large mysql table print efficiency

[splendidbob]

Hi,
I am about to start on a web app.. The main table I will be using will be quite large in terms of records (how large I am not sure yet) - enough to cause a bit of a delay rendering the output to the screen anyway.

Basically, the entire table has to be outputted to one single page, operations will then be performed on the data, the page will be left and returned to, all things that would (if a page of a small number of results were used) result in the page being reloaded. (and the reloading delays would result) (unfortunately I cant split the data across multiple pages)

However, the usability of the app wont allow this (cant have users waiting ages after they make a small change for the entire lot to be re-rendered), so it looks like the manipulations to the data will need to be done client side (probably javascript). (there can be an initial loading period where the data is extracted from the dbase).

I am fairly sure I can do this writing the table to a layer and hiding / showing it, using innerHTML etc (so the page is never refreshed) however, before I go down this potentially painful route, I wonder if anybody else has an ideas about a simpler (pure php / mysql) method (perhaps using some clever caching or something) that would eliminate the potentially large delays if just php / mysql were used..

I doubt theres a way aside from doing some client side stuff, but it cant harm to ask 😉

thanks in advance

bob

[Roger_Ramjet]

No there is no clever way of doing this in php/mysql; except not to do it this way in the first place. The clever way to do it in php would be to paginate the output and bypass the large-output/slow rendering problem in the first place.

[tomhath]

If "large" means a few hundred rows, don't worry about the time to load the page.

If "large" means tens of thousands of rows, you have a bad design.

Either way, will you only have one user looking at the data at any given time? What happens if two users both open your application? Who's updates get saved and who's get overwritten?

[mercrapper]

You can flush your output after X number of records retrieved. This will make the page appear to load immediately while your script is still retrieving data from your database. Have a look at the flush and ob_flush functions.

There is 1 problem, IE will not render a table until it receives the </table> tag, so you will have to create a new table each time you flush your data.

You will also have to diable the mod_gzip extension.

There is much more information in the php manual.