SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5cdd760ed17261dc2960e2fe38a96b1acd2c802ff1123fc0d32f7d8ff4b258f0' 
  AND token = 'ZCgSWorOYxDuMsrFHlA4UygsBqIi/CAgHNdRnrzChX4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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