SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd02850f41a8212adf89ae799c7c5491abef755fb9bf1b588fad9acc0d142923d' 
  AND token = 'WPUYoT8NLESWAkNX9/kI0o+LhIZblvbIZ3PB3qRCHpw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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