Porting from ORACLE to PostgSQL

Hello

 I need to porting many old ORACLE-oriented-SQL files and I have many
problem with this code. Sometimes the code use some types not supported
in PosgSQL like "number" or "varchar2", there fore, can I write some
type of declaration (like in c : #define alias_name name) in order to
make PosgSQL recognize these types? Or there are other solution that you
recommend to use ?

   Thank you, Gustavo

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