SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '177ac6a935ab9c6f7ad4c673b57cc7cbc78aa6f09469adcba7c693452b6679e0' 
  AND token = 'rKeIBQAezIln13+xo9Dw5ae9VfMYWUaZLvCM7tPmbpI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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