User and a user has an array(list) of commentIds. Now I want to get all this user's comments. I have two options:
The user's array of commentId's is an array of keys, where each key is a key to a Comment entity. Since I have all the keys, I can just fetch all the comments by their keys.
The user's array of commentId's are custom made identifiers by me, in this case let's just say that they're auto-incrementing regular integers, and each comment in the datastore has a unique commentIntegerId. So now if I wanted to get all the comments, I'd do a filtered fetch based on all comments with ID that is in my array of ids.
Which implementation would be more efficient, and why?
Fetching by key is the fastest way to get an entity from the datastore since it the most direct operation and doesn't need to go thru index lookup.
Each time you create an entry (unless you specified key_name) the app engine will generate a unique (per parent entity) numeric id, you should use that as ids for your comments.
You should design a NoSql database (= GAE Datastore) based on usage patterns:
If you need to get all user's comments at once and never need to get one or some of them based on some criteria (e.g. query them), than the most efficient way, in terms of speed and cost would be to serialize all comments as a binary blob inside an entity (or save it to Blobstore).
But I guess this is not the case, as comments are usually tied to both users and to posts, right? In this case above advice would not be viable.
To answer you title question: get by key is always faster then query by a property, because query first goes through index to satisfy the property condition, where it gets the key, then it does the get with this key.
I want to create a multi-select Contact Lookup.
What i want :
When user clicks on a lookup then he should be able to select multiple contacts from that.
What i have done:
I have created an object and a field inside that object using both
"Lookup" and
"MasterDetail Relationship" and
"Junction Object"
When i try to use this Field for any input text/Field then it always provides an option to select only one value from lookup but i want to have an option to select multiple.
Even in the Junction object i have created 2 master-detail relationships still lookup allows only one value to be selected.Moreover it makes the field mandatory which i don't want.
Links that i followed:
http://success.salesforce.com/questionDetail?qId=a1X30000000Hl5dEAC
https://ap1.salesforce.com/help/doc/user_ed.jsp?loc=help§ion=help&hash=topic-title&target=relationships_manytomany.htm
Can anybody suggest me how to do this.
Its same as we use Email CC/BCC under Send Email option for any Lead.
Even you use a junction object a lookup is just that, it references (looks up to) one other record: when you create a record on the junction object you still have to set each lookup individually and you're still creating only one record.
Master Detail relationships are essentially lookups on steroids, one object becomes the child of the other and will be deleted if the parent object is deleted, they're not going to provide an interface to lookup to many records at once.
If you're not a developer then your best bet is to either just create on junction object record at a time, or look into using dataloader. You could prepare your data in Excel or similar and then upload all the records into Salesforce in one go.
If you are a developer, or have developers at your disposal, then what we've done in the past is create a Visualforce page to do the job. So if, for example, you wanted to link a bunch of contacts up to an Account, we'd have a single account lookup field on the page, then some search fields relating to fields on the contact. Using a SOQL query you can then find all contacts matching the search parameters and display them in a list, where you may want to provide checkboxes to allow the user to select the contacts they want. Then it's just a case of looping through the selected contacts, setting their Account field to be the chosen account.
There are areas in Salesforce (such as the send Email functionality you mentioned) where it's clear to see that bespoke work has been done to fulfil a specific task — another instance of what you want is in the area where you can manage campaign members. This is the model I've copied in the past when implementing a Visualforce page as described.
Good luck!
For adding multiple junction objects at one time, the only solution we have found is a custom Visualforce page, as described by LaceySnr.
For a slightly different problem, where we need to assign many of object B to object A, We have trained our users to do this with a view on object B. We are assigning Billing Accounts (B) to Payment Offices (A). The view on Billing Account has check boxes on the left side. The user checks the Billing Accounts to be assigned, then double-clicks on the Payment Office field on any of the checked rows. A pop-up asks if you want to update only the single row or all checked rows. By selecting 'all checked rows', the update is done to all of them.
The view is created by the user, who enters the selection criteria (name, address, state, etc.). All user-created views are visible only to them.
I'm working on a multi-user internet database-driven website with SQL Server 2008 / LinqToSQL / custom-made repositories as the DAL. I have run across a normalization problem which can lead to an inconsistent database state if exploited correctly and I am wondering how to deal with the problem.
The problem: Several different companies have access to my website. They should be able to track their Projects and Clients at my website. Some (but not all) of the projects should be assignable to clients.
This results in the following database schema:
**Companies:**
ID
CompanyName
**Clients:**
ID
CompanyID (not nullable)
FirstName
LastName
**Projects:**
ID
CompanyID (not nullable)
ClientID (nullable)
ProjectName
This leads to the following relationships:
Companies-Clients (1:n)
Companies-Projects (1:n)
Clients-Projects(1:n)
Now, if a user is malicious, he might for example insert a Project with his own CompanyID, but with a ClientID belonging to another user, leaving the database in an inconsistent state.
The problem occurs in a similar fashion all over my database schema, so I'd like to solve this in a generic way if any possible. I had the following two ideas:
Check for database writes that might lead to inconsistencies in the DAL. This would be generic, but requires some additional database queries before an update and create queries are performed, so it will result in less performance.
Create an additional table for the clients-Projects relationship and make sure the relationships created this way are consistent. This also requires some additional select queries, but far less than in the first case. On the other hand it is not generic, so it is easier to miss something in the long run, especially when adding more tables / dependencies to the database.
What would you do? Is there any better solution I missed?
Edit: You might wonder why the Projects table has a CompanyID. This is because I want users to be able to add projects with and without clients. I need to keep track of which company (and therefore which website user) a clientless project belongs to, which is why a project needs a CompanyID.
I'd go with with the latter, having one or more tables that define the allowable relationships between entities.
Note, there's no circularity in the references you have, so the title is misleading.
What you have is the possibility of conflicting data, that's different.
Why do you have "CompanyID" in the project table? The ID of the company involved is implicitly given by the client you link to. You don't need it.
Remove that column and you've removed your problem.
Additionally, what is the purpose of the "name" column in the client table? Can you have a client with one name, differing from the name of the company?
Or is "client" the person at that company?
Edit: Ok with the clarification about projects without companies, I would separate out the references, but you're not going to get rid of the problem you're describing without constraints that prevent multiple references being made.
A simple constraint for your existing tables would be that not both the CompanyID and ClientID fields of the project row could be non-null at the same time.
If you want to use the table like this and avoid the all the new queries just put triggers on the table and when user tries to insert row with wrong data the trigger with stop him.
Best Regards,
Iordan
My first thought would be to create a special client record for each company with name "No client". Then eliminate the CompanyId from the Project table, and if a project has no client, use the "No client" record rather than a "normal" client record. If processing of such no-client's is special, add a flag to the no-client record to explicitly identify it. (I'd hate to rely on the name being "No Client" or something like that -- too fuzzy.)
Then there would be no way to store inconsistent data so the problem would go away.
In the end I implemented a completely generic solution which solves my problem without much runtime overhead and without requiring any changes to the database. I'll describe it here in case someone else has the same problem.
First off, the approach only works because the only table that other tables are referencing through multiple paths is the Companies table. Since this is the case in my database, I only have to check whether all n:1 referenced entities of each entity that is to be created / updated / deleted are referencing the same company (or no company at all).
I am enforcing this by deriving all of my Linq entities from one of the following types:
SingleReferenceEntityBase - The norm. Only checks (via reflection) if there really is only one reference (no matter if transitive or intransitive) to the Companies table. If this is the case, the references to the companies table cannot become inconsistent.
MultiReferenceEntityBase - For special cases such as the Projects table above. Asks all directly referenced entities what company ID they are referencing. Raises an exception if there is an inconsistency. This costs me a few select queries per CRUD operation, but since MultiReferenceEntities are much rarer than SingleReferenceEntities, this is negligible.
Both of these types implement a "CheckReferences" and I am calling it whenever the linq entity is written to the database by partially implementing the OnValidate(System.Data.Linq.ChangeAction action) method which is automatically generated for all Linq entities.