Date format in PL/SQL Procuredure returning SQL Query

Question

We have parameters (a begin date and end date) that are entered in on a form and then passed as parameters to a report that is displayed using PL/SQL Procedure returning SQL Query. We would like the users to be able to enter the date in the format of mm/dd/yyyy but when we change the format mask on the begin and end date fields we get invalid month entered. I then went into my PL/SQL procedure and changed the code to the following
q := q || ' WHERE ' ||
'(:P41_W_BEGIN_DT IS NULL OR (:P41_W_BEGIN_DT IS NOT NULL AND
:P41_W_BEGIN_DT <= to_char(HARDWARE_INFO.WARRANTY_END_DT,''mm/dd/yyyy')))
AND
(:P41_W_END_DT IS NULL OR (:P41_W_END_DT IS NOT NULL AND :P41_W_END_DT >=
to_char(HARDWARE_INFO.WARRANTY_END_DT,''mm/dd/yyyy''))
The code is accepted but when we run the report against the parameters it seems to only be looking at the mm/dd constraint it pays no attention to the YYYY constraint. In the to_char condition if I try using single tick marks it errors out. The only way I can get the tick marks to be accepted in the code is to use 2 single tick marks ''. Any ideas on what I am doing wrong.
Thanks!

Answer 1

user520671,
You are doing the conversion in reverse. Because you're applying a function (TO_CHAR) to the columns in your predicate, you'll be negating the use of any indexes. Not prudent from a performance standpoint.
Instead, convert your input values to a date and do the comparison that way.
q := q || ' WHERE ' ||
'(:P41_W_BEGIN_DT IS NULL OR
    (:P41_W_BEGIN_DT IS NOT NULL AND to_date(:P41_W_BEGIN_DT,''MM/DD/YYYY'') <= HARDWARE_INFO.WARRANTY_END_DT))
AND
(:P41_W_END_DT IS NULL OR
    (:P41_W_END_DT IS NOT NULL AND to_date(:P41_W_END_DT,''MM/DD/YYYY'') >= HARDWARE_INFO.WARRANTY_END_DT))'Also ensure that you are truly passing in a 4-digit year.
Joel