Erro!

# 1 - Can't create/write to file '/tmp/#sql_5c7c_0.MYI' (Errcode: 28)

SELECT * FROM tbdestaque ORDER BY rand() LIMIT 5;

Warning: Unknown: open(/tmp/sess_f654e3c58101e0e3e83e55cbf4eb8f8e, O_RDWR) failed: No space left on device (28) in Unknown on line 0

Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/tmp) in Unknown on line 0