I couldnt find anything for this topic. I know how to connect to a mysql database and close the connection.But that means that for every script a connection should be established and closed.
Is this right and ok for big projects? About 200 concurrent users for example;
Having a single connection stored globally if this is possible but it must be (havent tried) is right? Wouldnt there be security issues or problems with getLastInsertedID ?
SO what is the best solution for handling connections;

If you're thinking large scale you might want to start thinking about an ORM to handle your object model and connections. Doctrine, Propel and Creole are 3 of the bigger ORMs in PHP.

Thank you for the reply..
But whats the logic behind them?
You didnt answer my questions just gave me some solutions somehow

Hm, I think that the question was whether multiple visits on a database-driven site would be handled well, because each php page, which requires data from the db, would initiate a new sql session as well in order to insert, update or retrieve.
The solution is called persistent link and PHP supports it.
Here is some information on it.

In theory this would minimize number of connections, however there are discussions whether this method is secure or not.
Also, many host service providers do not allow using persistent connections due to being afraid because of uncertainties how this method may be exploited by malicious users.

If I am not mistaking though, if you use includes for mysql authentication, and you do not close the connection on each querry, only one connection per session is created. In general, a user browsing your website will have 1 connection during his browsing session, until his session expires, or he closes his browser.

As for the ORM's I am not 100% sure they will minimize connection to database, unless they serve as some kind of middle-level mediator between the front end and the database. E.g. you can have multiple requests to the ORM from an on-line application, which are synthesized to a single connection from the ORM to the database. I have to read on the ORM's though...

Thank you for your answer! Persitent connections i searched for them and i see that there is a debate ...Anyways thank you for the answers.I though i was missing something..

Hi body
i want to learn php can you help me?