Stored procedure and function - return table type

Question

Hello again :)
I have one simple question :) Maybe on this forum the question was asked, but I found only similar question and they didn't help me.
It's possible return in Stored Function (with StoredProcedureFunction) as result return TABLE type? Or return table type with output parametr with Stored Procedure? Or instead of the table return the db object, but it is similar problem:)
Now, I can using db types TABLES or DB OBJECTS as INPUT parameters with call stored functions or procedures, for example:
I have this simple db object:
create or replace type BUFFER_DATA_R as object( detail  VARCHAR2(4000 ))
And this simple table:
CREATE OR REPLACE TYPE BUFFER_DATA_T IS TABLE OF BUFFER_DATA_R
I create simple domain class object:
*public class DMBufferDataStruct {*
public String bufferData;
And I mapped in java with ObjectRelationalDataTypeDescriptor:
ObjectRelationalDataTypeDescriptor descriptor = new ObjectRelationalDataTypeDescriptor();
descriptor.setJavaClass(DMBufferDataStruct.class);
descriptor.setTableName("BUFFER_DATA_T");
descriptor.setStructureName("BUFFER_DATA_R");
descriptor.setPrimaryKeyFieldName("DETAIL");
descriptor.addFieldOrdering("DETAIL");
descriptor.addDirectMapping("bufferData", "DETAIL");
and join to server session ...
Well, i using this doimain class object as input parametr wih stored procedure call:
ObjectRelationalDatabaseField ordf = new ObjectRelationalDatabaseField("");
ordf.setSqlType(Types.STRUCT);
spCall.addNamedArgument(key, key,
Types.ARRAY,
"BUFFER_DATA_T",
ordf);           
query.addArgument(key);
args.add(paramsInputs.get(key));
in paramsInputs is Vector of DMBufferDataStruct...
Well, this work fine!
But I can not figure, how to return this table from output parameters of stored procedure or as a return value from stored function?
Example of exceptions:
The number of arguments provided to the query for execution does not match the number of arguments in the query definition. - return as output parameter
PLS-00382: expression is of wrong type - used as result from stored function
So, my question is: Is possible return this table type from stored procedure or function? And if YES, how can I set output argument for call?
Thx advance!
Sorry for my English! :)
Best regards, KLD

Answer 1

Your question is: what is faster PL/SQL or PL/SQL? And the answer is: it is PL/SQL of course!
As a general rule, you use a function when you return exactly one result: a number or a string or (more complex) instance of an object type or REF CURSOR or PL/SQL collection.
You use a procedure when:
a) you just do the job and return no result
b) you return multiple results - you can use multiple IN/OUT or OUT parameters
Imagine you have to write a program unit that performs a partitioned table maintenance by adding a partition.
You can implement this unit:
a) if you want return a "status code" (0 on successful completion or non-zero in case of error) then you should use a function
b) if you want no "status code" (in case of error an exception is raised that is handled outside of the program unit) then you should use a procedure
c) if you want "status code", name of tablespace where a partition was created (assume you program is so complex that it can choose different tablespaces based on metadata and free space available) and free space in that tablespace after the creation of a new partition then you should use a procedure with 3 OUT parameters.
But these are good programming practices that can be applied to (almost) any 3rd generation programming language, not only PL/SQL.