@MartinF
I always find if the joins in the metadata cannot be done, then another solution would be to use a xPath in a business rule.
Example below;
<perform_batch>
<hierarchy_select result_name="select_task_text01">
<primary_table>task_text</primary_table>
<attrs>
<attr>task_text.task_id</attr>
<attr>request.cust_prob_descr</attr>
</attrs>
<from>
<table>task</table>
<table>request</table>
</from>
<where>
<join_constraint>
<constraint>
<left_operand>task_text.task_id</left_operand>
<operator>eq</operator>
<right_operand>task.task_id</right_operand>
</constraint>
<constraint>
<left_operand>task.request_id</left_operand>
<operator>eq</operator>
<right_operand>request.request_id</right_operand>
</constraint>
</join_constraint>
<data_constraint>
<constraint>
<left_operand>task_text.task_id</left_operand>
<operator>eq</operator>
<right_operand>6475107</right_operand>
</constraint>
</data_constraint>
</where>
</hierarchy_select>
<update_request_text>
<request_text>
<request_id xpath_node="//task_text_hierarchy_select_result[@result_name='select_task_text01']/task_text/task/request_id"/>
<text_line_code>TECH</text_line_code>
<text xpath_node="//task_text_hierarchy_select_result[@result_name='select_task_text01']/task_text/task/request/cust_prob_descr" xpath_modifier=" is from the Request Table"/>
<insert/>
</request_text>
</update_request_text>
</perform_batch>
Using the record in the task_text to get to task and then request. The update in the batch will then use the data obtained on the hierarchy select to allow you to use information stored on the request in a business rule triggered from the task_text table.
There’s probably a few ways this can be done, and maybe some more graceful than this.
But I hope it helps.
Ady