Dynamic PL/SQL - Urgent help required

Question

Hi there
I am trying to write a packaged function which takes the table name and column name as arguments and build a pl/sql table which the function returns.
Please do find the code below:
Create or Replace Package Pk_valid_values
is
TYPE list_rec is record ( lc_list_desc varchar2(50));
TYPE list_tab is TABLE of list_rec
index by binary_integer;
FUNCTION Fn_fetch_values
( p_table_name varchar2,
p_column_name varchar2 )
return list_tab;
End Pk_valid_values;
Create or Replace Package Body Pk_valid_values
as
FUNCTION Fn_fetch_values
( p_table_name varchar2,
p_column_name varchar2 )
return list_tab
is
l_values Pk_valid_values.list_tab;
i binary_integer := 0;
lc_element varchar2(50);
ln_dummy number;
v_cursor integer;
lc_string varchar2(2000);
ln_count number;
BEGIN
ln_count := Pk_count_record.Count_record(p_table_name);
v_cursor := dbms_sql.open_cursor;
lc_string := 'begin select p_column_name into :felement from '||
p_table_name||' ; end;';
dbms_sql.parse( v_cursor,
lc_string,
dbms_sql.native );
dbms_sql.bind_variable( v_cursor,
':felement',
lc_element );
ln_dummy := dbms_sql.execute( v_cursor );
for i in 1..ln_count loop
dbms_sql.variable_value( v_cursor,
':felement',
lc_element );
l_values(i) := lc_element;
end loop;
dbms_sql.close_cursor( v_cursor );
return( l_values );
END Fn_fetch_values;
End Pk_valid_values;
I get an error "PLS-00382: expression is of wrong type" when I try to create this package.
Could anyone please let me know where I have gone wrong?
I have really burst my heads against this.
Thanks in advance
Rajeev

Answer 1

Hi,
I think it is that you declare a PL/SQL block, not a cursor.
Try to replace :
lc_string := 'begin select p_column_name into :felement from '||
p_table_name||' ; end;';
with :
lc_string := 'select ' || p_column_name || ' from ' || p_table_name;
Or an easier way :
declare
TYPE RefCurTyp IS REF CURSOR;
cr RefCurTyp;
lc_element varchar2(50);
begin
OPEN cr FOR 'select ' || p_column_name || ' from ' || p_table_name;
LOOP
FETCH cr INTO lc_element;
EXIT WHEN cr%NOTFOUND;
END LOOP;
CLOSE cr;
end;
/Uffe