PLSQL Difference Between Procedures and Functions in Oracle

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              Differences Between PLSQL Procedure & Function..
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PROCEDURE:
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1) Procedure may or may not return a value
2) Procedure Does not have a RETURN Key work
3) Procedure Cannot be called in SQL Query
4) Procedure Cannot be used in Expressesion  like A+B .. A-B..
5) Procedure Can be used for both IN , OUT & INOUT Parameters without
   Limitations.
6) Procedure can be done both DRL & DML Operations.
FUNCTION:
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1) Function Should Return A Value
2) Function will have RETURN key work to return a value.
3) Function Can be called in SQL Query.
4) Function Can be Used in Expression..
5) Function Can be used only IN Parameter But OUT & INPUT Parameter will be
   Used with some limitations.
6) Function Can be used only for DRL (Select), But DML can be allowed with
   Some Limitations and it wont be suggested..