SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6cd11be8595cb92200f7ff1b1dbae04f1fa54e1404ebcf0ae51831482027a4a1' 
  AND token = '2bBInksVWSspOs6MqqJvuRZ8uSjEgsB28vEwMgOyQxU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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