# Loader

## Introduction

| A loader is a tool to transfer any database table data from a source system into a target system. You can export and import either complete data stocks or selected table data.
| ### Loader file
| The crucial element of any data transfer is the loader file as it is the exchange medium between a source and target database. It contains query conditions which lead to the data as well as to the definition of the source tables, the description and the table records.
| ### Types of loaders
| In Agile e6 there are three different loaders available for a data transfer and two different file formats (binary and xml). The selection of a loader mainly depends on two criteria: the kind of data transfer you want to do (import or export) and the different file formats of the loader file. The combination of these two criteria determine which loader can be used with which method of data transfer - as internal or external loader - since not all loaders can be used consistently for any kind of data transfer. The following section will introduce you to the different loaders according to their method of data transfer. "Internal Use" means that the loader is started directly out of an application via a specific user interface, whereas "External Use" means that any data transfer is initiated via the command line/shell.
| ### Use Cases
| #### Binary loader
| Internal Use In internal mode new UTF-8 binary loader files (*.bin) can both be exported and imported. External Use In external mode new UTF-8 binary loader files can only be imported.
| #### CTRL+V loader
| Internal Use The CTRL+V loader is used to explicitly select single records of table data from any list for the data export. Exported data can only be written into loader files of the new UTF-8 binary file format (*.bin).
| #### XML Loader
| External Use The XML loader can only be used externally. In this mode both binary and XML loader files can be exported and imported. The new loader is also used to convert all loader file formats (also previously used ASCII loader files) into any new file format.
| The XML loader writes an err file which is normally empty. If debugging or tracing is activated, the trace or debug output is written into this err-file, e.g. Loader-1234567890.err (please note that the number code is the date in miliseconds since 1970). These err-files are located in the directory <ep_root>/tmp.
| ### Loader Overview