If you're updating Alfresco repository content outside of share, you need to do it either 1)programmatically if you have your own custom api or 2) use other connectors available if your using some third party applications like Liferay Programmatic interfaces could be through CMIS or Alfresco REST apis as mentioned here - http://docs.alfresco.com/community/concepts/dev-for-developers.html What's your use case?
Depending on what you want to update there are also easier solutions than the API's. If you just want to add or delete content the Webdav interface or a tool like CMISSync are easy to start with.
