SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b53ed992f2adcee56cd597f2d45d254106aed9bf6699282dae5a81ea5cdf2d72' 
  AND token = 'O4aoX/sto5aKqRYglEu2pjJF2pCA+sbF8a4k/1G8Bj0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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