Pls Help : Union with outer reference

Question

Hi ,
I have a simple and but at the same time complicated problem with union in my query :
Please see below sql :
The inner query with union command can not access to the outer table task_history taskHistory
I receive below error message :
**"ORA-00904: "TASKHISTORY"."TIME_STAMP": invalid identifier**
**00904. 00000 - "%s: invalid identifier"**
***Cause:**
***Action:"**
would you please help me to find out what I am doing wrong?
thanks,
select
(select max(closerDate) from
select cast(max(time_stamp) as date) as closerDate
from task_history taskHistory_2, rx_tx rxtx_2
where
taskHistory_2.task_name IN('order_entry', 'data_entry', 'data_verification','fill','product_verification' )
and rxtx_2.rx_summary_id = 65656
and taskHistory_2.rx_tx_id <= 332323
and rxtx_2.id = taskHistory_2.rx_tx_id
and rxtx_2.refill_number = 0
and taskHistory_2.task_action = 'complete'
and taskHistory_2.time_stamp < taskHistory.time_stamp
union all
select cast(max(log1.timestamp) as date) as closerDate
from AUDIT_LOG log1,
Line_item li
where li.order_entry_id= target_record_id and
TARGET_TABLE_NAME = 'OrderEntry' AND
TARGET_COLUMN_NAME = 'pickupType' AND
li.id = 3232
) from task_history taskHistory
Edited by: 969251 on Nov 2, 2012 2:10 PM

Answer 1

Welcome to the forum!
>
would you please help me to find out what I am doing wrong?
>
Well the first thing you are doing wrong is posting in the wrong forum.
This is the SQL Developer forum and, as you can see from the title, is 'Not for general SQL/PLSQL questions'.
Please repost the question in the SQL and PL/SQL forum.
PL/SQL
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{quote}
The inner query with union command can not access to the outer table task_history taskHistory
I receive below error message :
**"ORA-00904: "TASKHISTORY"."TIME_STAMP": invalid identifier**
{quote}
What else would you expect? The inner query has no knowledge of the outer query. How could it? The outer query doesn't exist until it processes both of the inner queries.
Each query of the union all needs to be a completely separate query. You should be able to run each query by itself and get a result set.
If you can't the query is invalid. Since the only table involved that has TIME_STAMP is the task_history table you need to use that table.