Hierarchical SQL query - SQLLite

I have a structure like this:

• Site
  • DocumentLibrary
    • Folder 1
      • File 1
    • Folder 2
    • Folder 3
      • File 2
      • File 3
  • DocumentLibrary 2
    • File 6
    • Folder 4
      • Folder 5
        • Folder 6
          • File 5
          • File 6

My Tables are the following:

[WEBSITE] - websiteID - websiteName

[DOCUMENT_LIBRARY] - libraryID - libraryName - websiteID

[FOLDER] - folderID - folderName - libraryID - parentFolderID

[FILE] - fileID - fileName - libraryID - folderID

My question is...Given a SiteID and a DocumentLibrary ID how can i retrieve All the folders of a document library structure? All the files of a document library structure?