Update of several rows of the same table using trigger

Similar Questions

• Compare two rows in the same table

  Hi all
  
  I need to compare two rows in the same table, I don't know hoe to do it in pl/sql. Please help me on this.
  
  example:
  
  price of ro TR
  xya0001 AMA.7 12
  xya0003 ama6 14
  xya0004 AMA.7 16
  
  in table b is a unique value for each line, I need to compare the price column and see if the first value is less than or greater than the following value and, if there is more to put the corresponding value of br to a variable, and if it is less, put the corresponding value of the br to another variable. I don't know a method to do this, as I'm new to pl/sql. Please help me in this

  for data in(select tr,br,price, lag(price) over ( order by tr) newcol
  from yourtable)
  loop
  if nvl(data.newcol,0) > data.price then
  variable1:=data.br;
  else
  varable2:=data.br;
  end if;
  end loop;
  

• Update lines with the info from the other rows in the same Table.

  I'm trying to update the lines with the information of the same table. The table is loaded with information from a report that runs and there must be a new entry every month, but I would like to bring some of the info from the last month. This statement below works but updates all rows in the new load table and in my test case, I only did a few game only like 5 files need to get updates. It is an example of what I'm trying to do. If I add this (C2. COL_INVC_ID = C1. COL_INVC_ID) until the last "* where *" statement get an invalid identifier for 'C2 '. COL_INVC_ID ". So what I'm doing wrong here? How can I update only the lines where also in recent months run?
  
  Thanks in advance for any help!
  
  ------------
  Update OpenIssues OI1
  Together (OI1. NUM, OI1. Status, OI1. Code, OI1. LastModifiedDate) =
  (Select ios2. NUM, ios2. Status, ios2. Code, ios2. LastModifiedDate
  Of OpenIssues ios2
  Where OI2.num = OI1.num and ios2. TableLoadDate = TO_DATE (January 31, 2012 00:00:00 ',' ' the HH24: MI: SS DD/MM/YYYY)
  )
  Where and OI1. TableLoadDate = TO_DATE (February 29, 2012 00:00:00 ',' ' the HH24: MI: SS DD/MM/YYYY)
  ------------
  
  
  SQLMe

  As Frank suggested merger is much effective here, go...

    create table  temp
  as(
  select 1 eno, 1 amt , sysdate load_date from dual union all
  select 1 eno, 2 amt , add_months(sysdate,1) load_date from dual union all
  select 2 eno, 1 amt , sysdate load_date from dual union all
  select 2 eno, 2 amt , add_months(sysdate,1) load_date from dual
  );
  
  merge into temp t
  using (select eno, amt, load_date
           from temp
          where trunc(Load_Date) = TO_DATE('05/30/2012', 'MM/DD/YYYY')) s
  on ((s.eno = t.eno) and trunc(t.Load_Date) = TO_DATE('06/30/2012', 'MM/DD/YYYY'))
  when matched then
    update set t.amt = s.amt;
  commit;
  
  select * from temp;
  

• Possible to insert more than once in the same table using multi table insert?

  I used multi-table insert before insert a source separate from the tables without problem.
  
  However, when I want to insert into the same table two or more distinct lines, I encountered a problem because when I call nextval on the sequence since this is the same sequence # will try to use the same number for two inserts, which will raise a violation of PK constraint on the 2nd insert.
  
  A way around this problem?

  Another option is to create the sequence with increases of 2 or however many tables, you are targeting.
  When you then specify the. NEXTVAL, you must subtract the relative number of it, apart from the first table that you insert in to.

  Something like that;

  drop table t1;
  
  create table t1 (a number, b number);
  
  drop table t2;
  
  create table t2 (a number, b number);
  
  drop sequence test_seq
  /
  
  create sequence test_seq increment by 2 minvalue 0
  /
  
  insert all
  when 1 = 1 then
    into t1 (a, b) values (test_seq.nextval, 1)
  when 1 = 1 then
    into t2 (a, b) values (test_seq.nextval  - 1, 1)
  select 1, 1 from dual
  /
  

• Need a script to select the update the row to another row in the same table

  I have a table with the columns and values
  

  KeyID       EffectiveDate     InactiveDate
  1              01/01/2013
  1              01/02/2013
  1              01/03/2013
  2              12/31/2012
  2              01/02/2013
  2              01/03/2013

  I need to update the InactiveDate of a line with the EffectiveDate of a line with the EffectiveDate newer than the update line and the even KeyID.

  KeyID       EffectiveDate     InactiveDate
  1              01/01/2013      01/02/2013
  1              01/02/2013      01/03/2013
  1              01/03/2013
  2              12/31/2012      01/02/2013
  2              01/02/2013      01/03/2013
  2              01/03/2013

  I want to have a select script that shows

  KeyID       EffectiveDate        InactiveDate    New_InactiveDate
  1              01/01/2013                              01/02/2013
  1              01/02/2013                              01/03/2013
  1              01/03/2013
  2              12/31/2012                              01/02/2013
  2              01/02/2013                              01/03/2013
  2              01/03/2013

  Thanks for any help.
  
  Published by: 881656 on January 3, 2013 17:57
  
  Published by: 881656 on January 3, 2013 18:15
  
  Published by: 881656 on January 3, 2013 18:20

  Hello

  881656 wrote:
  I have a table with the columns and values

  KeyID       EffectiveDate     InactiveDate
  1              01/01/2013
  1              01/02/2013
  1              01/03/2013
  2              12/31/2012
  2              01/02/2013
  2              01/03/2013
  
  I need to update the InactiveDate of a row with the EffectiveDate of a row with the newer EffectiveDate than the row to be updated and with the same KeyID.
  
  KeyID       EffectiveDate     InactiveDate
  1              01/01/2013      01/02/2013
  1              01/02/2013      01/03/2013
  1              01/03/2013
  2              12/31/2012      01/02/2013
  2              01/02/2013      01/03/2013
  2              01/03/2013
  

  This sounds like a job for the analytical function of LEAD:

  MERGE INTO table_x     dst
  USING (
       SELECT  keyid
       ,     effectivedate
       ,     LEAD (effectivedate) OVER ( PARTITION BY  keyid
                                         ORDER BY         activedate
                                       )            AS inactivedate
        )               src
  WHEN MATCHED THEN UPDATE
  ON    (    src.id          = dst.id
        AND  src.effectivedate     = dst.effectivedate
        )
  SET     dst.inactivedate     = src.inactivedate
  ;
  

  I want to have a select script which shows
  
  KeyID       EffectiveDate        InactiveDate    New_InactiveDate
  1              01/01/2013                              01/02/2013
  1              01/02/2013                              01/03/2013
  1              01/03/2013
  2              12/31/2012                              01/02/2013
  2              01/02/2013                              01/03/2013
  2              01/03/2013
  

  Once that you have done the above MERGER, it is simply:

  SELECT    *
  FROM      table_x
  ORDER BY  keyid
  ,         effectivedate
  ;
  

  If you do not have sthe FUSION, then see the query in the USING clause of the MERGER.

  I hope that answers your question.
  If not, post a small example data (CREATE TABLE and only relevant columns, INSERT statements), and the results you want from this data.
  In the case of a DML (UPDATE), for example, the sample data should show what looks like the tables before the DML, and the results will be the content of the table changed after the DML.
  Explain, using specific examples, how you get these results from these data.
  Always say what version of Oracle you are using (for example, 11.2.0.2.0).
  See the FAQ forum {message identifier: = 9360002}

• Copy the data rows in the same table

  Here is the structure of the table, I work I would like all the value with ID = 1 in new lines. The ID must be 2 with the same data.

  I am using following query to accomplish, but get the error.

  Insert into hsp_column_detail_item (DETAIL_ID, VALUE, POSITION, GENERATION, OPERATOR, LABEL)

  Select 2, POSITION, GENERATION, OPERATOR, VALUE, LABEL

  Of

  hsp_column_detail_item

  where

  detail_id = 1

  ORA-02291: integrity constraint (PLANSAMP. FK_HSP_DETAIL_ID) violated - key parent not found

  Columns

  Detail_ID		1	THERE	INTEGER NUMBER	Frequency
  VALUE	2	THERE	FLOAT	None
  POSITION	3	THERE	INTEGER NUMBER	None
  GENERATION	4	THERE	INTEGER NUMBER	None
  OPERATOR	5	THERE	INTEGER NUMBER	None
  LABEL	6	THERE	VARCHAR2 (1500 bytes)	None

  Sample data:

  Label Detail_ID value generation operator Position

  1

  500

  0

  0

  1

  ABC

  1

  300

  1

  0

  1

  def

  1

  200

  2

  0

  1

  EFG

  Index

  Name of the index

  Column name

  Col_Detail_Item

  Detail_ID

  Col_Detail_Item

  Position

  866532 wrote:

  Where detail_id in

  (select detail_id in the hsp_column_detail where)

  dim1 = (select object_id from hsp_object where the object_name = 'Real' and object_type = 31) and

  Dim5 = (select object_id from hsp_object where the object_name = 'Work' and object_type = 35) and

  dim7 = (select object_id from hsp_object where the object_name = 'FY13' and object_type = 38)

  );

  ORA-00001: unique constraint (PLANSAMP. Voilated PK_HSP_COL_DETAIL)

  To not violate the unique constraint, two requirements:

  -The detail_id 5 you insert would not already exist in the table

  -Since you are forcing this detail_id, your subquery must return only one row: so you can write ' detail where id = (select...) "and:

  -either the dim1 / dim5 / dim7 filters are quite selective

  - or to make any decision on which detail_id to reproduce: max (detail_id) or min (detail_id) or any other way yo select the right / arbitrary

• Compare several records in the same table

  Hello, I m writing a bat file so I can export information that I question.
  
  I have an automatic integration which checks from time to time if there is no new client´s and generates a trigger.
  If an error levonorgestrol I the process is repeated until the client is located in the database.
  I can't create tables or change the structure.
  
  
  My problem is that I need to compare the record more updated with the CLIENT_ID field
  Let me give you an example:
  
  
  Table A
  
  ERROR_MESSAGE CREATEDUSERID CLIENT_ID
  0 success 01/01/2009
  1 error 01/01/2009
  2 success 01/01/2009
  1 success 01/02/2009
  3 success 01/02/2009
  4 error 01/02/2009
  
  I need to compare "1" client created on 01/01/2009 this error gived with new records to see if there's success and my
  query should only return the client_ID '4' and export with sqlplus
  
  Could you please help me?

  Hello

  It works very well with my data.
  What data do you use? After a few lines of sample data (CREATE TABLE AS executable... or INSERT... statements are best) that give you wrong results.

  Make sure that everything is spelled correctly.
  For example, roughly halfway through the query, you say

  and io.status = 'Erro' 
  

  and at the end you say

  having max(decode(io.status, 'Error', 1, 2))  ...
  

  That is the same ("Error" or "Error") in both places?

• Windows Update offers several times that the same installed upgrading

  original title: update Windows using Vista

  Windows Update keeps saying I need to install the same update: a security update for Microsoft Visual C++ 2005 Service Pack 1 Redistributable Package (KB2538242) I installed it successfully, but he continues to return again and again to the top.  Any ideas?  Thank you

  Launch a collateral request for assistance free Windows Update:

  https://support.Microsoft.com/OAS/default.aspx?Gprid=6527&St=1&wfxredirect=1&SD=GN>

  Visit the Microsoft Solution Center and antivirus security for resources and tools to keep your PC safe and healthy. If you have problems with the installation of the update itself, visit the Microsoft Update Support for resources and tools to keep your PC updated with the latest updates.

  If you /clear/ State only one specific updated because of problems and don't ask questions, you /he/ receive assistance free of charge for the question.

  North American customers can also obtain instant access to unlimited free support by email or unlimited individual chat by visiting the following Microsoft Web site:

  >

  For enterprise customers, support for security updates is available through your usual support contacts.

  How to hide an update in Windows Vista

  1 open Windows Update by clicking on the "Start" icon and then clicking on '' programs. '' Choose "Windows Update" in the list of programs.

  2 click on "View available updates" to move to the screen that allows you to select the updates available for your computer.

  3. Select an update of the list that you want to hide. Right-click on it to bring up a menu, then click on "Hide update". If user account control is enabled, a confirmation dialog box appears on the screen informing you that "Windows needs your permission to continue."

  4. click on 'Continue' to confirm your action. If there are additional updates that you want to hide, steps 4 and 5 for each of them.

  5 search for updates and then click on "View available updates" to ensure that the updates have been correctly hidden

  UTC/GMT is 03:38 Sunday, October 16, 2011

• With one of several rows with the same value for the same ID

  Hello

  I have this request:

  SELECT

  Count (case when EXISTS ())

  SELECT *.

  FROM business_log bl, su topic

  WHERE su.ID_SUBJECT = s.ID_SUBJECT

  and bl.id_subject = su.id_subject

  AND bl.value = 'resolved '.

  )

  then 1 end another null) num_solved

  OF THE subject

  It is possible that a subject is more than once 'resolved' in the table BUSINESS_LOG

  I want to count only one line solved for a topic.

  I need to use only under RESERVE the table in the main query due to other counts.

  Thank you very much.

  Concerning

  Milos

  Post edited by: 2796614

  in the examples before we talked abount 'Resolved' instead of 'resolved' as in your last example... to let you know, how it is stored.

  I had advice is not to use SEPARATE.

  So what... the evidence that any other question is faster than anything goes business_log, filter lines and can count distinct keys...

  separate within a group function is not the same thing as do select distinct...

  HTH

• COMPARING TWO ROWS IN THE SAME TABLE AND DELETE THEM USING DELETION BLOCK

  Hi all
  I have a problem. I have an Employee table
  
  employee
  
  Emp_name Emp_id Emp_status Emp_date
  
  John 1 P 11-27-2010
  
  Mike 2 26/11/2010 S
  
  Simon P 3 22 / 11 / 2010
  
  Dennis C 4 25/11/2010...
  
  
  I compare the rows in the table and their employee_status if 'P', should I remove the... Here, I should delete lines 1 and 3 as their Emp_status is 'P '. I only use BULK DELETE... I tried to use the join query internal and deletion, but it does not work... Can someone help me...

  Ooops, it should be:

  and e2.emp_status in ('P', 'C')

  not

  and e2.emp_status in ('P', 'A')

  Here it goes:

  SQL> select  *
    2    from  employees
    3  /
  
  E EMP_NAME      EMP_KEY          X
  - ---------- ---------- ----------
  C John              123          1
  P Mike              123          2
  P Paul              123          6
  C Harry             124          5
  A Gass              125          7
  C Gass              125          7
  
  6 rows selected.
  
  delete  employees e1
    where 2 = (
               select  count(distinct e2.emp_status)
                    from  employees e2
                    where e2.emp_key = e1.emp_key
                      and e2.emp_status in ('P','C')
                 )
  /
  
  3 rows deleted.
  
  SQL>
  

  SY.

• Insert several rows in the data table table

  Hi all
  
  I have a requirement as to insert multiple rows in the table for this table data only (I need to replicate the data).
  In this table, the primary key is a composite primary key with all the keys.primary foreign key and the foreign key to the Date. I need to change that date to the insertion.
  
  
  INSERT
  IN myschema. Fact_page_performance
  (
  time_sk,
  Batch_ID,
  delta_msec,
  delta_user_msec,
  error_code_sk,
  content_errs,
  element_count,
  page_bytes,
  Available,.
  date_sk
  
  )
  VALUES
  (SELECT time_sk,
  Batch_ID,
  delta_msec,
  delta_user_msec,
  error_code_sk,
  content_errs,
  element_count,
  page_bytes,
  Available
  OF myschema. FACT_PAGE_PERFORMANCE_BACKUP
  WHERE date_sk = 20090509, 20090510
  );
  
  But it gives error like missing expression.
  Could someone please help me.
  
  Thanks and greetings
  Swetha.

  You can have either the VALUES or not SELECT the two

  INSERT
  INTO myschema.Fact_page_performance
  (
  time_sk ,
  batch_id ,
  delta_msec ,
  delta_user_msec,
  error_code_sk ,
  content_errs ,
  element_count ,
  page_bytes ,
  Available ,
  date_sk
  
  )
  SELECT time_sk ,
  batch_id ,
  delta_msec ,
  delta_user_msec,
  error_code_sk ,
  content_errs ,
  element_count ,
  page_bytes ,
  Available
  FROM myschema.FACT_PAGE_PERFORMANCE_BACKUP
  WHERE date_sk=20090509,20090510;
  

• How to update columns with the value of other lines in the same table

  Hello
  
  I use Oracle 11.2, I'd use SQL statements to update a column based on values in other rows in the same table. Here are the details:
  
  create table TB_test (number 4 myId, crtTs date, date of MDPU);
  
  insert into tb_test (1, to_date ('20110101', 'YYYYMMDD'), null);
  insert into tb_test (1, to_date ('20110201', 'YYYYMMDD'), null);
  insert into tb_test (1, to_date ('20110301', 'YYYYMMDD'), null);
  insert into tb_test (2, to_date ('20110901', 'YYYYMMDD'), null);
  insert into tb_test (2, to_date ('20110902', 'YYYYMMDD'), null);
  
  After you run the SQL code, I would like to have the following result:
  
  1, 20110101, 20110201
  1, 20110201, 20110301
  1, 20110301, null
  2, 20110901, 20110902
  2, 20110902, null
  
  Thanks for your suggestion.

  I guess you need this, otherwise please explain logic correctly:

  SQL> merge into tb_test t
    2  using (
    3    select rowid as rid
    4         , lead(crtts) over(partition by myid order by crtts) as updts
    5    from tb_test
    6  ) v
    7  on (t.rowid = v.rid)
    8  when matched then update
    9   set t.updts = v.updts
   10  ;
  
  5 rows merged.
  
  SQL> select * from tb_test order by 1,2;
  
        MYID CRTTS     UPDTS
  ---------- --------- ---------
           1 01-JAN-11 01-FEB-11
           1 01-FEB-11 01-MAR-11
           1 01-MAR-11
           2 01-SEP-11 02-SEP-11
           2 02-SEP-11
  

• Several updates on the same Table

  Hello
  
  I need to update the same Table (T1) but to filter for different conditions as below.
  and I have a set of filter conditions 50 and update the same table.
  
  Is it possible to get in the single update statement?
  
  BEGIN
  UPDATE T1
  SET PTA_CLM_CNT = v_PTA_CLM_CNT__77,
  PTB_CLM_CNT = v_PTB_CLM_CNT__77
  WHERE run_dt = v_in_parm_dt
  AND state_code = '77';
  EXCEPTION
  WHEN NO_DATA_FOUND THEN
  null;
  WHILE OTHERS THEN
  v_error_cd: = SQLCODE;
  v_error_msg: = SUBSTR (SQLERRM, 1, 200);
  v_curr_record: = 'sum_bene_state_updt_77 ' | v_in_parm_dt;
  create_error_log ('_sum_cnts', v_error_cd, v_error_msg, v_curr_record);
  END;
  
  BEGIN
  UPDATE T1
  SET PTA_CLM_CNT_ = v_PTA_CLM_CNT__78,
  PTB_CLM_CNT_ = v_PTB_CLM_CNT__78
  WHERE run_dt = v_in_parm_dt
  AND state_code = '78';
  EXCEPTION
  WHEN NO_DATA_FOUND THEN
  null;
  WHILE OTHERS THEN
  v_error_cd: = SQLCODE;
  v_error_msg: = SUBSTR (SQLERRM, 1, 200);
  v_curr_record: = 'sum_bene_state_updt_78 ' | v_in_parm_dt;
  create_error_log ('sum_cnts', v_error_cd, v_error_msg, v_curr_record);
  END;
  
  Thanks in advance

  May be trying to use DECODE

  UPDATE T1
     SET PTA_CLM_CNT = DECODE(state_code,77,v_PTA_CLM_CNT_77,78,v_PTA_CLM_CNT_78)
         PTB_CLM_CNT = DECODE(state_code,77,v_PTB_CLM_CNT_77,78,v_PTB_CLM_CNT_78)
   WHERE run_dt = v_in_parm_dt;
  

• update to column values (false) in a copy of the same table with the correct values

  Database is 10gr 2 - had a situation last night where someone changed inadvertently values of column on a couple of hundred thousand records with an incorrect value first thing in the morning and never let me know later in the day. My undo retention was not large enough to create a copy of the table as it was 7 hours comes back with a "insert in table_2 select * from table_1 to timestamp...» "query, so I restored the backup previous nights to another machine and it picked up at 07:00 (just before the hour, he made the change), created a dblink since the production database and created a copy of the table of the restored database.
  
  My first thought was to simply update the table of production with the correct values of the correct copy, using something like this:
  
  
  Update mnt.workorders
  Set approvalstat = (select b.approvalstat
  mnt.workorders a, mnt.workorders_copy b
  where a.workordersoi = b.workordersoi)
  where exists (select *)
  mnt.workorders a, mnt.workorders_copy b
  where a.workordersoi = b.workordersoi)
  
  It wasn't the exact syntax, but you get the idea, I wanted to put the incorrect values in x columns in the tables of production with the correct values of the copy of the table of the restored backup. Anyway, it was (or seem to) works, but I look at the process through OEM it was estimated 100 + hours with full table scans, so I killed him. I found myself just inserting (copy) the lines added to the production since the table copy by doing a select statement of the production table where < col_with_datestamp > is > = 07:00, truncate the table of production, then re insert the rows from now to correct the copy.
  
  Do a post-mortem today, I replay the scenario on the copy that I restored, trying to figure out a cleaner, a quicker way to do it, if the need arise again. I went and randomly changed some values in a column number (called "comappstat") in a copy of the table of production, and then thought that I would try the following resets the values of the correct table:
  
  Update (select a.comappstat, b.comappstat
  mnt.workorders a, mnt.workorders_copy b
  where a.workordersoi = b.workordersoi - this is a PK column
  and a.comappstat! = b.comappstat)
  Set b.comappstat = a.comappstat
  
  Although I thought that the syntax is correct, I get an "ORA-00904: 'A'. '. ' COMAPPSTAT': invalid identifier ' to run this, I was trying to guess where the syntax was wrong here, then thought that perhaps having the subquery returns a single line would be cleaner and faster anyway, so I gave up on that and instead tried this:
  
  Update mnt.workorders_copy
  Set comappstat = (select distinct)
  a.comappstat
  mnt.workorders a, mnt.workorders_copy b
  where a.workordersoi = b.workordersoi
  and a.comappstat! = b.comappstat)
  where a.comappstat! = b.comappstat
  and a.workordersoi = b.workordersoi
  
  The subquery executed on its own returns a single value 9, which is the correct value of the column in the table of the prod, and I want to replace the incorrect a '12' (I've updated the copy to change the value of the column comappstat to 12 everywhere where it was 9) However when I run the query again I get this error :
  
  ERROR on line 8:
  ORA-00904: "B". "" WORKORDERSOI ": invalid identifier
  
  First of all, I don't see why the update statement does not work (it's probably obvious, but I'm not)
  
  Secondly, it is the best approach for updating a column (or columns) that are incorrect, with the columns in the same table which are correct, or is there a better way?
  
  I would sooner update the table rather than delete or truncate then re insert, as it was a trigger for insert/update I had to disable it on the notice re and truncate the table unusable a demand so I was re insert.
  
  Thank you

  Hello

  First of all, after post 79, you need to know how to format your code.

  Your last request reads as follows:

  UPDATE
    mnt.workorders_copy
  SET
    comappstat =
    (
      SELECT DISTINCT
        a.comappstat
      FROM
        mnt.workorders a
      , mnt.workorders_copy b
      WHERE
        a.workordersoi    = b.workordersoi
        AND a.comappstat != b.comappstat
    )
  WHERE
    a.comappstat      != b.comappstat
    AND a.workordersoi = b.workordersoi
  

  This will not work for several reasons:
  The sub query allows you to define a and b and outside the breakets you can't refer to a or b.
  There is no link between the mnt.workorders_copy and the the update and the request of void.

  If you do this you should have something like this:

  UPDATE
    mnt.workorders     A      -- THIS IS THE TABLE YOU WANT TO UPDATE
  SET
    A.comappstat =
    (
      SELECT
        B.comappstat
      FROM
        mnt.workorders_copy B   -- THIS IS THE TABLE WITH THE CORRECT (OLD) VALUES
      WHERE
        a.workordersoi    = b.workordersoi      -- THIS MUST BE THE KEY
        AND a.comappstat != b.comappstat
    )
  WHERE
    EXISTS
    (
      SELECT
        B.comappstat
      FROM
        mnt.workorders_copy B
      WHERE
        a.workordersoi    = b.workordersoi      -- THIS MUST BE THE KEY
        AND a.comappstat != b.comappstat
    )
  

  Speed is not so good that you run the query to sub for each row in mnt.workorders
  Note it is condition in where. You need other wise, you will update the unchanged to null values.

  I wouold do it like this:

  UPDATE
    (
      SELECT
        A.workordersoi
        ,A.comappstat
        ,B.comappstat           comappstat_OLD
  
      FROM
        mnt.workorders        A      -- THIS IS THE TABLE YOU WANT TO UPDATE
        ,mnt.workorders_copy  B      -- THIS IS THE TABLE WITH THE CORRECT (OLD) VALUES
  
      WHERE
        a.workordersoi    = b.workordersoi      -- THIS MUST BE THE KEY
        AND a.comappstat != b.comappstat
    ) C
  
  SET
    C.comappstat = comappstat_OLD
  ;
  

  This way you can test the subquery first and know exectly what will be updated.
  This was not a sub query that is executed for each line preformance should be better.

  Kind regards

  Peter

• Why Windows asks me to install the same updates several times. Often several times the same updates and often several times in the same day?

  I install security updates and important. Sometimes in the same day, I wonder to install the same updates. When I check the history I see that they are already installed. This can happen several times in the same day.

  Troubleshooting Windows Update or Microsoft Update when you are repeatedly offered an update

  UTC/GMT is 00:34 Sunday, March 11, 2012