SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d17f512057b672eb9cb944d684e26d04881c990e119ba31fee3f31ddb95ab28' 
  AND token = 'zZ6qqVnckctuhLab29qvUu4Rts/4OVIb4B41S/IBdtI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}