A REF Cursor is a datatype that holds a cursor value in the same way that a VARCHAR2 variable will hold a string value.
A REF Cursor can be opened on the server and passed to the client as a unit rather than fetching one row at a time. One can use a Ref Cursor as target of an assignment, and it can be passed as parameter to other program units. Ref Cursors are opened with an
OPEN FOR statement. In most other ways they behave similar to normal cursors.
This feature was introduced with PL/SQL v2.3 (Oracle 7.3).
CREATE OR REPLACE FUNCTION func_refcur RETURN SYS_REFCURSOR AS c SYS_REFCURSOR; BEGIN OPEN c FOR select * from dual; RETURN c; END; /
Call the above function and fetch all rows from the cursor it returns:
set serveroutput on DECLARE c SYS_REFCURSOR; v VARCHAR2(1); BEGIN c := func_refcur(); -- Get ref cursor from function LOOP FETCH c into v; EXIT WHEN c%NOTFOUND; dbms_output.put_line('Value from cursor: '||v); END LOOP; END; /
When return type included then it is called strong or static structure type.
Static ref cursor supports different type of select statement but all of same structure, but not necessary that the table should be same.
This ref cursor allows us to any type of select statement irrespective of data structure .i.e any table.
is ref cursor [ return ];
for select statement . . . .;
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