My situation:
I have a table named Table1. It has lots of columns, one of them is Column1. I don't know the other columns, they may even change sometimes.
There is a strongly typed ref cursor type which returns Table1%rowtype, named cur_Table1.
I have a stored procedure named SP1 which has an out parameter of type cur_Table1. I'm calling this SP1 stored procedure from another database that only sees this stored procedure, but not the table or the type itself.
How do I select only Column1 from the returned cursor?
I know I can fetch into a record or as many variables as the cursor has columns, but I only know of one column's existence so I can't declare the complete record or correct number of variables.
You can do this with DBMS_SQL, but it ain't pretty.
Table and sample data (COLUMN1 has the numbers 1 - 10):
create table table1(column1 number, column2 date, column3 varchar2(1000), column4 clob);
insert into table1
select level, sysdate, level, level from dual connect by level <= 10;
commit;
Package with a procedure that opens a ref cursor and selects everything:
create or replace package test_pkg is
type cur_Table1 is ref cursor return table1%rowtype;
procedure sp1(p_cursor in out cur_table1);
end;
/
create or replace package body test_pkg is
procedure sp1(p_cursor in out cur_table1) is
begin
open p_cursor for select column1, column2, column3, column4 from table1;
end;
end;
/
PL/SQL block that reads COLUMN1 data from the ref cursor:
--Basic steps are: call procedure, convert cursor, describe and find columns,
--then fetch rows and retrieve column values.
--
--Each possible data type for COLUMN1 needs to be added here.
--Currently only NUMBER is supported.
declare
v_cursor sys_refcursor;
v_cursor_number number;
v_columns number;
v_desc_tab dbms_sql.desc_tab;
v_position number;
v_typecode number;
v_number_value number;
begin
--Call procedure to open cursor
test_pkg.sp1(v_cursor);
--Convert cursor to DBMS_SQL cursor
v_cursor_number := dbms_sql.to_cursor_number(rc => v_cursor);
--Get information on the columns
dbms_sql.describe_columns(v_cursor_number, v_columns, v_desc_tab);
--Loop through all the columns, find COLUMN1 position and type
for i in 1 .. v_desc_tab.count loop
if v_desc_tab(i).col_name = 'COLUMN1' then
v_position := i;
v_typecode := v_desc_tab(i).col_type;
--Pick COLUMN1 to be selected.
if v_typecode = dbms_types.typecode_number then
dbms_sql.define_column(v_cursor_number, i, v_number_value);
--...repeat for every possible type.
end if;
end if;
end loop;
--Fetch all the rows, then get the relevant column value and print it
while dbms_sql.fetch_rows(v_cursor_number) > 0 loop
if v_typecode = dbms_types.typecode_number then
dbms_sql.column_value(v_cursor_number, v_position, v_number_value);
dbms_output.put_line('Value: '||v_number_value);
--...repeat for every possible type
end if;
end loop;
end;
/
Given the original question, jonearles's answer is still correct, so I'll leave it marked as such, but I ended up doing something completely different and much better.
The problem was/is that I have no control over SP1's database, I just have to call it from somewhere else as a 3rd party client. Now I managed to get permission to see not only SP, but also the type of the cursor. I still don't see the table but now there is a much cleaner solution:
In the other database I have been granted access to see this type now:
type cur_Table1 is ref cursor return Table1%rowtype;
So in my database I can do this now:
mycursor OtherDB.cur_Table1;
myrecord mycursor%rowtype;
...
OtherDB.SP1(mycursor);
fetch mycursor into myrecord;
dbms_output.put_line(myrecord.Column1);
See, I still don't need any access to the table, I see the cursor only. The key is that the magical %rowtype works for cursors as well, not just tables. It doesn't work on a sys_refcursor, but it does on a strongly typed one. Given this code, I don't have to care if anything changes on the other side, I don't have to define all the columns or records at all, I just specify the one column I'm interested in.
I really love this OOP attitude about Oracle.
Don't know if it's an option or not, but wouldn't a better solution be to create a function that returns the specific value you're looking for? That avoids the overhead of sending the extra data. Alternatively, you could define a cursor with a set of known fields in it that both parties know about.
Related
The question seems easy. I have built a package, where there is a quite massive cursor, let's say on all invoices of my company for the whole year.
CURSOR c_invoices(p_year IN INTEGER) IS
SELECT all_invoices.invoicenumber,
all_invoices.invoicedate,
all_invoices.customernumber
FROM all_invoices
WHERE all_invoices.year = p_year
;
After opening it and using a LOOP statement, I want to get some data from another table (forbidden_customers), but only if the customer is in this very last table.
What I'd like to do, is to open another cursor (or a SELECT ?) at the very beginning of my package, browsing the whole table(forbidden_customers), and then getting to the corresponding record when in my invoices LOOP.
So, something like :
CURSOR c_forbidden_customers IS
SELECT forbidden_customers.customernumber,
forbidden_customers.customeradress
FROM forbidden_customers
;
And then :
OPEN c_invoices(v_year);
LOOP FETCH c_invoices INTO invoices_cursor;
BEGIN
EXIT WHEN c_invoices%NOTFOUND;
*IF invoices_cursor.customernumber IS FOUND IN c_forbidden_customers ...
THEN ...*
This is what I do meanwhile (I know it is bad):
SELECT COUNT(*)
INTO v_exist /*INTEGER*/
FROM forbidden_customers
WHERE forbidden_customers.customernumber= p_customernumber
IF v_exist <> 0
THEN...
I tried to make it as clear as possible. Thank you for your time
Don't do it twice; join both tables in the same cursor and use it. Also, if you switch to a cursor FOR loop, you'll save yourself from some typing as Oracle will do most of boring stuff for you (declaring cursor variable, opening the cursor, closing it, exiting the loop ...):
create or replace procedure p_test (p_year in integer) is
begin
for c_invoices in
(select a.invoicenumber,
a.invoicedate,
a.customernumber,
c.customeraddress
from all_invoices a join forbidden_customers c on c.customernumber = a.customernumber
where a.year = p_year)
loop
-- do something
end loop;
end;
If the table forbidden_customers is not large and it will fit oracle's session memory, you can use a pl/sql table to store all id's from forbidden_customers and check it later. The check is done in memory only, so it is much faster than any regular select.
create table all_invoices
(id number,
year number,
customer_number number);
create table forbidden_customers
(customer_number number);
CREATE OR REPLACE TYPE t_number_table IS TABLE OF number
/
CREATE OR REPLACE PROCEDURE test23
IS
forbidden_customers_list t_number_table;
CURSOR c_invoices (p_year IN INTEGER)
IS
SELECT all_invoices.customer_number
FROM all_invoices
WHERE all_invoices.year = p_year;
BEGIN
SELECT customer_number
BULK COLLECT INTO forbidden_customers_list
FROM forbidden_customers;
FOR rec_invoices in c_invoices(2022) loop
if forbidden_customers_list.exists(rec_invoices.customer_number) then
null;
end if;
end loop;
end;
/
I want to pass a table name and schema into a procedure, and have it generate insert, update and delete statements for the particular table. This is part of an automated testing solution (in a development environment) in which I need to test some change data capture. I want to make this dynamic as it is going to be need to be done for lots of different tables over a long period of time, and I need to call it via a REST request through ORDS, so don't want to have to make an endpoint for every table.
Update and delete are fairly easy, however I am struggling with the insert statement. Some of the tables being passed in have hundreds of columns with various constraints, fks etc. so I think it makes sense to just manipulate an existing record by changing only the primary key. I need to be able to modify the primary key to a new value known to me beforehand (e.g. '-1').
Ideally I would create a dynamic rowtype, and select into where rownum = 1, then loop round the primary keys found from all_constraints, and update the rowtype.pk with my new value, before inserting this into the table. Essentially the same as this but without knowing the table in advance.
e.g. rough idea
PROCEDURE manipulate_records(p_owner in varchar2, p_table in varchar2)
IS
cursor c_pk is
select column_name
from all_cons_columns
where owner = p_owner
and constraint_name in (select constraint_name
from all_constraints
where table_name = p_table
and constraint_type = 'P');
l_row tbl_passed_in%ROWTYPE --(I know this isn't possible but ideally)
BEGIN
-- dynamic sql or refcursor to collect a record
select * into tbl_passed_in from tablename where rownum = 1;
-- now loop through pks and reassign their values to my known value
for i in c_pk loop
...if matches then reassign;
...
end loop;
-- now insert the record into the table passed in
END manipulate_records;
I have searched around but haven't found any examples which fit this exact use case, where an unknown column needs to be modified and insert into a table.
Depending on how complex your procedure is, you might be able to store it as a template in a CLOB. Then pull it in, replace table and owner, then compile it.
DECLARE
prc_Template VARCHAR2(4000);
vc_Owner VARCHAR2(0008);
vc_Table VARCHAR2(0008);
BEGIN
vc_Table := 'DUAL';
vc_Owner := 'SYS';
-- Pull code into prc_Template from CLOB, but this demonstrates the concept
prc_Template := 'CREATE OR REPLACE PROCEDURE xyz AS r_Dual <Owner>.<Table>%ROWTYPE; BEGIN NULL; END;';
prc_Template := REPLACE(prc_Template,'<Owner>',vc_Owner);
prc_Template := REPLACE(prc_Template,'<Table>',vc_Table);
-- Create the procedure
EXECUTE IMMEDIATE prc_Template;
END;
Then you have the appropriate ROWTYPE available:
CREATE OR REPLACE PROCEDURE xyz AS r_Dual SYS.DUAL%ROWTYPE; BEGIN NULL; END;
But you can't create the procedure and run it in the same code block.
declare
vquery long;
cursor c1 is
select * from temp_name;
begin
for i in c1
loop
vquery :='INSERT INTO ot.temp_new(id)
select '''||i.id||''' from ot.customers';
dbms_output.put_line(i.id);
end loop;
end;
/
Output of select * from temp_name is :
ID
--------------------------------------------------------------------------------
customer_id
1 row selected.
I have customers table which has customer_id column.I want to insert all the customer_id into temp_new table but it is not being inserted. The PLSQL block executes successfully but the temp_new table is empty.
The output of dbms_output.put_line(i.id); is
customer_id
What is wrong there?
The main problem is that you generate a dynamic statement that you never execute; at some point you need to do:
execute immediate vquery;
But there are other problems. If you output the generated vquery string you'll see it contains:
INSERT INTO ot.temp_new(id)
select 'customer_id' from ot.customers
which means that for every row in customers you'll get one row in temp_new with ID set to the same fixed literal 'customer_id'. It's unlikely that's what you want; if customer_id is a column name from customers then it shouldn't be in single quotes.
As #mathguy suggested, long is not a sensible data type to use; you could use a CLOB but only really need a varchar2 here. So something more like this, where I've also switched to use an implicit cursor:
declare
l_stmt varchar2(4000);
begin
for i in (select id from temp_name)
loop
l_stmt := 'INSERT INTO temp_new(id) select '||i.id||' from customers';
dbms_output.put_line(i.id);
dbms_output.put_line(l_stmt);
execute immediate l_stmt;
end loop;
end;
/
db<>fiddle
The loop doesn't really make sense though; if your temp_name table had multiple rows with different column names, you'd try to insert the corresponding values from those columns in the customers table into multiple rows in temp_new, all in the same id column, as shown in this db<>fiddle.
I guess this is the starting point for something more complicated, but still seems a little odd.
I am working on an application and made the decision that all the queries would be procedures. I hope to have gains in performance and ease of maintenance by doing it this way. Our DBA's have also expressed interest in having it done this way.
I have an HR table where operations are performed on it each night, and any changes are recorded in a secondary table. We are not doing auditing, these change records are kept until the next run and show users the changes that have happened.
To keep my question shorter I have reduced the number of columns in HR.
The HR table ID, GROUP_NAME, and GROUP_LEVEL. The Drill table has ID and TYPEVALUE.
CREATE OR REPLACE PROCEDURE DOCSADM.DRILL_RECORD_POSITION (
RECORD_TYPE IN VARCHAR2,
OUT_ID OUT VARCHAR2,
OUT_GROUP_NAME OUT VARCHAR2,
OUT_GROUP_LEVEL OUT VARCHAR2
) AS
BEGIN
SELECT HR.ID, HR.GROUP_NAME, HR.GROUP_LEVEL
INTO OUT_ID, OUT_GROUP_NAME, OUT_GROUP_LEVEL
FROM HR_POSITION HR JOIN DRILL_POSITION DP ON (HR.ID = DP.ID) WHERE DP.TYPEVALUE = RECORD_TYPE;
END DRILL_RECORD_POSITION;
The procedure compiles without issue. Before doing all the work in the application to link to the procedure and extract the values which in this case will eventually be displayed in a view or webpage, I wanted to have a quick little script that would call the procedure and then display the results so I can verify in Oracle.
Loops
BEGIN
for t in (DRILL_RECORD_POSITION('D', V1,V5,V6))
loop
--dbms_output.put_line(t.V1 || t.V5 || t.V6);
dbms_output.put_line(t.OUT_ID);
end loop;
END;
/
CURSORS
DECLARE
V1 HR_POSITION.ID%TYPE;
V5 HR_POSITION.GROUP_NAME%TYPE;
V6 HR_POSITION.GROUP_LEVEL%TYPE;
CURSOR T_CUR IS DRILL_RECORD_POSITION('D', V1,V5,V6);
BEGIN
OPEN T_CUR;
DBMS_OUTPUT.PUTLINE('START');
LOOP
FETCH T_CUR INTO V1,V5,V6;
EXIT WHEN T_CUR%NOTFOUND;
DBMS_OUTPUT.PUTLINE(V1||V5||V6);
END LOOP;
CLOSE T_CUR;
END;
FOR LOOPS
DECLARE
V1 HR_POSITION.POSITION_ID%TYPE;
V5 HR_POSITION.GROUP_NAME%TYPE;
V6 HR_POSITION.GROUP_LEVEL%TYPE;
BEGIN
DBMS_OUTPUT.PUTLINE('START');
FOR INDEX IN (DRILL_RECORD_POSITION('D', V1,V5,V6))
LOOP
--DBMS_OUTPUT.PUTLINE(INDEX.ID);
DBMS_OUTPUT.PUTLINE(INDEX.V1||INDEX.V5||INDEX.V6);
END LOOP;
END;
Note: I edited the column names out and shorted some when transferring here so I might have made a few mistakes.
All the articles I have seen online show me how to display from within the original procedure or by using views, cursors, records. Unless I am wrong, Eclipse wont have any problems using the information in the current form which is why I am passing it that way. So I am not interested in changing the procedure and would like to work with it as is, since thats how the application will be doing it.
As this is the first of the stored procedures I am doing for the application, instead of using adhoc queries from the application, I dont have any existing examples to work from, which is why I believe the results will work fine, because it should be the same format the adhoc ones use.
Update:
In one of the comments, I was pointed to what should have been a solution. This was confirmed by another solution that was under it.
I keep getting the error
ORA-01422: exact fetch returns more than requested number of rows
So Im returning multiple rows, but that is my expectation and what is happening. I just cant seem to figure out how to display the results.
To test the procedure you showed, you would do something like:
declare
l_id hr_position.id%type;
l_group_name hr_position.group_name%type;
l_group_level hr_position.group_level%type;
begin
drill_record_position('D', l_id, l_group_name, l_group_level);
dbms_output.put_line(l_id ||':'|| l_group_name ||':'|| l_group_level);
end;
/
But that - or more specifically, your procedure - only works if there is exactly one row in the query's result set for the passed-in value type. It seems you're expecting multiple rows back (which would get too-many-rows), but there could also be non (which would get no-data-found).
So really it seems like your question should be about how to write your procedure so it works with one of the retrieval/test methods you tried.
If your procedure needs to return multiple rows then it can use a ref cursor, e.g.:
create or replace procedure drill_record_position (
p_record_type in varchar2,
p_ref_cursor out sys_refcursor
)
as
begin
open p_ref_cursor for
select hr.id, hr.group_name, hr.group_level
from hr_position hr
join drill_position dp
on hr.id = dp.id
where dp.typevalue = p_record_type;
end drill_record_position;
/
which you could then test with something like:
declare
l_ref_cursor sys_refcursor;
l_id hr_position.id%type;
l_group_name hr_position.group_name%type;
l_group_level hr_position.group_level%type;
begin
drill_record_position('D', l_ref_cursor);
loop
fetch l_ref_cursor into l_id, l_group_name, l_group_level;
exit when l_ref_cursor%notfound;
dbms_output.put_line(l_id ||':'|| l_group_name ||':'|| l_group_level);
end loop;
close l_ref_cursor;
end;
/
You can also do that as a function, which might be easier to work with from your application:
-- drop procedure drill_record_position;
create or replace function drill_record_position (p_record_type in varchar2)
return sys_refcursor as
l_ref_cursor sys_refcursor;
begin
open l_ref_cursor for
select hr.id, hr.group_name, hr.group_level
from hr_position hr
join drill_position dp
on hr.id = dp.id
where dp.typevalue = p_record_type;
return l_ref_cursor;
end drill_record_position;
/
declare
l_ref_cursor sys_refcursor;
l_id hr_position.id%type;
l_group_name hr_position.group_name%type;
l_group_level hr_position.group_level%type;
begin
l_ref_cursor := drill_record_position('D');
loop
fetch l_ref_cursor into l_id, l_group_name, l_group_level;
exit when l_ref_cursor%notfound;
dbms_output.put_line(l_id ||':'|| l_group_name ||':'|| l_group_level);
end loop;
close l_ref_cursor;
end;
/
You coudl also do this with collections and a pipelined function, which is more work to set up:
create type t_drill_obj as object (
-- use your real data types...
id number,
group_name varchar2(10),
group_level number
)
/
create type t_drill_tab as table of t_drill_obj
/
create or replace function drill_record_position (p_record_type in varchar2)
return t_drill_tab pipelined as
begin
for l_row in (
select t_drill_obj(hr.id, hr.group_name, hr.group_level) as obj
from hr_position hr
join drill_position dp
on hr.id = dp.id
where dp.typevalue = p_record_type
)
loop
pipe row (l_row.obj);
end loop;
return;
end drill_record_position;
/
but you could call it as part of another query, and even join tot he result if you needed to:
select * from table(drill_record_position('D'));
I am trying to simply insert some information to a table in Oracle using Forms. Sometimes the insert statement works, sometimes it doesn't. I'm just not experienced enough with Oracle to understand what's not working. Here's the code:
PROCEDURE create_account IS
temp_name varchar2(30);
temp_street varchar2(30);
temp_zip number(5);
temp_phone varchar2(30);
temp_login passuse.login%type;
temp_pass varchar2(30);
temp_total number(4);
temp_lgn passuse.lgn%type;
cursor num_cursor is
select MAX(ano)
from accounts;
cursor lgn_cursor is
select MAX(lgn)
from passuse;
BEGIN
temp_name:= Get_Item_Property('ACCOUNTS.A_NAME', database_value);
temp_street:= Get_Item_Property('ACCOUNTS.STREET', database_value);
temp_zip:= Get_Item_Property('ACCOUNTS.ZIP', database_value);
temp_phone:= Get_Item_Property('ACCOUNTS.STREET', database_value);
temp_login:= Get_Item_Property('PASSUSE.LOGIN', database_value);
temp_pass:= Get_Item_Property('PASSUSE.PASS', database_value);
open num_cursor;
fetch num_cursor into temp_total;
open lgn_cursor;
fetch lgn_cursor into temp_lgn;
if(lgn_cursor%found) then
if(num_cursor%found) then
temp_lgn := temp_lgn + 20;
--the trouble maker..
INSERT INTO passuse (lgn, a_type, login, pass)
VALUES (temp_lgn, 1, temp_login, temp_pass);
temp_total := temp_total+1;
INSERT INTO accounts(ano,lgn,a_name,street,zip,phone)
VALUES (temp_total,temp_lgn,temp_name,temp_street,temp_zip,temp_phone);
end if;
end if;
close lgn_cursor;
close num_cursor;
commit;
END;
To expand on #Mikpa's comment - it certainly appears that getting the values for ACCOUNTS.ANO and PASSUSE.LGN from sequences would be a good idea. Populating these fields automatically by using a trigger would also be helpful. Something like the following:
-- Note that the following is intended as a demo. When executing these statements
-- you'll probably have to modify them for your particular circumstances.
SELECT MAX(ANO) INTO nMax_ano FROM ACCOUNTS;
SELECT MAX(LGN) INTO nMax_lgn FROM PASSUSE;
CREATE SEQUENCE ACCOUNTS_SEQ START WITH nMax_ano+1;
CREATE SEQUENCE PASSUSE_SEQ START WITH nMax_lgn+1;
CREATE TRIGGER ACCOUNTS_BI
BEFORE INSERT ON ACCOUNTS
FOR EACH ROW
BEGIN
SELECT ACCOUNTS_SEQ.NEXTVAL
INTO :NEW.ANO
FROM DUAL;
END ACCOUNTS_BI;
CREATE TRIGGER PASSUSE_BI
BEFORE INSERT ON PASSUSE
FOR EACH ROW
BEGIN
SELECT PASSUSE_SEQ.NEXTVAL
INTO :NEW.LGN
FROM DUAL;
END PASSUSE_BI;
Having done the above you can now write your inserts into these tables as
INSERT INTO passuse (a_type, login, pass)
VALUES (1, temp_login, temp_pass)
RETURNING LGN INTO temp_lgn;
and
INSERT INTO accounts(lgn, a_name, street, zip, phone)
VALUES (temp_lgn, temp_name, temp_street, temp_zip, temp_phone);
Note that in the both statements the key values (PASSUSE.LGN and ACCOUNTS.ANO) are not mentioned in the field list as the new triggers should take care of filling them in correctly. Also note that when inserting into PASSUSE the RETURNING clause is used to get back the new value for LGN so it can be used in the insert into the ACCOUNTS table.
Share and enjoy.