SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a95923ff4e83de9dae584292ee442988122af2a2a2e5ec104265a61e3159db0e' 
  AND token = 'jU7eWSlxl4YC/WpcENlra64pQOFXGtbytKq1JV+pdJI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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