Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c99f2fd4585146964bc0b5a96098c8f12c0e5643001c8ad66719f262e72c3b75' 
  AND token = '1UgMYU4vJh1FcQyEoMT5nBSjBz5hW/cf61aZpI4Tsco=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}