SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8b6f8c93a0d5bdcf60941b7547926b8b5a192d7a0103932636826c819974ac27' 
  AND token = 'E0ThBBsG/a3+gGaOwX9CNNo8TjYIqdcOYWjNRyApspA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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