How to do a Left Inner Join in Salesfoce

Question

There are two tables in the salesforce schema

               +--------------+      +-------------+
               |   Case       |      |   User      |
               |--------------|      |-------------|
               | CaseNumber   |      |id           |
               | ContactId    |      |OwnerId      |
               | IsClosed     |      |UserName     |
               +--------------+      +-------------+

ContactId is a foreign key that maps to OwnerId (notice how foo is in both tables?)

  +-------------------------------------+        +----------------------------+
  |                     Case            |        |             User           |
  |-------------------------------------|        |----------------------------|
  |CaseNumber |  ContactId |  IsClosed  |        | id | OwnerId | UserName    |
  |                                     |        |                            |
  |1             foo          false     |        | 42   foo       bob         |
  |2             bar          true      |        | 99   bar       joe         |
  |3             foobar       false     |        | 10   foobar    sally       |
  |                                     |        |                            |
  +-------------------------------------+        +----------------------------+

I want to show the relationship between a Case and a User. (eg. bob has case 1, joe has case 2 ect..) I believe that is called a Left Inner Join. Correct me if I am wrong.

+-------------------------------------+
|                                     |
|  Case.CaseNumber | User.UserName    |
|                                     |
|     1               bob             |
|     2               joe             |
|     3               sally           |
|                                     |
+-------------------------------------+

Here is how I think the SOQL query should look.

SELECT Case.CaseNumber, User.OwnerId
FROM Case
WHERE Case.ContactId IN (SELECT User.OwnerId FROM User)

I'm am following the examples in the Salesfoce SOQL documentation http://wiki.developerforce.com/page/A_Deeper_look_at_SOQL_and_Relationship_Queries_on_Force.com

What is the correct syntax to query CaseNumber and UserName ?

Answer 1

I'm not sure if I'm following you on the schema. However, this SOQL should give you what you need.

SELECT CaseNumber, Owner.Name FROM Case

Here's a more general link that should help in writing queries like this

http://www.salesforce.com/us/developer/docs/soql_sosl/

Answer 2

Case per Contact :

List<Contact> contacts = [SELECT Id, LastName, (SELECT ID FROM Cases) FROM Contact];
System.debug(contacts[0].Cases);       //list of cases for first contact
if(contacts[0].Cases.isEmpty() == false)
{
      System.debug(contacts[0].Cases[0].CaseNumber);  //case number of first case of first contact
}

Case per User :

List<User> users = [SELECT Id, LastName, (SELECT ID FROM Cases) FROM User];
System.debug(users[0].Cases);    //list of cases for the first user
if(users[0].Cases.isEmpty() == false)
{
     System.debug(users[0].Cases[0].CaseNumber);  //case number of first case for first user
}

Other query : Only the contacts with opened cases

List<Contact> contacts = [SELECT Id, LastName, (SELECT ID FROM Cases WHERE CloseDate = null) FROM Contact WHERE Id IN (SELECT ContactId FROM Cases WHERE CloseDate = null)];

I hope that helps

Answer 3

I see that they all ready help you but I still wanted to add something...

You can always use :workbench site

https://workbench.developerforce.com/login.php?startUrl=%2Fquery.php

or force.com to test your query