PL/SQL returning contents of a table - sql

Question

Currently working on a .Net application for viewing the contents of a table, I faced difficulties with the function that returns the contents of the table.
I use the Oracle WebLogic Server to interface comics and application, I have a function that returns a desired record of the table but I unable to adapt to it returns all records of table.
I used tables, objects I have not been able to operate the pipeline.
Here is the function that returns a record.
CREATE OR REPLACE TYPE DMD_REC AS OBJECT
(
matricule VARCHAR2(10),
nom VARCHAR2(15),
prenom VARCHAR2(15),
adresse VARCHAR2(10),
profile VARCHAR2(15),
service VARCHAR2(15),
date_dmd DATE
);
CREATE OR REPLACE FUNCTION aff_dmd
(dmd_mat IN VARCHAR2)
RETURN DMD_REC IS
dmd_found demande%rowtype;
dmd_rtn DMD_REC;
BEGIN
SELECT *
INTO dmd_found
FROM demande
WHERE demande.matricule=dmd_mat;
dmd_rtn := DMD_REC
(
dmd_found.matricule,
dmd_found.nom,
dmd_found.prenom,
dmd_found.adresse,
dmd_found.profile,
dmd_found.service,
dmd_found.date_dmd
);
RETURN dmd_rtn;
END aff_dmd;
Sorry for my english

Answer 1

Your function returns an object which fits one row. You need it to return a table of such objects.
So first you need a table type:
CREATE OR REPLACE TYPE DMD_NT AS TABLE OF DMD_REC;
Then you have to convert your function to use this new type. In the absence of any other requirements this revision will select all records in the demande table when a NULL is passed:
CREATE OR REPLACE FUNCTION aff_dmd
(dmd_mat IN VARCHAR2 := null)
RETURN DMD_NT
IS
dmd_rtn DMD_NT;
BEGIN
SELECT DMD_REC
(
d.matricule,
d.nom,
d.prenom,
d.adresse,
d.profile,
d.service,
d.date_dmd
)
BULK COLLECT INTO dmd_rtn
FROM demande
WHERE
( dmd_mat is null
or d.matricule = dmd_mat
);
RETURN dmd_rtn;
END aff_dmd;
/
The BULK COLLECT populates a collection which is stored in session memory. If your table is large (say more than 5000) this may create problems with memory resources. In which case you should consider creating a pipelined function:
CREATE OR REPLACE FUNCTION aff_dmd
(dmd_mat IN VARCHAR2 := null)
RETURN DMD_NT PIPELINED
IS
dmd_rtn DMD_NT;
BEGIN
loop
SELECT DMD_REC
(
d.matricule,
d.nom,
d.prenom,
d.adresse,
d.profile,
d.service,
d.date_dmd
)
BULK COLLECT INTO dmd_rtn limit 1000
FROM demande
WHERE
( dmd_mat is null
or d.matricule = dmd_mat
);
exit when dmd_rtn.count() = 0;
for idx in 1..dmd_rtn.count() loop
pipe row (dmd_rtn(idx));
end loop;
end loop
RETURN;
END aff_dmd;
Pipelined functions have an overhead. You should consider whether there is a way you can make it work with SYS_REFCURSOR as #BobJarvis suggested.