SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddeaef18ee74f12d2e8f456c4acd57ce524a6acf3e765196b338677ee45704a7' 
  AND token = 'vLTP7T5Yncp7lA73JxCZEYBqQd7fPhrsy9RWffVuejc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}