Script execution and memory reset in PHP - Cheat Sheet & Quick Revision

Recall & Review

beginner

What happens to variables in PHP after a script finishes executing?

All variables and data stored in memory during the script execution are cleared. PHP resets memory for the next script run.

beginner

Why does PHP reset memory after each script execution?

To ensure each script runs fresh without leftover data, preventing unexpected behavior and improving security.

beginner

Can data persist between PHP script executions without external storage?

No. PHP does not keep data in memory between runs. To persist data, you must use files, databases, or sessions.

intermediate

How does PHP handle memory during script execution?

PHP allocates memory for variables and data as the script runs, then frees all memory when the script ends.

intermediate

What is the role of the PHP garbage collector in script execution?

The garbage collector frees memory used by variables no longer referenced during script execution, helping manage memory efficiently.

What happens to PHP variables after the script finishes?

A They are saved automatically to a file

B They stay in memory for the next script

C They are cleared from memory

D They become global variables

PHP clears all variables from memory after the script ends to start fresh next time.

Which of these is needed to keep data between PHP script runs?

A Using sessions or databases

B Relying on PHP memory reset

C Declaring variables as static

D Nothing, PHP keeps data automatically

Sessions, files, or databases are needed to store data beyond one script execution.

When does PHP free memory used by variables?

A At the end of script execution

B Only when the server restarts

C When the user closes the browser

D Never, memory is permanent

PHP frees all memory used by variables when the script finishes running.

What is the PHP garbage collector's job?

A Save variables to disk automatically

B Prevent script execution

C Restart the script if memory is low

D Free memory from unused variables during script run

The garbage collector frees memory from variables no longer needed while the script runs.

Why is memory reset important in PHP script execution?

A To keep data for the next user

B To avoid leftover data causing bugs

C To slow down the server

D To save data automatically

Resetting memory prevents old data from affecting new script runs, avoiding bugs and security issues.

Explain what happens to memory and variables when a PHP script finishes running.

Think about how PHP treats data after the script ends.

Describe how you can keep data between PHP script executions despite memory reset.

Memory reset means data disappears, so what tools help keep data?