[There different size images]

This is a good method. I somtimes generate images on the fly, but this is pretty heavy for the web server. another method is to create the thumbs when you need them and store them in a cache folder. This way you dont create thumbs for images that dont get displayed.  Also try to save the original image somewhere too, just in case you need a larger photo in the future.

[[MYSQL] Group by subquery takes 2 minutes to process]

Hmm so in fact I was running 3004 query’s instead of one. That explains a lot .

 

Thanks for your clear and verry usefull explanation.

[[MYSQL] Group by subquery takes 2 minutes to process]

Thank you Barand for your input. It tuns out I did not have a index on that field yet. I added it, boosting performance to 15 seconds.

 

Then I tried your query, which runs in 0.0002 sec .

 

Thx again!.

 

 

 

[Is it possible to GROUP BY selects in UNION?]

You can try this:

SELECT id, title, url, 'table1' AS table FROM table1 WHERE publish=1 ORDER BY id DESC LIMIT 10
UNION
SELECT id, title, url, 'table2' AS table FROM table2 WHERE publish=1 ORDER BY id DESC LIMIT 10

I havent tested it, but it should return the first 10 results of both tables and add a field named table to each record to identify wich table the record came from.

[Is it possible to GROUP BY selects in UNION?]

If you want the last 20 results from both tables combined, you should use UNION. If you want the last 10 records of table 1 and the last 10 records of table 2, I would just run the 2 queries and merge the data later if needed.

[[MYSQL] Group by subquery takes 2 minutes to process]

I have a simple SQL query with a group by subquery that runs on a table with 3000 records. It takes aboud 2 minutes to run the code in PHPmyadmin. Is there a way to speed this up?

SELECT partnumber, product_id
FROM products
WHERE partnumber IN (
  SELECT partnumber
  FROM products
  GROUP BY partnumber
  HAVING count(*) > 1 )
ORDER BY partnumber;

[Php/mysql register form with paypal]

Those are a lot of questions. If you want a complete solution build for you, you should hire a programmer. But if you have a specific question concerning your code, please feel free to ask.

[Validating a Date]

the strtotime() function mostly gets it right. but I agree with mac_gyver. use a date picker or at least drop-down menus for day, month, year to be 100% safe.

[resizing images]

I dont know if there are javascript libraries that can do this, but you need something running on the client side that can process images to achieve this. I think it can be done with a java applet or flash application. but you should ask this in a flash or java forum to know for sure..

[Session_id]

It seems you dont send the GET var ID when you load the page. Try loading the page with ?id=1 at the end.

 

If you want to save the id in a session, you need to open the session at each page before you do anything else by adding session_start(); at the top of the page;

 

After that you can just get and set session vars like regulair vars. ( $_SESSION['id'] = $id; and $id = $_SESSION['id']; )

 

Good Luck