SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f42b66d87b55c3ff96689d533831df79265ba64536df9fcef09d248414c11c5' 
  AND token = '22tcBDlSdaZzSz+cYB7ulKTQjUNOZG318VSFUFP9K+g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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