Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ccd1a73876719df6dd39d8529976d7023e21bfc9d6ecc205c0ee8b44af0a714' 
  AND token = 'ytChTRbYKdvtSZNj5KjFk0rpSMOb9ygUPfd+TMCUTLQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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