HI am new to stored procedure.
Am using a dynamic sql with
select * from table into var
var is a variable.the var contains more than one value ,when i try to run the proc with inputs i get an error:
ORA-01422: exact fetch returns more than requested number of rows
Is there a way such that the variable can hold more than one row using dynamic sql.
Use collection variables:
DECLARE
TYPE tt_int IS TABLE OF INTEGER;
var tt_int;
BEGIN
SELECT id
BULK COLLECT
INTO var
FROM table;
END;
You have to bulk collect the result set into a table of type if you're going to select multiple rows.
declare
type record_type is table of <table_name>;
var_records record_type;
begin
select *
bulk collect into var_records
from <table_name>;
end;
/
See also my answer to PL SQL how to select all columns
you can also return the results to a ref cursor
set serveroutput on
DECLARE
REFEXAMPLE SYS_REFCURSOR;
VAR NUMBER ;
col varchar2(50);
BEGIN
OPEN REFEXAMPLE FOR --Here you open the cursor and fill it
SELECT *
FROM (
SELECT 1 VAR, 'a' COL FROM DUAL
UNION ALL
SELECT 2 VAR, 'b' COL FROM DUAL
UNION ALL
SELECT 3 VAR, 'c' COL FROM DUAL
UNION ALL
SELECT 4 VAR, 'd' COL FROM DUAL
UNION ALL
SELECT 5 VAR, 'e' COL FROM DUAL
) EXAMPLETABLE ;
DBMS_OUTPUT.PUT_LINE('var ' || 'col');
DBMS_OUTPUT.PUT_LINE('---------');
LOOP
FETCH REFEXAMPLE INTO VAR, col; --now loop through
EXIT WHEN REFEXAMPLE%NOTFOUND;
DBMS_OUTPUT.PUT_LINE(var || ' ' || col || ' ');
END LOOP;
CLOSE REFEXAMPLE;
end ;
/
var col
---------
1 a
2 b
3 c
4 D
5 e
You can use a table variable, which provides you with an in-memory table of your results. You declare a table variable similar to a standard variable:
declare #MyVar table (col1 col1type, col2 col2type, etc.)
Related
Is is possible to use cursor as a part of statement. Lets say i have something like this (pseudo code)
CURSOR SOURCE IS
SELECT
ID,
FLAG
FROM TABLE_OLD_A
WHERE 1=1;
TYPE t_new_a IS TABLE OF TABLE_NEW_A%ROWTYPE INDEX BY BINARY_INTEGER;
var_t_new_a t_new_a;
OPEN SOURCE;
FETCH SOURCE BULK COLLECT INTO var_t_new_a;
CLOSE SOURCE;
so far it works.
Now I would like to check if the migration from old to new is ok
WITH OLD_SOURCE AS
(
SELECT
ID,
FLAG
FROM SOURCE -> can i use cursor here in order not to copy the same select from cursor ?
)
SELECT COUNT(*) FROM TABLE_NEW_A
WHERE EXISTS
(
SELECT *
FROM OLD_SOURCE
WHERE 1=1
AND TABLE_NEW_A.ID = OLD_SOURCE.ID
AND TABLE_NEW_A.FLAG = OLD_SOURCE.FLAG
);
You can use the XML and TABLE function approach as follows to use the cursor in the query as a table as follows:
SQL> SET SERVEROUT ON
SQL> DECLARE
2 CUR SYS_REFCURSOR; -- DECLARING THE CURSOR
3 L_COUNT NUMBER;
4 BEGIN
5 --OPENING THE CURSOR
6 OPEN CUR FOR
7 SELECT 1 AS A, 5 AS B FROM DUAL UNION ALL
8 SELECT 3 AS A, 12 AS B FROM DUAL;
9
10 -- USING THE CURSOR AS A TABLE
11 SELECT MAX(B - A)
12 INTO L_COUNT
13 -- FOLLOWING CODE CONVERTS THE CURSOR TO TABLE
14 FROM (
15 SELECT EXTRACTVALUE(VALUE(SRC),'ROW/A') A,
16 EXTRACTVALUE(VALUE(SRC),'ROW/B') B
17 FROM TABLE ( XMLSEQUENCE(
18 XMLTYPE(CUR).EXTRACT('ROWSET/ROW')
19 ) ) SRC
20 ) CUR_TABLE;
21
22 DBMS_OUTPUT.PUT_LINE('Result: ' || L_COUNT);
23 END;
24 /
Result: 9
PL/SQL procedure successfully completed.
SQL>
I have a table "test_calculate" this has a column "CONN_BY" having values
column can have more than 2 number to multiply and this table may contain millions of rows , I need to get the result of the calculation from "CONN_BY" to "MVP".
I have used xmlquery for the calculation and dynamic query but these are quite slow. Is there another way which is much faster .Please suggest.
You can try the dynamic query.
Create a function which returns the calculated value and use it in your insert or select queries.
CREATE OR REPLACE FUNCTION UFN_CALCULATE (CLM_VALUE VARCHAR2)
RETURN NUMBER IS
RES_VAL NUMBER;
BEGIN
EXECUTE IMMEDIATE 'select '||CLM_VALUE||' FROM DUAL' INTO RES_VAL;
RETURN RES_VAL;
END;
You can use that function like below.
SELECT UFN_CALCULATE('.0876543 * .09876') FROM DUAL;
SELECT UFN_CALCULATE(CONN_BY) FROM YOUR_TABLE;
One option is using select ... connect by level <= regexp_count(conn_by,'[^*]+')... query for the implicit cursor within a PL/SQL code block
SQL> set serveroutput on
SQL> declare
mvp owa.nc_arr; -- numeric array to initialize each multiplication to 1 for each id value
begin
dbms_output.put_line('ID MVP');
dbms_output.put_line('--------');
for c in
(
select id,
to_number( regexp_substr(conn_by,'[^*]+',1,level) ) as nr,
level as lvl , max( level ) over ( partition by id ) as mx_lvl
from test_calculate
connect by level <= regexp_count(conn_by,'[^*]+')
and prior sys_guid() is not null
and prior conn_by = conn_by
order by id, lvl
)
loop
if c.lvl = 1 then mvp(c.id) := 1; end if;
mvp(c.id) := c.nr * mvp(c.id);
if c.lvl = c.mx_lvl then
dbms_output.put_line(c.id||' '||mvp(c.id));
end if;
end loop;
end;
/
where test_calculate is assumed to have an identity column(id)
Demo
For example I had a table named car with two column(col1,col2)
For now I would like insert some values inside the column like:
('Super car','Yellow car')
('BMW5','XL')
('Benz','AGM')
so I would like write a cursor to return ('BMW5','XL') in one single column, how do I do that?(I'm using sql developer)
I would appreciate any suggestion! Thank you!
declare
cursor mycursor is select concat(col1,col2) from car where REGEXP_LIKE(left, '^[[:digit:]]+$')
begin
for counter in mycursor
loop
dbms_output.put_line(counter.concat);
endloop;
end
You can use Concat() function in your query inside the cursor i.e.
CONCAT returns Col1 concatenated with Col2
select concat(col1,col2)
from car where <<conditions if any>>
You can write above query in Cursor like
DECLARE
CURSOR car_cursor IS select concat(col1,col2)
from car WHERE REGEXP_LIKE(col1, '[[:digit:]]');
cv_col1_col2 VARCHAR2 ;
BEGIN
OPEN car_cursor;
LOOP
FETCH car_cursor INTO cv_col1_col2;
Dbms_output.put_line('Concated Name' || cv_col1_col2)
END LOOP
CLOSE car_cursor;
END;
This is how I understood the question (though, more through by description than the title as they aren't related much).
Sample data:
SQL> create table car (col1 varchar2(10), col2 varchar2(10));
Table created.
SQL> insert into car
2 select 'Super car', 'Yellow car' from dual union all
3 select 'BMW5', 'XL' from dual union all
4 select 'Benz', 'AGM' from dual;
3 rows created.
PL/SQL code that uses a cursor FOR loop, returning concatenated col1 and col2 values for rows in which either of those columns contains a digit:
SQL> set serveroutput on;
SQL> begin
2 for cur_r in (select col1 ||' '|| col2 result
3 from car
4 where regexp_like(col1 || col2, '\d') -- any column contains
5 ) -- a digit
6 loop
7 dbms_output.put_line(cur_r.result);
8 end loop;
9 end;
10 /
BMW5 XL
PL/SQL procedure successfully completed.
SQL>
I have a table (let's name it source_tab) where I store list of all database tables that meet some criteria.
tab_name: description:
table1 some_desc1
table2 some_desc2
Now I need to execute a select statement on each of these tables and return a result as a table (I created custom TYPE). However I have a problem - when using bulk collect, only the last select statement is returned. The same issue was with open cursor. Is there any possibility to achieve this goal, another then concatenating all select statements using union all and executing it as one statement? And because I'm the begginer in sql, my second question is, is it ok to use this dynamic sql in terms of sql injection issues? Below is simplified version of my code:
CREATE OR REPLACE FUNCTION my_function RETURN newly_created_table_type IS
ret_tab_type newly_created_table_type;
BEGIN
for r in (select * from source_tab)
loop
execute immediate 'select value1, value2,''' || r.tab_name || ''' from ' || r.tab_name bulk collect into ret_tab_type;
end loop;
return ret_tab_type;
END;
I'm using Oracle 11.
In your case you are trying to populate a collection dynamically and wanted result in a single collection. In your case its not possible to do that in a single loop. Also as mentioned by #OldProgrammer, piperow would be a better solution from performance point. See below demo:
--Tables and Values:
CREATE TABLE SOURCE_TAB(TAB_NAME VARCHAR2(100), DESCRIPTION VARCHAR2(100));
/
SELECT * FROM SOURCE_TAB;
/
INSERT INTO SOURCE_TAB VALUES('table1','some_desc1');
INSERT INTO SOURCE_TAB VALUES('table2','some_desc2');
/
CREATE TABLE TABLE1(COL1 NUMBER, COL2 NUMBER);
/
INSERT INTO TABLE1 VALUES(1,2);
INSERT INTO TABLE1 VALUES(3,4);
INSERT INTO TABLE1 VALUES(5,6);
/
Select * from TABLE1;
/
CREATE TABLE TABLE2(COL1 NUMBER, COL2 NUMBER);
/
INSERT INTO TABLE2 VALUES(7,8);
INSERT INTO TABLE2 VALUES(9,10);
INSERT INTO TABLE2 VALUES(11,12);
/
Select * from TABLE2;
/
--Object Created
--UDT
CREATE OR REPLACE TYPE NEWLY_CREATED_TABLE_TYPE IS OBJECT (
VALUE1 NUMBER,
VALUE2 NUMBER
);
/
--Type of UDT
CREATE OR TYPE NEWLY_CRTD_TYP AS TABLE OF NEWLY_CREATED_TABLE_TYPE;
/
--Function:
--Function
CREATE OR REPLACE FUNCTION MY_FUNCTION
RETURN NEWLY_CRTD_TYP PIPELINED
AS
CURSOR CUR_TAB
IS
SELECT *
FROM SOURCE_TAB;
RET_TAB_TYPE NEWLY_CRTD_TYP;
BEGIN
FOR I IN CUR_TAB
LOOP
--Here i made sure that all the tables have col1 & col2 columns since you are using dynamic sql.
EXECUTE IMMEDIATE 'select NEWLY_CREATED_TABLE_TYPE(COL1, COL2) from '|| I.TAB_NAME
BULK COLLECT INTO RET_TAB_TYPE;
EXIT WHEN CUR_TAB%NOTFOUND;
FOR REC IN 1 .. RET_TAB_TYPE.COUNT
LOOP
PIPE ROW (RET_TAB_TYPE (REC) );
END LOOP;
END LOOP;
RETURN;
END;
/
Output:
SQL> Select * from table(MY_FUNCTION);
VALUE1 VALUE2
---------- ----------
1 2
3 4
5 6
7 8
9 10
11 12
6 rows selected.
May be you can combine all the queries into one using UNION ALL before execution, if the number and type of columns to be retrieved from all the tables are identical.
CREATE OR REPLACE FUNCTION my_function
RETURN newly_created_table_type
IS
ret_tab_type newly_created_table_type;
v_query VARCHAR2 (4000);
BEGIN
SELECT LISTAGG (' select VALUE1,VALUE2 FROM ' || tab_name, ' UNION ALL ')
WITHIN GROUP (ORDER BY tab_name)
INTO v_query
FROM source_tab;
EXECUTE IMMEDIATE v_query BULK COLLECT INTO ret_tab_type;
RETURN ret_tab_type;
END;
You could then use a single select statement to get all the values.
select * FROM TABLE ( my_function );
I have a table with 100 columns called like col_1, col_2, .. col_100
is there a way to select values of that columns of single into an array of 100 elements?
(Oracle 10.2)
you could just select them like:
SQL> create type foo as table of number; -- or varray, as you wish.
2 /
Type created.
SQL> select foo(l.a, l.b, l.c) foo from your_tab l;
FOO
-----------------
FOO(1, 2, 3)
etc..
Here's a brute force method. There's probably a more elegant way, or at least one that will cut down on typing. The example uses five columns rather than 100.
DECLARE
-- Change VARCHAR2(10) in the next line to your col_1 .. col_100 type
TYPE My100Array IS TABLE OF VARCHAR2(10) INDEX BY PLS_INTEGER;
myVals My100Array;
indx NUMBER;
BEGIN
SELECT 'These', 'are', 'the', 'column', 'values'
INTO myVals(1), myVals(2), myVals(3), myVals(4), myVals(5)
FROM DUAL;
FOR INDX IN 1..5 LOOP
DBMS_OUTPUT.PUT_LINE(indx || ': ' || myVals(indx));
END LOOP;
END;
Here's the output when I run this:
1: These
2: are
3: the
4: column
5: values
Of course, this will be a bit tough with 100 columns, but once you get the query out of the way you'll have the array as you want it.
Another example:
DECLARE
CURSOR c_data IS
SELECT * FROM scott.emp; -- replace emp table with your_table
TYPE t_source_tab IS TABLE OF scott.emp%ROWTYPE;
l_tab t_source_tab;
BEGIN
SELECT * BULK COLLECT INTO l_tab FROM scott.emp;
-- display values in array --
FOR i IN l_tab.FIRST ..l_tab.LAST
LOOP
DBMS_OUTPUT.PUT_LINE (l_tab(i).hiredate ||chr(9)||l_tab(i).empno ||chr(9)||l_tab(i).ename);
END LOOP;
END;
/
sounds like you want to unpivot your data..
unfortunately UNPIVOT was only added in 11g (not 10.2)
you could manually unpivot but one of the other solutions would work better i think.
However, if you were on 11g or later you could try this
create table my_table (col1 number,col2 number, col3 number);
Table MY_TABLE created.
insert into my_table values (4,5,6);
1 row inserted.
select * from my_table;
COL1 COL2 COL3
---------- ---------- ----------
4 5 6
select val from my_table unpivot ( val for col in ( col1,col2,col3));
VAL
----------
4
5
6
from there is trivial to select into an single column array
DECLARE
CURSOR c_data IS
select val from my_table unpivot ( val for col in ( col1,col2,col3));
TYPE t_source_tab IS TABLE OF c_data%ROWTYPE;
l_tab t_source_tab;
BEGIN
open c_data;
fetch c_data bulk collect into l_tab;
close c_data;
-- display values in array --
FOR i IN l_tab.FIRST ..l_tab.LAST
LOOP
DBMS_OUTPUT.PUT_LINE (l_tab(i).val);
END LOOP;
END;
/