long raw column problem

Hi there,
i have three questions on long row columns:
(1) How can I find the corresponding blocks for a long raw value and
have a look on its content ?
(2) How can I determine the size of a long raw value in a table ?
(3) How can I insert and select long raw columns in PL/SQL ?

We got Oracle 7.3.4 Workgroups-Server and i save files in a long raw column. I use DB-Tools++ from Rogue-Wave and it works fine, but i found no way (no V$ Table,...) to answer the questions above.

Any help out there? Thanks.

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