10 Most Common PHP Mistakes

  1. Leaving dangling array references after foreach loops
  2. Misunderstanding isset() behavior
  3. Confusion about returning by reference vs. by value
  4. Performing queries in a loop
  5. Memory usage headfakes and inefficiencies
  6. Ignoring Unicode/UTF-8 issues
  7. Assuming $_POST will always contain your POST data
  8. Thinking that PHP supports a character data type
  9. Ignoring coding standards
  10. Misusing empty()

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