When exporting data from your source ECM, the exported data is divided in to 3 sections:
TDX file – Xml-based file used to store the basic information about the system and the folders structure.
STDX file – Xml-based file used to store information about documents and data items.
FileStore – A folder on the file system used to store all the exported documents from the source systems
The TDX file includes reference to the optional STDX files. Both TDX and STDX files include references to the FileStore.
TDX
The TDX file is an Xml-based file used to store the basic information about the system and the folders structure.
It is used by the Deployer to understand the structure and content of a source so that source can be loaded into a Deployer project and be used in the migration.
To accomplish this a TDX file has to maintain a structure that is predefined so the Deployer can read the data it holds into the Project. In addition to the general elements in the TDX that hold information about metadata (properties and property sets), general information about the system (export data and ecm elements) and security (permissions, entities and roles elements) the TDX also holds the Folders and Folder elements that contains some of the actual items that are to be migrated (Files/Data items) and also (when needed) a reference to a STDX file that will hold the rest of the files/data items that belong to that folder, this is done to avoid a TDX file from growing very big and affecting the performance.
STDX
The STDX file is an Xml-based file used to store additional data about all files and data items from the source content.
Just like the TDX file it has to maintain a predefined structure and has to be associated with a TDX file, this TDX file holds the basic structural information and has references (in the Folders and Folder elements) to the locations of files belonging to that folder (which will reside in the optional STDX file).
Each STDX file might hold data about files and data items from several folders however files and data items from a folder may not be split between several STDX files.