SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a234ef2904730bd61482d8984fa87fe21488e1dd872bbe3419d8d930dab67db' 
  AND token = 'Md+oCED/dqdxEiu3jkA6SOGpHSYVx6WijBTMUfCukEY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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