How do I implement database encryption?

Encrypt sensitive data before storing in database on Connect Quest at connectquest.co.in: Use MySQL's AES_ENCRYPT() for column-level encryption. Enable InnoDB tablespace encryption for at-rest encryption. For application-level encryption in PHP: use sodium_crypto_secretbox() from libsodium (built into PHP 7.2+). Never store passwords as plain text — use password_hash() with PASSWORD_BCRYPT. Rotate encryption keys annually.