Apex_util.get_blob was not found on this server

Question

Hi All,
APEX Version: 3.1.1.00.09
Database version 11g
I am trying to create a report, with a column having a link to download the file stored as BLOB type in the database.
I performed the following steps:
*1. created custom report base on SQL Query:*
select PROGRAM_ID ,
USER_ID ,
dbms_lob.getlength(FILE_CONTENT) "FILE_CONTENT" ,
File_name
from PGMRECRT_FRMS_USRSUBMTSTATUS
[Primary Keys for the table PGMRECRT_FRMS_USRSUBMTSTATUS are :  Program_id and user_id]
*2. Configured BLOB Download Format Mask for the column "File_Content" as:*
DOWNLOAD:PGMRECRT_FRMS_USRSUBMTSTATUS:FILE_CONTENT:PROGRAM_ID:USER_ID::FILE_NAME:LST_UPD_TSTMP::attachment:Download
*3. When I run the report I get the Download link in the "File_Content" column.*
*4. When the link is clicked it throws 404 Not found Error, with the following message on the browser:*
The requested URL /pls/apex/apex_util.get_blob was not found on this server.
The Page Source contains the following
href="apex_util.get_blob?s=3261371303066053&a=101&c=2878703203169482&p=16&k1=147&k2=&ck=01786319873F8A6F1A1344A1B2A17567&rt=CR" alt="Download" title="Download 32KB"
I don't see the second Primary key being passed in the source. (User_id)
I checked the HTTP Server error log, here is the error recorded in the log file:
[Sat Jun  6 02:22:14 2009] [error] [client 141.144.160.57] [ecid: 1244280134:148.87.1.123:18724:0:2223,0] mod_plsql: /pls/apex/apex_util.get_blob HTTP-404 ORA-00900: invalid SQL statement\nORA-06512: at "SYS.WWV_DBMS_SQL", line 206\nORA-06512: at "FLOWS_030100.WWV_FLOW_DML", line 2409\nORA-06512: at "FLOWS_030100.HTMLDB_UTIL", line 1580\nORA-06512: at line 31\n
Please suggest what is the problem here and how should I go about resolving it.
I have created sample report: Visit following link: [It is SSO enabled]
https://techbpo-stage.oracle.com:4443/pls/apex/f?p=101:16
Thanks & Regards
Pooja

Answer 1

For people who are still searching for a solution:
I think you have to make sure that you select the primary key of the table containing the blob and do not use an alias for this column.
I first tried following scenario:
select my_table.pk_id, my_table.description, dbms_lob.getlength(doc.document_data) document_data
from table1 my_table
join table2 doc
on doc.pk_id = my_table.fk_doc_id;
I filled in the correct column attributes but still this resulted in the 500 error.
After some research i tried following scenario:
select my_table.pk_id, my_table.description, doc.pk_id document_id, dbms_lob.getlength(doc.document_data) document_data
from table1 my_table
join table2 doc
on doc.pk_id = my_table.fk_doc_id;
But still this resulted in the 500 error.
Finally thanks to a lucky guess I removed the alias from the doc.pk_id and added an alias for the my_table.pk_id and everything worked fine.
select my_table.pk_id table_id, my_table.description, doc.pk_id, dbms_lob.getlength(doc.document_data) document_data
from table1 my_table
join table2 doc
on doc.pk_id = my_table.fk_doc_id;
I also read something about the order in which you select the blob file, I always select it as the last column. I'm not sure if this has any influence on the result.
Regards,
Bjorn