Data migration steps from AS400 – Oracle

Solution required Urgently
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We are planning to migrate data files (physical) from AS400 to Oracle.Please give the steps to follow for this process and any issues and problems which can occur during the process.

Table structure in Oracle will be similar to the file structure in AS400.So it will be just a dump of the physical file data.

Q1) Do we need to migrate the Logical files also(in form of indexes on tables — in oracle)

Q2) Steps involved in convertingthe packed data

Q3) Please provide any links to sites or webpages for further information on this question