In Crystal Reports, Oracle long field shows as Memo Field. When trying to retrieve data from this field it shows only first few characters.
It is because of using an old version (3.50.00.00) of ODBC connection.
Update the ODBC connection to 5.00 or change the data source to OLE DB then it will pull data from Memo field.
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SAP Crystal Reports XI ; SAP Crystal Reports XI R2