Oracle 9i, Rel.2 - Problems with dynam statement and cursor

Question

Hello,
I have the following problem with Oracle 9i, Release 2:
I have a SQL-statement, which I create with the help of a configuration table. That means I don’t know how this statement looks at runtime. It could be look like this:
SELECT Att1, Att2, Att3
FROM Tab1
or this…
SELECT Att1, Att2
FROM Tab1
or this…
SELECT Att1
FROM Tab1
etc.
That means I don’t know in advance how many columns will be in the select-clause.
Here my code snippet until here:
v_query_str := 'SELECT ' || v_select_clause_str
|| ' FROM cb.' || v_table;
,,v_select_clause_str" willl be created dynamically
,,v_table" is as well from the config-table
Now I want to iterate through the result of the query and do further processing.
For this reason I wanted to use a cursor, iterate through the rows and save every value of each row in an own variable (but I don’t know the number of columns!!!).
But how can I open a cursor and iterate through it without knowing the number of columns???
The following code is NOT working:
TYPE t_dataColumnComp IS TABLE OF VARCHAR2(200);
a_dataColumnComp t_dataColumnComp;
--here I create the query…
v_query_str := 'SELECT ' || v_select_clause_str
|| ' FROM cb.' || v_table;
OPEN c_tempAtt FOR v_query_str;
LOOP
FETCH c_tempAtt INTO a_dataColumnComp; --THIS DON’T WORK
EXIT WHEN c_tempAtt%NOTFOUND;
FOR i IN 1..a_dataColumnComp.COUNT
LOOP
DBMS_OUTPUT.PUT_LINE(a_dataColumnComp(i));
END LOOP;
END LOOP;
CLOSE c_tempAtt; --close cursor variable
Regards
Homer

Answer 1

You will need to use DBMS_SQL to handle this since the number of columns in the result set is not known until runtime.
See here for an example of using DBMS_SQL:
http://asktom.oracle.com/pls/ask/f?p=4950:8:::::F4950_P8_DISPLAYID:235814350980