Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a6763a622a4385094623ba4fa829e8de89ef701884e65e17a3f50d6fdababa96' 
  AND token = '9g6nM1wjvqMmHQ8vpzw5Y7Cxq5M1ncrnQJlxINZmwEc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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