Transforming Files - Getting Started with Talend Open Studio for Data Integration - page 37

Often, XML files will come with an XML Schema Definition ( XSD )
file so that data types can be determined directly. If you don't have
an XSD file, then some assumptions can be made from the data we
have. Although, it is important to bear in mind that sample data sets
may not give the full picture, so some caution is advised here. For
example, the metadata wizard has determined that size is an integer
based upon the data presented in the file, but we might subsequently
come across the sizes of S , M , and L , making the data type incorrect.
If you are using an XML file as the basis for the schema, ensure that it
covers all of the data types you would expect or, alternatively, edit the
schema definition as shown previously in step 5.