Modify Rows in Cursor

Question

How can i Modify rows in a Cursor?
i want to loop through cursor records and update rows on sepcific condition and update one field .and put back in the cursor.
Suggest Some way to achieve this.

Answer 1

you can only modify values of rows within the cursor when the values in the cursor are fetched and then looped through.
Once the fetch is over and you modify some values the values are not permenant. If you open the cursor again then old values will be fetched.
eg:
SQL> DECLARE
  2     CURSOR c1
  3     IS
  4        SELECT 1 AS col1, 2 AS col2
  5          FROM DUAL
  6        UNION ALL
  7        SELECT 3 AS col1, 4 AS col2
  8          FROM DUAL;
  9  BEGIN
10     FOR i IN c1
11     LOOP
12        DBMS_OUTPUT.put_line ('col1--->'||i.col1);
13        i.col1 := 10;
14        i.col2 := 20;
15        DBMS_OUTPUT.put_line ('col1--->'||i.col1);
16        DBMS_OUTPUT.put_line ('col2--->'||i.col2);
17     END LOOP;
18  END;
19  /
col1--->1
col1--->10
col2--->20
col1--->3
col1--->10
col2--->20here col1 value is modified and if you are doing further processing inside the loop for that record then 10 will avaliable and not 1. But if i again open the cursor and loop through 1 will be the value.
Hope it makes sense...
Edited by: [email protected] on May 11, 2010 5:29 AM