When you load multibyte data to Oracle, data precision is measured in bytes for fixed-width files and in characters for delimited files. Make sure the target table columns are wide enough to store all the data.
Oracle supports character-oriented datatypes, such as Nchar, where the precision is measured in characters. If you use the Nchar datatype, multiply the maximum number of characters by K, where K is the maximum number of bytes a character contains in the selected target code page. This ensures that the Integration Service does not truncate data before loading the target file.