SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47570fab7567e6e9d33152a827d73e39aedf0897355fca4a6dd0ce276d25529e' 
  AND token = 'JSKDQHgUigYcqaFmb07C2le1GpKg3NJcRysTdIlfVV4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}