The CData Excel Add-In for Zoho CRM supports standard SQL joins like the following examples.

Inner Join

An inner join selects only rows from both tables that match the join condition:

SELECT Accounts.AccountName, Contacts.FirstName, Contacts.LastName FROM Accounts, Contacts WHERE Accounts.AccountId=Contacts.AccountId

Left Join

A left join selects all rows in the FROM table and only matching rows in the JOIN table:

SELECT Accounts.AccountName, Contacts.FirstName, Contacts.LastName FROM Accounts LEFT OUTER JOIN Contacts ON Accounts.AccountId=Contacts.AccountId