There is a difference between custom BOs (.bo) and extenions to SAP BOs (.xbo).
For custom BOs all data types are restricted to 255 characters on the database (see the documentation section 7.2.7 Basic Data Types, "Variables of unrestricted length, for example, variables of the LANGUAGEINDEPENDENT_Text data type, are truncated at a length of 255 characters as soon as they are saved to the database. For texts that are longer than 255 characters, use the TextCollection dependent object.")
For BO extension, the Text or LANGUAGEINDEPENDENT_EXTENDED_Text datatype is not restricted in length. In fact the documentation does not reflect this difference. I will ask my colleague to add this.
Best regards,
Thomas
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