SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfb156c9797f9800f05e3a24f411f04ac63a06421f89c0e63290b364a147f8c9' 
  AND token = 'BvUi+YBFW2PD7nXxudxigshBU9UNmbP/iKG4KeY7PD8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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