Related
The UPSERT operation either updates or inserts a row in a table, depending if the table already has a row that matches the data:
if table t has a row exists that has key X:
update t set mystuff... where mykey=X
else
insert into t mystuff...
Since Oracle doesn't have a specific UPSERT statement, what's the best way to do this?
The MERGE statement merges data between two tables. Using DUAL
allows us to use this command. Note that this is not protected against concurrent access.
create or replace
procedure ups(xa number)
as
begin
merge into mergetest m using dual on (a = xa)
when not matched then insert (a,b) values (xa,1)
when matched then update set b = b+1;
end ups;
/
drop table mergetest;
create table mergetest(a number, b number);
call ups(10);
call ups(10);
call ups(20);
select * from mergetest;
A B
---------------------- ----------------------
10 2
20 1
The dual example above which is in PL/SQL was great becuase I wanted to do something similar, but I wanted it client side...so here is the SQL I used to send a similar statement direct from some C#
MERGE INTO Employee USING dual ON ( "id"=2097153 )
WHEN MATCHED THEN UPDATE SET "last"="smith" , "name"="john"
WHEN NOT MATCHED THEN INSERT ("id","last","name")
VALUES ( 2097153,"smith", "john" )
However from a C# perspective this provide to be slower than doing the update and seeing if the rows affected was 0 and doing the insert if it was.
An alternative to MERGE (the "old fashioned way"):
begin
insert into t (mykey, mystuff)
values ('X', 123);
exception
when dup_val_on_index then
update t
set mystuff = 123
where mykey = 'X';
end;
Another alternative without the exception check:
UPDATE tablename
SET val1 = in_val1,
val2 = in_val2
WHERE val3 = in_val3;
IF ( sql%rowcount = 0 )
THEN
INSERT INTO tablename
VALUES (in_val1, in_val2, in_val3);
END IF;
insert if not exists
update:
INSERT INTO mytable (id1, t1)
SELECT 11, 'x1' FROM DUAL
WHERE NOT EXISTS (SELECT id1 FROM mytble WHERE id1 = 11);
UPDATE mytable SET t1 = 'x1' WHERE id1 = 11;
None of the answers given so far is safe in the face of concurrent accesses, as pointed out in Tim Sylvester's comment, and will raise exceptions in case of races. To fix that, the insert/update combo must be wrapped in some kind of loop statement, so that in case of an exception the whole thing is retried.
As an example, here's how Grommit's code can be wrapped in a loop to make it safe when run concurrently:
PROCEDURE MyProc (
...
) IS
BEGIN
LOOP
BEGIN
MERGE INTO Employee USING dual ON ( "id"=2097153 )
WHEN MATCHED THEN UPDATE SET "last"="smith" , "name"="john"
WHEN NOT MATCHED THEN INSERT ("id","last","name")
VALUES ( 2097153,"smith", "john" );
EXIT; -- success? -> exit loop
EXCEPTION
WHEN NO_DATA_FOUND THEN -- the entry was concurrently deleted
NULL; -- exception? -> no op, i.e. continue looping
WHEN DUP_VAL_ON_INDEX THEN -- an entry was concurrently inserted
NULL; -- exception? -> no op, i.e. continue looping
END;
END LOOP;
END;
N.B. In transaction mode SERIALIZABLE, which I don't recommend btw, you might run into
ORA-08177: can't serialize access for this transaction exceptions instead.
I'd like Grommit answer, except it require dupe values. I found solution where it may appear once: http://forums.devshed.com/showpost.php?p=1182653&postcount=2
MERGE INTO KBS.NUFUS_MUHTARLIK B
USING (
SELECT '028-01' CILT, '25' SAYFA, '6' KUTUK, '46603404838' MERNIS_NO
FROM DUAL
) E
ON (B.MERNIS_NO = E.MERNIS_NO)
WHEN MATCHED THEN
UPDATE SET B.CILT = E.CILT, B.SAYFA = E.SAYFA, B.KUTUK = E.KUTUK
WHEN NOT MATCHED THEN
INSERT ( CILT, SAYFA, KUTUK, MERNIS_NO)
VALUES (E.CILT, E.SAYFA, E.KUTUK, E.MERNIS_NO);
I've been using the first code sample for years. Notice notfound rather than count.
UPDATE tablename SET val1 = in_val1, val2 = in_val2
WHERE val3 = in_val3;
IF ( sql%notfound ) THEN
INSERT INTO tablename
VALUES (in_val1, in_val2, in_val3);
END IF;
The code below is the possibly new and improved code
MERGE INTO tablename USING dual ON ( val3 = in_val3 )
WHEN MATCHED THEN UPDATE SET val1 = in_val1, val2 = in_val2
WHEN NOT MATCHED THEN INSERT
VALUES (in_val1, in_val2, in_val3)
In the first example the update does an index lookup. It has to, in order to update the right row. Oracle opens an implicit cursor, and we use it to wrap a corresponding insert so we know that the insert will only happen when the key does not exist. But the insert is an independent command and it has to do a second lookup. I don't know the inner workings of the merge command but since the command is a single unit, Oracle could execute the correct insert or update with a single index lookup.
I think merge is better when you do have some processing to be done that means taking data from some tables and updating a table, possibly inserting or deleting rows. But for the single row case, you may consider the first case since the syntax is more common.
A note regarding the two solutions that suggest:
1) Insert, if exception then update,
or
2) Update, if sql%rowcount = 0 then insert
The question of whether to insert or update first is also application dependent. Are you expecting more inserts or more updates? The one that is most likely to succeed should go first.
If you pick the wrong one you will get a bunch of unnecessary index reads. Not a huge deal but still something to consider.
Try this,
insert into b_building_property (
select
'AREA_IN_COMMON_USE_DOUBLE','Area in Common Use','DOUBLE', null, 9000, 9
from dual
)
minus
(
select * from b_building_property where id = 9
)
;
From http://www.praetoriate.com/oracle_tips_upserts.htm:
"In Oracle9i, an UPSERT can accomplish this task in a single statement:"
INSERT
FIRST WHEN
credit_limit >=100000
THEN INTO
rich_customers
VALUES(cust_id,cust_credit_limit)
INTO customers
ELSE
INTO customers SELECT * FROM new_customers;
Hi i have this simple trigger in oracle
CREATE OR REPLACE TRIGGER OCAP_CREATE_NCRB
BEFORE INSERT
ON OCAP_TBLOCAP
REFERENCING NEW AS NEW OLD AS OLD
FOR EACH ROW
DECLARE
Defect_Type varchar2(16);
out_ varchar2(60);
BEGIN
Select A.DEFECT_TYPE into Defect_Type from OCAP_TBLDEFECT A where A.DEFECT_ID = :NEW.DEFECT;
IF Defect_Type = 'C' THEN
--Create NCRB
SP_INSERTTBLD1D2(23,LPAD(:NEW.ISSUED_BY,6,'0'),0,'0','0','035823','Draft',' ',' ',34,' ',0,461,0,0,'035105',trunc(sysdate),' ','A',Lpad(:NEW.ISSUED_BY,6,'0'),Lpad(:NEW.ISSUED_BY,6,'0'),trunc(sysdate),'A',:New.BATCH_NO,out_);
--insert action
SP_INSERTTBLFORMYACTION(Lpad(:NEW.ISSUED_BY,6,'0'), out_, Lpad(:NEW.ISSUED_BY,6,'0'), Lpad(:NEW.ISSUED_BY,'0'), 'Draft');
--Insert other affected Lots
insert into TBLD2LOT(NCRBSERIESNO,LOTNO,CREATEDBY,CREATEDDT,SEQNO) Select (out_), A.BATCH_NO,Lpad(:NEW.ISSUED_BY,6,'0'),sysdate,(TBLD2LOTSEQ.nextval) from OCAP_OTHERBATCH A where A.OCAP_ID = :NEW.OCAP_NO;
--add NCRBSeries no. to table OCAP_TBLOCAP for referencing
Update OCAP_TBLOCAP set NCRBSERIESNO = out_ where OCAP_NO = :NEW.OCAP_NO;
--Insert ocap history
END IF;
END Ocap_Create_NCRB;
/
the first 2 stored procedure is working fine but the insert query is not .
I try to excute the insert query manunaly by replacing the Out_ and the :new.Ocap_no it is working fine.
Is there something wrong in my query?
Hope someone help me out with this.
If it isn't working, then
from OCAP_OTHERBATCH A
where A.OCAP_ID = :NEW.OCAP_NO; --> this condition is never met
which means that no rows in OCAP_OTHERBATCH contain OCAP_ID value which is equal to :NEW.OCAP_NO.
Might be because of wrong letter case, CHAR datatype (right-padded with spaces up to column's full length), ... who knows. Without tables' description and sample data, it is difficult to guess.
My statement:
SELECT ROW_ID DATA_T WHERE CITY_ID=2000 AND IS_FREE=0 AND ROWNUM = 1
is used to retrieve the first row for a db table that has many entries with CITY_ID equal to 2000.
The ROW_ID that is returned is then used in an UPDATE statement in order to use this row and set IS_FREE=1.
That worked very well until two threads called the SELECT statement and the got the same ROW_ID obviously... That is my problem in a few words.
I am using ORACLE DB (12.x)
How do I resolve the problem? Can I use FOR UPDATE in this case?
I want every "client" somehow to get a different row or at least lock on of them
Something like this
function get_row_id return number
as
cursor cur_upd is
SELECT ROW_ID FROM TB WHERE CITY_ID=2000 AND IS_FREE=0 AND ROWNUM = 1
FOR UPDATE SKIP LOCKED;
begin
for get_cur_upd in cur_upd
loop
update TB
set IS_FREE = 1
where ROW_ID = get_cur_upd.ROW_ID;
commit work;
return get_cur_upd.ROW_ID;
end loop;
return null;
end;
commit or not after update depends on your logic.
Also you can return row_id without update&commit and do it later outside func.
I am new to PLSQL and I am trying to execute this stored procedure shown here.
This stored procedure will check for a particular row and based on the count update the table or insert. But I am getting below errors as a whole.
31/18 PL/SQL: ORA-00928: missing SELECT keyword
31/1 PL/SQL: SQL Statement ignored
37/26 PL/SQL: ORA-00933: SQL command not properly ended
36/1 PL/SQL: SQL Statement ignored
I tried my best to solve them. Could you please help in solving the issue?
This is the procedure I have written for this task:
CREATE OR REPLACE PROCEDURE LPR_LP_TEST.SP_PTMS_NOTES
(
p_app_lse_s IN mjl.app_lse_s%TYPE,
p_dt_ent_s IN mjl.dt_ent_s%TYPE,
p_note_type_s IN mjl.note_type_s%TYPE,
p_prcs_c IN mjl.prcs_c%TYPE,
p_prio_c IN mjl.prio_c%TYPE,
p_note_title_s IN mjl.note_title_s%TYPE,
p_info1_s IN mjl.info1_s%TYPE,
p_info2_s IN mjl.info2_s%TYPE
)
AS
v_rowcount_i number;
v_lien_date mjl.info1_s%TYPE;
--v_lien_date NMAC_PTMS_NOTEBK_SG.LIEN_DT%TYPE;
v_asst_amount mjl.info2_s%TYPE;
BEGIN
app_lse_s:=trim(app_lse_s);
dbms_output.put_line(app_lse_s);
select LIEN_DT,ASES_PRT_1_AM
INTO v_lien_date,v_asst_amount
from NMAC_PTMS_NOTEBK_SG
where LSE_ID ='&2';
select count(*) into v_rowcount_i from MJL where trim(app_lse_s) ='&2';
if v_rowcount_i = 0 then
begin
Insert into MJL
('app_lse_s','dt_ent_s','note_type_s','prcs_c','prio_c','note_title_s','info
1_s','Info2_s')
values ('&2','sysdate','SPPT','Y','1','Property Tax
Assessment','v_lien_date','v_asst_amount');
end;
else
begin
update mjl
set dt_ent_s = 'sysdate' and note_type_s = 'SPPT' and prcs_c = 'Y' and
prio_c = '1' and note_title_s = 'Property Tax Assessment' and info1_s =
'v_lien_date' and Info2_s = 'v_asst_amount'
where trim(app_lse_s) = '&2';
end;
end if;
commit;
end;
/
I believe your procedure should look something like:
CREATE OR REPLACE PROCEDURE LPR_LP_TEST.SP_PTMS_NOTES
(
p_app_lse_s IN mjl.app_lse_s%TYPE,
p_dt_ent_s IN mjl.dt_ent_s%TYPE,
p_note_type_s IN mjl.note_type_s%TYPE,
p_prcs_c IN mjl.prcs_c%TYPE,
p_prio_c IN mjl.prio_c%TYPE,
p_note_title_s IN mjl.note_title_s%TYPE,
p_info1_s IN mjl.info1_s%TYPE,
p_info2_s IN mjl.info2_s%TYPE
)
AS
v_rowcount_i number;
v_lien_date mjl.info1_s%TYPE;
--v_lien_date NMAC_PTMS_NOTEBK_SG.LIEN_DT%TYPE;
v_asst_amount mjl.info2_s%TYPE;
v_app_lse_s mjl.app_lse_s%TYPE;
BEGIN
v_app_lse_s := trim(p_app_lse_s);
-- I hope this dbms_output line is for temporary debug purposes only
-- and will be removed in the production version!
dbms_output.put_line(app_lse_s);
merge into mjl tgt
using (select lse_s app_lse_s,
sysdate dt_ent_s,
'SPPT' note_type_s,
'Y' prcs_c,
'1' prio_c,
'Property Tax Assessment' note_title_s,
lien_dt info1_s,
ases_prt_1_am info2_s
from nmac_ptms_notebk_sg
where lse_id = v_app_lse_s) src
on (tgt.app_lse_s = src.app_lse_s)
when matched then
update set tgt.dt_ent_s = src.dt_ent_s,
tgt.note_title_s = src.note_title_s,
tgt.info1_s = src.info1_s,
tgt.info2_s = src.info2_s
where tgt.dt_end_s != src.dt_ent_s
or tgt.note_title_s != src.note_title_s
or tgt.info1_s != src.info1_s
or tgt.info2_s != src.info2_s
when not matched then
insert (tgt.app_lse_s,
tgt.dt_ent_s,
tgt.note_type_s,
tgt.prcs_c,
tgt.prio_c,
tgt.note_title_s,
tgt.info1_s,
tgt.info2_s)
values (src.app_lse_s,
src.dt_ent_s,
src.note_type_s,
src.prcs_c,
src.prio_c,
src.note_title_s,
src.info1_s,
src.info2_s);
commit;
end;
/
Things for you to note about your procedure and what I did to come up with the above procedure:
You have a tendency to enclose everything in single quotes. Single quotes are used to declare something as a string, i.e. some_variable := 'string value'. If you put single quotes around something that is actually an identifier, you are really telling Oracle to treat it as a string - which will result in all sorts of errors! The only time you should use quotes around an identifier is when the identifier's name is case sensitive, and you should use double-quotes. E.g. select * from "lower_case_tablename". (N.B. I say "should" here, but that's a guideline; you can use double-quotes around non-case-sensitive identifier names, but if you do so, the name should be in uppercase - i.e. select * from "DUAL";).
Your update statement syntax was incorrect - updates to several columns in a single statement are separated by commas, not ands.
The begins and ends around your insert and update statements are unnecessary.
If you're going to have an implicit cursor (i.e. the select ... into <variable list> from ... in the procedure body), you need to make sure you handle the NO_DATA_FOUND and TOO_MANY_ROWS exceptions that might be thrown up.
I set up a variable to store the trimmed value passed in by the parameter p_app_lse_s - I assume that this is what you meant to do? I also replaced all the calls to '&2' with the variable.
If you need to do an upsert (i.e. insert if the row doesn't already exist, otherwise update) then consider a MERGE statement. If you absolutely must keep them separate, then don't check for the existence of the row first; do the insert first and check for a DUP_VAL_ON_INDEX error - then do the update in the exception handler. Alternatively, do the update first and check SQL%ROWCOUNT to see if rows were amended and if not, then do the insert. A MERGE is preferable, though, since it means there's no opportunity for someone to insert a row in a different session in the split second it takes the database to go between the two statements.
By using a MERGE statement, I was able to incorporate all your logic into a single SQL statement, which makes your procedure simpler and easier to debug. For a start, I'm betting the other parameters in your procedure need to be used inside the procedure; it's easy to update the source query in the merge statement to replace the hardcoded values with the parameter names! I'll leave that as an exercise for you to do.
If you're getting the info1_s and info2_s values from the nmac_ptms_notebk_sg, do you really need the p_info1_s and p_info2_s parameters? They wouldn't seem to be needed, IMHO.
Finally, this procedure is doing the work a single app_lse_s at a time. If your database processing is OLTP, that's fine. If it's doing batch processing, and your code looks something like the following pseudo-code:
for each row in <this cursor>
loop
execute the lpr_lp_test.sp_ptms_notes procedure
end loop
then you'd be better off merging the sp_ptms_notes procedure into the calling procedure and doing the work in a single MERGE statement.
ETA: If you have a staging table (which could be an external table or a Global Temporary Table (GTT) or even a normal heap table) that contains the data you want to load into your database, then your merge statement would become something like:
merge into mjl tgt
using (select trim(st.app_lse_s) app_lse_s,
sysdate dt_ent_s,
'SPPT' note_type_s,
'Y' prcs_c,
'1' prio_c,
'Property Tax Assessment' note_title_s,
npns.lien_dt info1_s,
npns.ases_prt_1_am info2_s
from staging_table st
inner join nmac_ptms_notebk_sg npns-- maybe left outer join?
on trim(st.app_lse_s) = npns.lse_s) src
on (tgt.app_lse_s = src.app_lse_s)
when matched then
update set tgt.dt_ent_s = src.dt_ent_s,
tgt.note_title_s = src.note_title_s,
tgt.info1_s = src.info1_s,
tgt.info2_s = src.info2_s
where tgt.dt_end_s != src.dt_ent_s
or tgt.note_title_s != src.note_title_s
or tgt.info1_s != src.info1_s
or tgt.info2_s != src.info2_s
when not matched then
insert (tgt.app_lse_s,
tgt.dt_ent_s,
tgt.note_type_s,
tgt.prcs_c,
tgt.prio_c,
tgt.note_title_s,
tgt.info1_s,
tgt.info2_s)
values (src.app_lse_s,
src.dt_ent_s,
src.note_type_s,
src.prcs_c,
src.prio_c,
src.note_title_s,
src.info1_s,
src.info2_s);
You can see that I've joined the nmac_ptms_notebk_sg table to the staging table, and used that to generate the set of data that needs to be merged into your mjl table. If your file/staging table also contains information for the other columns (dt_ent_s, note_type_s, etc) then you can replace the hardcoded values with the columns from the staging table.
I have a couple of questions arounbd ref_cursors. Below is a ref_cursor that returns a a single row to a Unix calling script based on what is passed in and although the select looks a little untidy, it works as expected.
My first question is that in the select I join to a lookup table to retrieve a single lookup value 'trigram' and on testing found that this join will occasionally fail as no value exists. I have tried to capture this with no_data_found and when others exception but this does not appear to be working.
Ideally if the join fails I would still like to return the values to the ref_cursor but add something like 'No Trigram' into the trigram field - primarily I want to capture exception.
My second question is more general about ref_cursors - While initially I have created this in its own procedure, it is likely to get called by the main processing procedure a number of times, one of the conditions requires a seperate select but the procedure would only ever return one ref_cur when called, can the procdure ref_cur out be associated with 2 queries.
CREATE OR REPLACE PROCEDURE OPC_OP.SiteZone_status
(in_site_id IN AW_ACTIVE_ALARMS.site_id%TYPE
,in_zone_id IN AW_ACTIVE_ALARMS.zone_id%TYPE
,in_mod IN AW_ACTIVE_ALARMS.module%TYPE
,p_ResultSet OUT TYPES.cursorType
)
AS
BEGIN
OPEN p_ResultSet FOR
SELECT a.site_id,'~',a.zone_id,'~',b.trigram,'~',a.module,'~',a.message_txt,'~',a.time_stamp
FROM AW_ACTIVE_ALARMS a, AW_TRIGRAM_LOCATION b
WHERE a.site_id = b.site_id
AND a.zone_id = b.zone_id
AND a.site_id = in_site_id
AND a.zone_id = in_zone_id
AND a.module LIKE substr(in_mod,1,3)||'%'
AND weight = (select max(weight) from AW_ACTIVE_ALARMS c
WHERE c.site_id = in_site_id
AND c.zone_id = in_zone_id
AND c.module LIKE substr(in_mod,1,3)||'%');
EXCEPTION
WHEN OTHERS
THEN
DBMS_OUTPUT.PUT_LINE('No Data Found');
END SiteZone_status;
I have modified my code to adopt answers provided and this now works as expected as a standalone procedure within my package, which when called via a UNIX script using:
v_process_alarm=$(sqlplus -s user/pass <
set colsep ','
set linesize 500
set pages 0 feedback off;
set serveroutput on;
VARIABLE resultSet REFCURSOR
EXEC alarm_pkg.rtn_active_alarm($site,$zone,$module, :resultSet);
PRINT :resultSet
EOF
)
However the procedure returning the ref cursor is to be called from the main processing procedure as I only want to return values if certain criteria are met. I have add an out refcurosr to my main procedure and set a variable to match, I then call my ref cursor procedure from here but this fails to compile
with the message 'Wrong number or types of argument in call'
My question is what is the correct way to call a procedure that has out refcursor from within a procedure and then return these values from there back to the calling script.
Oracle doesn't know whether a query will return rows until you fetch from the cursor. And it is not an error for a query to return 0 rows. So you will never get a no_data_found exception from opening a cursor. You'll only get that if you do something like a select into a local variable in which case a query that returns either 0 or more than 1 row is an error.
It sounds like you want to do an outer join to the AW_TRIGRAM_LOCATION table rather than a current inner join. This will return data from the other tables even if there is no matching row in aw_trigram_location. That would look something like this (I have no idea why every other column is a hard-coded tilde character, that seems exceptionally odd)
SELECT a.site_id,'~',
a.zone_id,'~',
nvl(b.trigram, 'No Trigram Found'),'~',
a.module,'~',
a.message_txt,'~',
a.time_stamp
FROM AW_ACTIVE_ALARMS a
LEFT OUTER JOIN AW_TRIGRAM_LOCATION b
ON( a.site_id = b.site_id AND
a.zone_id = b.zone_id )
WHERE a.site_id = in_site_id
AND a.zone_id = in_zone_id
AND a.module LIKE substr(in_mod,1,3)||'%'
AND weight = (select max(weight)
from AW_ACTIVE_ALARMS c
WHERE c.site_id = in_site_id
AND c.zone_id = in_zone_id
AND c.module LIKE substr(in_mod,1,3)||'%');
I'm not quite sure that I understand your last question. You can certainly put logic in your procedure to run a different query depending on an input parameter. Something like
IF( <<some condition>> )
THEN
OPEN p_ResultSet FOR <<query 1>>
ELSE
OPEN p_ResultSet FOR <<query 2>>
END IF;
Whether it makes sense to do this rather than adding additional predicates or creating separate procedures is a question you'd have to answer.
You can use a left outer join to your look-up table, which is clearer if you use ANSI join syntax rather than Oracle's old syntax. If there is no record in AW_TRIGRAM_LOCATION then b.trigram will be null, and you can then use NVL to assign a dummy value:
OPEN p_ResultSet FOR
SELECT a.site_id,'~',a.zone_id,'~',NVL(b.trigram, 'No Trigram'),'~',
a.module,'~',a.message_txt,'~',a.time_stamp
FROM AW_ACTIVE_ALARMS a
LEFT JOIN AW_TRIGRAM_LOCATION b
ON b.site_id = a.site_id
AND b.zone_id = a.zone_id
WHERE a.zone_id = in_zone_id
AND a.module LIKE substr(in_mod,1,3)||'%'
AND weight = (select max(weight) from AW_ACTIVE_ALARMS c
WHERE c.site_id = in_site_id
AND c.zone_id = in_zone_id
AND c.module LIKE substr(in_mod,1,3)||'%');
You won't get NO_DATA_FOUND opening a cursor, only when you fetch from it (depending on what is actually consuming this). It's a bad idea to catch WHEN OTHERS anyway - you would want to catch WHEN NO_DATA_FOUND, though it wouldn't help here. And using dbms_output to report an error relies on the client enabling its display, which you can't generally assume.