If you connect to a database with each script, consider using a persistent connection rather than a normal connection. For MySQL users, that is the difference between using mysqli_connect() with a "p:" before your host name. Persistent connections remain connected even after your script has ended, which means that the next time a script asks for a connection, it uses the one that is already open - this saves a lot time negotiating passwords and such that can otherwise be used to execute important code.
Switching to persistent connections does not require any other change than adding a "p" to your host name - the parameters are still the same.
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