TO_char ------------- To_date

Question

Asalam and hello every one...
i am having a bit concept problem.. i have a condition that
my created_date should be greather then and equal to 26-nov-2009 and it should return 605 records
now when i am doing it with following method its returning 31 rows
where to_char(a.created, 'dd-mon-rr') >= '26-nov-09'
but if i do it with this method its working perfectly fine..
where to_date(a.created, 'dd-mon-rr') >= '26-nov-09'
now i want to know why its not returning all records when i am using to_char function

Answer 1

Because you're comparing apples with bananas.
Let's assume your CREATED column is of DATE datatype (you didn't mention that at all here).
Then your first predicate would be:
where to_char(a.created, 'dd-mon-rr') >= to_char(to_date('26-nov-09','dd-mon-rr'), 'dd-mon-rr')And the second one:
where  a.created >= to_date('26-nov-09', 'dd-mon-rr')Always compare DATES to DATES
Always compare STRINGS to STRINGS
Never compare STRINGS to DATES etc..
If your CREATED column is not of DATE datatype, then you need to adjust your design, change the table.
I wonder why, in the year 2010, you still use only 2 digits for the year part, instead of 4?