Run query dynamically in stored procedure in Oracle - oracle

Question

Select all the tables of database where column match than pass table name to next query using loop. If column name and column values matches than return true and exist for loop using a stored procedure:
CREATE OR REPLACE PROCEDURE TEST
(
NAME IN VARCHAR2 ,
ID IN NUMBER,
RE OUT SYS_REFCURSOR
) AS
BEGIN
OPEN RE FOR SELECT A.TABLE_NAME FROM
user_tables A JOIN user_tab_columns C
ON C.TABLE_NAME = A.TABLE_NAME
WHERE C.COLUMN_NAME = NAME;
FOR RE IN LOOP
v_Sql := 'SELECT COUNT(*) FROM '|| LOOP.TABLE_NAME || 'WHERE COLUMN_NAME =
ID';
EXECUTE IMMEDIATE v_Sql
IF v_Sql%ROWCOUNT > 0 THEN
return true;
EXIT
END LOOP;
END TEST;
For more understanding the problem
//Get all the tables of database where campus_id is exist in any table of
database
Campus, Class, Section (3 tables found)
Apply forloop on the records
Select count(campus_id) as total from (table name using loop) where campus_id = 1(value
pass)
if(total > 0){
Exist for loop and return true
}
else{
Again iterate the loop to next value
}

Answer 1

What you described doesn't make much sense. If there are several tables that contain a column you're checking and you exit the loop as soon as you find the first one, what about the rest of them?
Here's what I'd do, see if it helps. I'll create a function (not a procedure) that returns a table. In order to do that, I'll create type(s) first:
SQL> create or replace type t_record as object (tn varchar2(30), cnt number);
2 /
Type created.
SQL> create or replace type t_table as table of t_record;
2 /
Type created.
SQL>
The function:
in a cursor FOR loop I'm selecting tables that contain that column
L_STR is used to compose the SELECT statement
DBMS_OUTPUT.PUT_LINE is used to display it first, so that I could visually check whether it is correctly set or not.
if it is, I'm running it with the EXECUTE IMMEDIATE
the result is stored into a table type and returned to the caller
SQL> create or replace function f_colname
2 (par_column_name in varchar2,
3 par_column_value in varchar2
4 )
5 return t_table
6 is
7 retval t_table := t_table();
8 l_str varchar2(200);
9 l_cnt number;
10 begin
11 for cur_r in (select table_name
12 from user_tab_columns
13 where column_name = par_column_name
14 )
15 loop
16 l_str := 'select count(*) from ' || cur_r.table_name ||
17 ' where ' || par_column_name || ' = ' ||
18 chr(39) || par_column_value || chr(39);
19 -- Display l_str first, to make sure that it is OK:
20 -- dbms_output.put_line(l_str);
21 execute immediate l_str into l_cnt;
22 retval.extend;
23 retval(retval.count) := t_record(cur_r.table_name, l_cnt);
24 end loop;
25 return retval;
26 end;
27 /
Function created.
Testing:
SQL> select * from table (f_colname('DEPTNO', '10'));
TN CNT
------------------------------ ----------
TEST_201812 1
DEPT 1
EMP 3
SQL> select * from table (f_colname('ENAME', 'KING'));
TN CNT
------------------------------ ----------
EMP 1
BONUS 1
SQL>
That won't work properly for some datatypes (such as DATE) and will have to be adjusted, if necessary.
[EDIT: after you edited the question]
OK then, that's even simpler. It should still be a function (that returns a Boolean, as you said that - in case that something's being found - you want to return TRUE). Code is pretty much similar to the previous function.
SQL> create or replace function f_colname
2 (par_column_name in varchar2,
3 par_column_value in varchar2
4 )
5 return boolean
6 is
7 l_str varchar2(200);
8 l_cnt number;
9 retval boolean := false;
10 begin
11 for cur_r in (select table_name
12 from user_tab_columns
13 where column_name = par_column_name
14 )
15 loop
16 l_str := 'select count(*) from ' || cur_r.table_name ||
17 ' where ' || par_column_name || ' = ' ||
18 chr(39) || par_column_value || chr(39);
19 -- Display l_str first, to make sure that it is OK:
20 -- dbms_output.put_line(l_str);
21 execute immediate l_str into l_cnt;
22 if l_cnt > 0 then
23 retval := true;
24 exit;
25 end if;
26 end loop;
27 return retval;
28 end;
29 /
Function created.
Testing: as you can't return Boolean at SQL layer, you have to use an anonymous PL/SQL block, as follows:
SQL> declare
2 l_ret boolean;
3 begin
4 if f_colname('DEPTNO', '15') then
5 dbms_output.put_line('It exists');
6 else
7 dbms_output.put_line('It does not exist');
8 end if;
9 end;
10 /
It does not exist
PL/SQL procedure successfully completed.
SQL>