The CData JDBC Driver for Zoho Projects 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 t.Id, t.Name, t.Key, c.Content, c.AddedPersonName FROM Tasks t INNER JOIN TaskComments c ON t.Id = c.TaskId

Left Join

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

 SELECT t.Id, t.Name, t.Key, c.Content, c.AddedPersonName FROM Tasks t LEFT JOIN TaskComments c ON t.Id = c.TaskId