Oracle save updated rows in log - sql

I have an update in my stored procedure. I would like to, save in my log the number of rows updated. How can I achieve this?

You can do something like this:
declare
l_rows_updated number;
begin
update table1 set col1 = 'abc' where foo = 'bar';
l_rows_updated := sql%rowcount;
insert into audit_table ( num_rows) values ( l_rows_updated );
end;

You can use the sql%rowcount which will return the number of rows Inserted or Updated by the last DML.
Depending upon how you are calling the procedure, the procedure can return the value as and OUT parameter and your calling program (could be Java, Python ) can write into a log file in the server.

Related

How to write a procedure to display the contents of a table in sql

I have a created a procedure as
create or replace procedure availability(num in number) as
begin
delete from vehicle_count;
insert into vehicle_count from select engine_no,count(engine_no)
from vehicle
where engine_no = num
group by engine_no;
end;
/
The procedure was created successfully but now i have to write a separate query to view the contents of vehicle_count as
select * from vehicle_count;
I tried inserting the select statement into the procedure after insertion but it showed a error stating "an INTO clause is expected in the select statement".
How can I create procedure to select the required contents and display it in a single execute statement?
Table schema
vehicle(vehicle_no,engine_no,offence_count,license_status,owner_id);
vehicle_count(engine_no,engine_count);
Check this (MS SQL SERVER)-
create or alter procedure availability(#num as int) as
begin
delete from vehicle_count;
insert into vehicle_count
output inserted.engine_no,inserted.count_engine_no
select engine_no,count(engine_no) as count_engine_no
from vehicle
where engine_no=#num
group by engine_no;
end;
If you want to use a SELECT into a PL/SQL block you should use either a SELECT INTO or a loop (if you want to print more rows).
You could use something like this:
BEGIN
SELECT engine_no, engine_count
INTO v_engine, v_count
FROM vehicle_count
WHERE engine_no = num;
EXCEPTION
WHEN NO_DATA_FOUND THEN
v_engine := NULL;
v_count := NULL;
END;
v_engine and v_count are two variables. You can declare them in your procedure, and they will contain the values you want to print.
You said that the procedure you wrote (actually, you posted here) compiled successfully. Well, sorry to inform you - that's not true. This is not a valid syntax:
insert into vehicle_count from select engine_no,count(engine_no)
----
from? Here?
Consider posting true information.
As of your question (if we suppose that that INSERT actually inserted something into a table):
at the beginning, you delete everything from the table
as SELECT counts number of rows that share the same ENGINE_NO (which is equal to the parameter NUM value), INSERT inserts none (if there's no such NUM value in the table) or maximum 1 row (because of aggregation)
therefore, if you want to display what's in the table, all you need is a single SELECT ... INTO statement whose result is displayed with a simple DBMS_OUTPUT.PUT_LINE which will be OK if you're doing it interactively (in SQL*Plus, SQL Developer, TOAD and smilar tools). Regarding table description, I'd say that ENGINE_NO should be a primary key (i.e. that not more than a single row with that ENGINE_NO value can exist in a table).
create or replace procedure availability (num in number) as
l_engine_no vehicle_count.engine_no%type;
l_engine_count vehicle_count.engine_count%type;
begin
delete from vehicle_count;
insert into vehicle_count (engine_no, engine_count)
select engine_no, count(engine_no)
from vehicle
where engine_no = num
group by engine_no;
-- This query shouldn't return TOO-MANY-ROWS if ENGINE_NO is a primary key.
-- However, it might return NO-DATA-FOUND if there's no such NUM there, so you should handle it
select engine_no, engine_count
into l_engine_no, l_engine_count
from vehicle_count
where engine_no = num;
dbms_output.put_line(l_engine_no ||': '|| l_engine_count);
exception
when no_data_found then
dbms_output.put_line('Nothing found for ENGINE_NO = ' || num);
end;
/
There are numerous alternatives to that (people who posted their answers/comments before this one mentioned some of those), and the final result you'd be satisfied with depends on where you want to display that information.

PostgreSQL variable in select and delete statements

The Problem: I have many delete lines in a PostgreSQL script where I am deleting data related to the same item in the database. Example:
delete from <table> where <column>=180;
delete from <anothertable> where <column>=180;
...
delete from <table> where <column>=180;
commit work;
There are about 15 delete statements deleting data that references <column>=180.
I have tried to replace the 180 with a variable so that I only have to change the variable, instead of all the lines in the code (like any good programmer would do). I can't seem to figure out how to do it, and it's not working.
NOTE: I am very much a SQL novice (I rarely use it), so I know there's probably a better way to do this, but please enlighten me on how I can fix this problem.
I have used these answers to try and fix it with no luck: first second third. I've even gone to the official PostgreSQL documentation, with no luck.
This is what I'm trying (these lines are just for testing and not in the actual script):
DO $$
DECLARE
variable INTEGER:
BEGIN
variable := 101;
SELECT * FROM <table> WHERE <column> = variable;
END $$;
I've also tried just delcaring it like this:
DECLARE variable INTEGER := 101;
Whenever I run the script after replacing one of the numbers with a variable this is the error I get:
SQL Error [42601]: ERROR: query has no destination for result data
Hint: If you want to discard the results of a SELECT, use PERFORM instead.
Where: PL/pgSQL function inline_code_block line 6 at SQL statement
Can someone tell me where I'm going wrong? It would be nice to only have to change the number in the variable, instead of in all the lines in the script, and I just can't seem to figure it out.
As #Vao Tsun said, you must define a destination to your SELECT statement. Use PERFORM otherwise:
--Test data
CREATE TEMP TABLE my_table (id, description) AS
VALUES (1, 'test 1'), (2, 'test 2'), (101, 'test 101');
--Example procedure
CREATE OR REPLACE FUNCTION my_procedure(my_arg my_table) RETURNS VOID AS $$
BEGIN
RAISE INFO 'Procedure: %,%', my_arg.id, my_arg.description;
END
$$ LANGUAGE plpgsql;
DO $$
DECLARE
variable INTEGER;
my_record my_table%rowtype;
BEGIN
variable := 101;
--Use your SELECT inside a LOOP to work with result
FOR my_record IN SELECT * FROM my_table WHERE id = variable LOOP
RAISE INFO 'Loop: %,%', my_record.id, my_record.description;
END LOOP;
--Use SELECT to populate a variable.
--In this case you MUST define a destination to your result data
SELECT * INTO STRICT my_record FROM my_table WHERE id = variable;
RAISE INFO 'Select: %,%', my_record.id, my_record.description;
--Use PERFORM instead of SELECT if you want to discard result data
--It's often used to call a procedure
PERFORM my_procedure(t) FROM my_table AS t WHERE id = variable;
END $$;
--DROP FUNCTION my_procedure(my_table);

Merge statement issue in oracle

I came from Microsoft SQL environment.I have two tables tak_ne and tak_beb and my requirement was to insert values from tak_beb to tak_ne if value is not present,if it is present just update.So i made a merge statement as shown below.But the problem now i am facing is veryday 50000 count is getting increment for sequence number.Oracle is stable database, and i don't know why they made it like that.So i create a Function and prevented incrementing sequence number.My question is ,is it a right approach by creating function.Following is what i did
merge into tak_ne a using tak_beb b ON (a.NAME=b.NAME)
When matched then
Update
Set a.AC_NO = b.AC_NO
a.LOCATION = b.LOCATION
a.MODEL = b.MODEL
When not matched then
insert
(
sl_no,
AC_NO,
LOCATION
MODEL
)
Values
(
s_slno_nextval
b.AC_NO
b.LOCATION
b.MODEL
)
and then i created a function
CREATE OR REPLACE FUNCTION s_slno_nextval
RETURN NUMBER
AS
v_nextval NUMBER;
BEGIN
SELECT s_emp.nextval
INTO v_nextval
FROM dual;
RETURN v_nextval;
END;
Oracle uses this approach to generate unique id for each row inserted by a statement. Your TAK_BEB table has probably 50000 rows, so the sequence is incremented 50000 times.
To hide increment into a function does not help. Function is called AND EXECUTED for every row, it increments sequence for 50000 times again. And it adds overhead with 50000 selects from dual table.
If you really need to use ONE value from sequence for ALL rows inserted by statement, use package variable:
create package single_id_pkg is
id Number;
function get_id return number;
end;
/
create or replace package body single_id_pkg is
function get_id return number is
begin
return id;
end;
end;
/
Now use for example before statement trigger on table to set the variable:
create trigger tak_ne_BSI_trg
before insert
on tak_ne
begin
select s_emp.nextval
into single_id_pkg.id
from dual;
end;
Insert trigger has one disadvantage - with MERGE clause it fires even if the statement does only updates rows (see https://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:25733900083512). If it is a problem, you have to initialize the variable in other way.
Next modify your statement to use a package variable:
merge into tak_ne a
using tak_beb b
on (a.NAME=b.NAME)
when matched then
update
set a.AC_NO = b.AC_NO
a.LOCATION = b.LOCATION
a.MODEL = b.MODEL
when not matched then
insert (sl_no,
AC_NO,
LOCATION,
MODEL)
values (single_id_pkg.get_id
b.AC_NO,
b.LOCATION,
b.MODEL)
In Oracle standard way to use autoincrement field is by using sequences. And of course it will increment sequence number each time you want to use it.
But you can omit calling sequence_name.nextval, hiding it in trigger it is considered the standard approach also.
CREATE OR REPLACE EDITIONABLE TRIGGER TAK_NE_ID_TR"
BEFORE INSERT ON tak_ne
FOR EACH ROW
BEGIN
IF :old.sl_no IS NULL THEN
:new.sl_no := s_emp.nextval;
END IF;
END;
If you want to add same id for a batch of your inserts you can use global temporary table for saving it. For example, like this:
create global temporary table tak_ne_id ("id" number) on commit delete rows
create or replace trigger tak_ne_BSI_trg
before insert
on tak_ne
begin
insert into tak_ne_id("id")
values(s_emp.nextval);
end
create or replace TRIGGER TAK_NE_ID_TR
BEFORE INSERT ON tak_ne
FOR EACH ROW
BEGIN
if :old.sl_no is null then
SELECT "id"
INTO :new.sl_no
FROM tak_ne_id;
end if;
END;
Then you can use you merge as before, and without calling nextval:
merge into tak_ne a using tak_beb b ON (a.NAME=b.NAME)
When matched then
update
set a.AC_NO = b.AC_NO,
a.LOCATION = b.LOCATION,
a.MODEL = b.MODEL
When not matched then
insert
(
AC_NO,
LOCATION,
MODEL
)
Values
(
b.AC_NO,
b.LOCATION,
b.MODEL
);

PL/SQL on Oracle 11g code is when executing stored procedure

What I am trying to do here is not run an insert code over and over, which is why I decided to create a stored procedure. Below is the script for the stored procedure and it created successfully, but when I execute the stored procedure "BEGIN SP_INSERT_PMC_UPDATE_DP; END;" I receive an error message "*wrong number or types of arguments in call to SP_INSERT_PMC_UPDATE_DP*"
My frame of thinking and sp code on this is:
1- I check to see if there are records in the PMC_UPDATE_DP and place that value into RECORD_COUNT.
2- Now if RECORD_COUNT is greater than zero I want to clear out all the records from the PMC_UPDATE_DP table.
3- If the RECORD_COUNT is equal to zero, then I want to insert data from the EXTERNAL_PMC_UPDATE_FD table to PMC_UPDATE_DP.
CREATE OR REPLACE PROCEDURE PMC.SP_INSERT_PMC_UPDATE_DP
(RECORD_COUNT OUT NUMBER) --Is my issue here???
IS
BEGIN
--Returns the total records and adds the value to RECORD_COUNT variable.
SELECT COUNT(*)
INTO RECORD_COUNT
FROM PMC.PMC_UPDATE_DP;
--Condition to see if RECORD_COUNT is greater than zero and dumps data to clear out PMC.PMC_UPDATE_DP table.
IF RECORD_COUNT > 0 THEN
EXECUTE IMMEDIATE 'TRUNCATE TABLE PMC.PMC_UPDATE_DP';
END IF;
--Condition to see if RECORD_COUNT equals zero. If true insert data into PMC_UPDATE_DP table from the PMC.EXTERNAL_PMC_UPDATE_FD table.
IF RECORD_COUNT = 0 THEN
INSERT INTO PMC.PMC_UPDATE_DP
( JOB_ID,
CONTROL_ID,
ACCT_NO,
CALC_DIVIDEND,
CERT_NEW_SHARES,
CALC_CASH_DISBURSMENT,
DECEASED,
STATUS,
ALPHA_SP1,
ALPHA_SP2,
ALPHA_SP3,
ALPHA_SP4,
NUM_SP1,
NUM_SP2,
NUM_SP3,
NUM_SP4,
DONT_CALL,
DONT_MAIL
)
SELECT JOB_ID,
CONTROL_ID,
ACCT_NO,
CALC_DIVIDEND,
CERT_NEW_SHARES,
CALC_CASH_DISBURSMENT,
DECEASED,
STATUS,
ALPHA_SP1,
ALPHA_SP2,
ALPHA_SP3,
ALPHA_SP4,
NUM_SP1,
NUM_SP2,
NUM_SP3,
NUM_SP4,
DONT_CALL,
DONT_MAIL
FROM PMC.EXTERNAL_PMC_UPDATE_FD
COMMIT;
END IF;
END;
If you want to call a procedure with an OUT parameter, you'd need to pass in a local variable so Oracle has something to hold the output.
DECLARE
l_record_count pls_integer;
BEGIN
PMC.SP_INSERT_PMC_UPDATE_DP ( l_record_count );
-- Do something with l_record_count, probably not just calling dbms_output
-- dbms_output.put_line( 'Record count = ' || l_record_count );
END;
If you are not planning on doing anything with the ouput, perhaps you really don't want the procedure to have an OUT parameter. Perhaps you just want to declare record_count as a local variable.

PLSQL Insert into with subquery and returning clause

I can't figure out the correct syntax for the following pseudo-sql:
INSERT INTO some_table
(column1,
column2)
SELECT col1_value,
col2_value
FROM other_table
WHERE ...
RETURNING id
INTO local_var;
I would like to insert something with the values of a subquery.
After inserting I need the new generated id.
Heres what oracle doc says:
Insert Statement
Returning Into
OK i think it is not possible only with the values clause...
Is there an alternative?
You cannot use the RETURNING BULK COLLECT from an INSERT.
This methodology can work with updates and deletes howeveer:
create table test2(aa number)
/
insert into test2(aa)
select level
from dual
connect by level<100
/
set serveroutput on
declare
TYPE t_Numbers IS TABLE OF test2.aa%TYPE
INDEX BY BINARY_INTEGER;
v_Numbers t_Numbers;
v_count number;
begin
update test2
set aa = aa+1
returning aa bulk collect into v_Numbers;
for v_count in 1..v_Numbers.count loop
dbms_output.put_line('v_Numbers := ' || v_Numbers(v_count));
end loop;
end;
You can get it to work with a few extra steps (doing a FORALL INSERT utilizing TREAT)
as described in this article:
returning with insert..select
T
to utilize the example they create and apply it to test2 test table
CREATE or replace TYPE ot AS OBJECT
( aa number);
/
CREATE TYPE ntt AS TABLE OF ot;
/
set serveroutput on
DECLARE
nt_passed_in ntt;
nt_to_return ntt;
FUNCTION pretend_parameter RETURN ntt IS
nt ntt;
BEGIN
SELECT ot(level) BULK COLLECT INTO nt
FROM dual
CONNECT BY level <= 5;
RETURN nt;
END pretend_parameter;
BEGIN
nt_passed_in := pretend_parameter();
FORALL i IN 1 .. nt_passed_in.COUNT
INSERT INTO test2(aa)
VALUES
( TREAT(nt_passed_in(i) AS ot).aa
)
RETURNING ot(aa)
BULK COLLECT INTO nt_to_return;
FOR i IN 1 .. nt_to_return.COUNT LOOP
DBMS_OUTPUT.PUT_LINE(
'Sequence value = [' || TO_CHAR(nt_to_return(i).aa) || ']'
);
END LOOP;
END;
/
Unfortunately that's not possible. RETURNING is only available for INSERT...VALUES statements. See this Oracle forum thread for a discussion of this subject.
You can't, BUT at least in Oracle 19c, you can specify a SELECT subquery inside the VALUES clause and so use RETURNING! This can be a good workaround, even if you may have to repeat the WHERE clause for every field:
INSERT INTO some_table
(column1,
column2)
VALUES((SELECT col1_value FROM other_table WHERE ...),
(SELECT col2_value FROM other_table WHERE ...))
RETURNING id
INTO local_var;
Because the insert is based on a select, Oracle is assuming that you are permitting a multiple-row insert with that syntax. In that case, look at the multiple row version of the returning clause document as it demonstrates that you need to use BULK COLLECT to retrieve the value from all inserted rows into a collection of results.
After all, if your insert query creates two rows - which returned value would it put into an single variable?
EDIT - Turns out this doesn't work as I had thought.... darn it!
This isn't as easy as you may think, and certainly not as easy as it is using MySQL. Oracle doesn't keep track of the last inserts, in a way that you can ping back the result.
You will need to work out some other way of doing this, you can do it using ROWID - but this has its pitfalls.
This link discussed the issue: http://forums.oracle.com/forums/thread.jspa?threadID=352627