How do you determine if an image is invalid?
You may be able to apply this criteria to your SELECT statement
without any additional fields.
On Jan 27, 2:50 pm, Takuo SHIONO <[EMAIL PROTECTED]> wrote:
> Hello,
>
> If you do not want to keep unnecessary fields for almost 50% of images,
> you can use image_link table, which contains 3 fields(image_id, next_id,
> previous_id). You maintain this table in afterSave function only when
> you edit or add valid images.
>
> You can define the HASONE relationship between image model and
> image_link model. I think this makes your code smart like below:
>
> // Controller
> $image = $this->Image->findById($id);
> $this->set('image', $image);
>
> // View
> <?php echo $html->link('next', '/images/view/'.
> $image['ImageLink']['next_index']); ?>
>
> Best Wishes,
>
> Takuo Shiono
>
> Novice Programmer wrote:
> > Hello Shiono,
>
> > When i tried to add the two fields, it seemed like an overhead to me because
> > almost 50% of the images would be invalid, so adding two fields to database
> > design will lead to addition of these fields in these invalid images as well
> > and hence occupy more space in database. I want to avoid that if possible.
>
> > Thanks.
>
> > On 1/27/08, Takuo SHIONO <[EMAIL PROTECTED]> wrote:
>
> >> Hello,
>
> >> I often use solution 1. I think this solution can be applied in almost
> >> all cases. However I have another solution. How about this:
>
> >> 1. add 2 fields (prev_valid_index and next_valid_index) in table.
> >> 2. update these fields in afterSave function.
> >> 3. show image with the next/previous link according to the fields.
>
> >> Best Wishes,
>
> >> Takuo Shiono
>
> >> Novice Programmer wrote:
> >>> Though this is less of a database question. but i am still posting it
> >> here
> >>> since I think we can discuss the design as well.. :).
>
> >>> I am maintaining a adresses of images stored on my filesystem in a
> >> database.
> >>> I have designed a system to show those images to the user. This
> >> interface
> >>> has the next and previous button as well. When user clicks on next he
> >> goes
> >>> to the *next valid image*. Note the difference here. I have to show only
> >>> valid images. This means that all the images in the database are not to
> >> be
> >>> shown. Lets consider an example. Say that my database consists of
> >> following
> >>> images:
>
> >>> 1. Image1(Valid)
> >>> 2. Image2(InValid)
> >>> 3 Image3(Invalid)
> >>> 4. Image4(Valid)
>
> >>> so when user is viewing image 1 and clicks on next he goes to image4
> >>> directly even though image2 is stored in the next index on the database.
> >> I
> >>> have thought of following solutions but none of them are appealing me:
>
> >>> 1. Maintain a variable which tells the index of next valid image.
> >> Maintain a
> >>> variable which tells me the index of last valid image and when next
> >> valid
> >>> image comes, update the index of the last valid image with this new
> >> image.
> >>> Similarly maintain the previous variable.
> >>> 2. I am storing time stamp along with the images. On clicking next, I
> >> load
> >>> the image having the most recent time stamp after this image. but still
> >> I
> >>> dont like this query as this may be slow.
>
> >>> Please help.
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups "Cake
PHP" group.
To post to this group, send email to cake-php@googlegroups.com
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at
http://groups.google.com/group/cake-php?hl=en
-~----------~----~----~----~------~----~------~--~---
