How to query all task which are having relatedto(whatId) as Account or Contact

Question

I am using an soql query to get tasks. My requirement is to get all tasks which are related account or contact object. Also few other fields inside Account or contact object whichever the object related. Is there a simple way instead of writing multiple queries.

Answer 1

Please provide more specific information next time. Generally speaking you can refer to a parent object by reference name followed with a dot. Here is an example

Select Account.Name, AccountId From Task Where Account.Name = 'John'

Here Account is the name of the reference (from task) and AccountId is the referencing field.

Answer 2

Your question is a little unclear. Are you looking for all TASKS related to any ACCOUNT or CONTACT or related to specific ACCOUNTS or CONTACTS?

If the former, try

    SELECT Id, Subject,
    FROM TASK
    WHERE
        What.Type = 'Account' OR
        Who.Type = 'Contact'

if the latter, use the IN :list syntax already suggested by Moti. The What.Type is useful, as opposed to AccountId!=null, because it will not return TASKS associated with, for example, OPPORTUNITIES (if you want that behavior, use AccountId!=null and maybe drop the Who.Type if you associate all CONTACTS with OPPORTUNITIES, as it would be redundant).

In either case, your issue will be pulling specific data from CONTACT whos, as polymorphic fields only allow access to a limited number of fields. Can't seem to find that list right now. I don't believe old SOQL supports the kind of the syntax to do that in one query--that's why SOQL polymorphism made such a bang--though I could be wrong.

Now, if you have SOQL TYPEOF available to you, you should be able to do something more interesting like:

    SELECT Id, Subject,
    TYPEOF What
        WHEN Account THEN AccountNumber
    END,
    TYPEOF Who
        WHEN Contact THEN FirstName
    END
    FROM Task
    WHERE
        What.Type = 'Account' OR
        Who.Type = 'Contact'

Answer 3

How about

select {column list] from task where parentid in (select id from account where ...) or parentid in (select id from contact where ...)

Alternatively, if you're inside Apex and already have the contact or account ids in a list (we'll use idList), you can use:

select {column list] from task where parentid in :idList