Update fails when select list value isn't changed

Question

Hi Folks,
I am using htmldb_item to create a report form that is updateable. There is a checkbox in the first column and I am using a technique discussed in the forum to make sure I am getting the values from the checked rows in order to perform the updates.
However, I have noticed that if I do not change the selection in the select list, and check the "update row" checkbox, I get a "ORA-01722: invalid number" error.
I'll provide both the select and update statements and would appreciate it if someone could help me discern a solution.
== SELECT STATEMENT ==
select
htmldb_item.checkbox(1,rownum),
htmldb_item.hidden (2, p.id) ||
htmldb_item.text(3,p.project_name, 40) as project_name,
htmldb_item.select_list(4, p.gts_dependant, 'Y;Y,N;N', null, 'NO')as GTS_Dependant,
htmldb_item.select_list(5, p.gxp_relevant, 'Y;Y,N;N', null, 'NO') as GxP_Relevant,
htmldb_item.select_list_from_lov(6, u.user_first_name||' '||u.user_last_name,
'PROJECT_MANAGERS', NULL, 'NO') as project_manager
from
eprs_project p, eprs_project_monthly pm, eprs_user u
where
p.id = pm.project_id and
pm.project_manager = u.id and
to_char(record_date, 'MON YYYY') = to_char(sysdate, 'MON YYYY') and
p.program_id = :P8_SELECT_PROGRAM== SUBMIT STATEMENT ==
for i in 1..HTMLDB_APPLICATION.G_F01.COUNT
loop
update eprs_project set
project_name = HTMLDB_APPLICATION.G_F03(HTMLDB_APPLICATION.G_F01(i)),
gts_dependant = HTMLDB_APPLICATION.G_F04(HTMLDB_APPLICATION.G_F01(i)),
gxp_relevant = HTMLDB_APPLICATION.G_F05(HTMLDB_APPLICATION.G_F01(i))
where id = HTMLDB_APPLICATION.G_F02(HTMLDB_APPLICATION.G_F01(i));
update eprs_project_monthly set
project_manager = HTMLDB_APPLICATION.G_F06(HTMLDB_APPLICATION.G_F01(i))
where project_id = HTMLDB_APPLICATION.G_F02(HTMLDB_APPLICATION.G_F01(i)) and
to_char(record_date, 'MON YYYY') = to_char(SYSDATE, 'MON YYYY');
end loop;
Analysis
I've narrowed the behavior down to the Select List. The "u.user_first_name||' '||u.user_last_name" assembles the first name and last name from the user table, but must not have a value associated with it, as the rest of the names do (because they come from the application LOV "PROJECT_MANAGERS." Therefore, when the user checks the "Update Row" checkbox (rownum), there is no value associated with the selection. This would explain the invalid number error message.
If this is correct, then I am not understanding the SELECT_LIST_FROM_LOV function sufficiently. The documentation says about the p_value parameter: "This value should be a value in the p_list_values parameter." This is a small cut and paste typo because there is no p_list_values parameter, but rather a p_lov parameter. Anyway, the p_value is the default displayed value, which ideally would be one of the items from the p_lov list. It is, but not really. By that I mean, the current value is a valid name but isn't from the application LOV, per se. Therefore, I had proceeded merrily on my way believing I had fulfilled the API requirements because I had provided a "current value" and an application LOV.
The example in the user guide provides only a column name for the p_value parameter, so I don't understand how I would associate a value with the display item (from the p_value parameter) to prevent the error message from being generated. Is there a best practice for this?
Any guidance would be most gratefully appreciated.
Yours,
Petie

Answer 1

Hi. I've tried a few things to get a value into the p_value parameter.
Attempt 1:
u.user_first_name||' '||u.user_last_name;u.idAttempt 2:
'u.user_first_name||'' ''||u.user_last_name;u.id'Unfortunately, neither of these was successful. The first one wasn't valid syntax and the second was reproduced as a string literal.
Have I stumped everyone? Or am I just missing something really obvious? Any thoughts? Any workarounds? Should I create an intermediate view with the first and last names already concatanated? That wouldn't put the ID into the p_value parameter. The examples in the Users Guide don't address the value part of the "Display/Value" pairing in the Select List. They provide either a static display or a single column.
Right now, I have to put something like the following into the users manual:
"When updating core project data, you must re-select the first occurance of the project managers name from the select list. If you do not re-select the project manager name, you will receive an error when you Submit the data for update."
IMHO, this is pretty lame. Don't you agree?
Thanks for reading and any thought you can offer.
Petie