explain plan before and after?

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• Why is there a commit implied before and after execution of DDL statements

  Hi guys,.
  
  Please let me know why he didn't is committed before and after the execution of DDL statements implied?
  
  
  Kind regards
  Sushmita

  Helyos wrote:
  This is because Oracle has the design like that.

  Come on Helyos, which is somewhat a weak response. :)

  The reason is that it is foolish to update the structure of the database, while there are some missing data updates that have not been committed.

  Imagine having a column VARCHAR2 (50), which currently has data of size up to 20 characters.
  Someone (person A) Decides that it would be useful to change the table and reduce the size of the varchar2 column (20) instead.
  Before they do, a third party (person B) inserted data that are 30 characters in size, but not yet committed it.
  In regard to person B is concerned and that the Insert succeeded as they don't got no error message, and they continue on through their process until they reach a suitable to commit point.
  Person that has and then tries to modify the database to make varchar2 (20).

  If the database has allowed that to happen then the column would be varchar2 (20) and the uncommitted data is more, even if the insertion was successful. When person B is going to know about it? It would be wrong to tell them when they try and commit, because their operations have succeeded, so why commit would fail.

  In this case, because it's two different people, then the database will recognize there are transactions that are uncommitted on the table and don't let anyone B change it.

  If it was just one person doing the two things in the same session, then the data would be automatically validated, the executed alter and the person has indicated that they can change the database because it is (now) data over the size that they want to.

  It makes perfect sense to have the database in a consistent state of data before changes are made, so why a commit is issued in advance.

  Here's something I wrote the other day on the subject...

  DOF delivers a validation before performing the actual action
  As long as the DOF is syntactically ok (the parser is happy with it), then the validation is issued, even if the actual DDL cannot be performed for another reason.

  For example...

  We have a table with data in there...

  SQL> create table xtest as select rownum rn from dual;
  
  Table created.
  
  SQL> select * from xtest;
  
          RN
  ----------
           1
  

  We then delete the data but do not commit (demonstrated by the fact that we can roll it back)

  SQL> delete from xtest;
  
  1 row deleted.
  
  SQL> select * from xtest;
  
  no rows selected
  
  SQL> rollback;
  
  Rollback complete.
  
  SQL> select * from xtest;
  
          RN
  ----------
           1
  
  SQL> delete from xtest;
  
  1 row deleted.
  
  SQL> select * from xtest;
  
  no rows selected
  

  So now, our data are deleted, but not committed, what happens if we issue a DOF that is syntactically incorrect.

  SQL> alter tab xtest blah;
  alter tab xtest blah
        *
  ERROR at line 1:
  ORA-00940: invalid ALTER command
  
  SQL> rollback;
  
  Rollback complete.
  
  SQL> select * from xtest;
  
          RN
  ----------
           1
  

  ... data can always be restored. This is because the parser was not happy with the syntax of the DDL statement.

  So let's delete the data again, without commit and deliver a DOF that is syntactically correct, but cannot run for another reason (i.e. the database object it refers to does not exist)...

  SQL> delete from xtest;
  
  1 row deleted.
  
  SQL> select * from xtest;
  
  no rows selected
  
  SQL> truncate table bob;
  truncate table bob
                 *
  ERROR at line 1:
  ORA-00942: table or view does not exist
  
  SQL> rollback;
  
  Rollback complete.
  
  SQL> select * from xtest;
  
  no rows selected
  

  So, there we have it. Just because the statement is syntactically correct, the deletion of the data has been committed, even if the DOF could not be performed.

  It makes sense really, because if we intend to amend the definition of the database where the data is stored, it cannot take place unless the database is in a State where the data is where it should be instead of being in limbo. For example, imagine the confusion if you update data on a column and then changed the data type of columns to be of a different size, for example reducing a column varchar2 50 characters up to 20 characters. If you had data that had just updated you to more than 20 characters whereas previously it was not, then the alter table command cannot not on this subject, which could alter the size of the column and then the data would be invalid to adapt while the update at the time did not fail.

  For example...

  We have a table that allows only 20 characters in a column. If we try to insert them more in this column, you get an error for our insert as planned...

  SQL> create table xtest (x varchar2(20));
  
  Table created.
  
  SQL> insert into xtest values ('012345678901234567890123456789');
  insert into xtest values ('012345678901234567890123456789')
                            *
  ERROR at line 1:
  ORA-12899: value too large for column "SCOTT"."XTEST"."X" (actual: 30, maximum: 20)
  

  Now, if our table has allowed more character our insert statement are successful. As far as our 'application' is going to believe us, nay, we were told of the database, we have successfully introduced our data...

  SQL> alter table xtest modify (x varchar2(50));
  
  Table altered.
  
  SQL> insert into xtest values ('012345678901234567890123456789');
  
  1 row created.
  

  Now, if we tried to change our database column date back to 20 characters and it did not automatically the data beforehand then it would be happy to edit the column, but then when the data has been committed he wasn't. However the database has already told us that the data were inserted, so he can't go back to that now.

  Instead, we can see that the data be engaged first because the alter command returns an error telling us that the table data is too large, and also can not restore the insertion after the alter attempt...

  SQL> alter table xtest modify (x varchar2(20));
  alter table xtest modify (x varchar2(20))
                            *
  ERROR at line 1:
  ORA-01441: cannot decrease column length because some value is too big
  
  SQL> rollback;
  
  Rollback complete.
  
  SQL> select * from xtest;
  
  X
  --------------------------------------------------
  012345678901234567890123456789
  
  SQL>
  

  Of course, being a statement commit to the existing session, if we had tried to modify the column of the table to another session would have got us

  SQL> alter table xtest modify (x varchar2(20));
  alter table xtest modify (x varchar2(20))
  *
  ERROR at line 1:
  ORA-00054: resource busy and acquire with NOWAIT specified
  
  SQL>
  

  ... which is basically saying that we cannot change the table because someone else uses it and they did not commit their data still.

  Once the other session committed data, we obtain the expected error...

  ORA-01441: cannot decrease column length because some value is too big
  

  Hope that explains it

• HP 5510 will be not printed black before and after you installed the new cartridge. the specified controls did.

  Photosmart HP 5510 will be not printed black before and after you installed the new cartridge.  The specified controls did.

  Yes, I was referring to manually clean the print head. I see that the 5510 lacks the possibility of leaving the print head manually.
  
  You can click on the menu of your SETUP program on your screen and go to TOOLS and clean the print head from there.
  
  If this does not resolve your problem, you may need to replace the print head.
  Contact HP Total Care (1800-474-6836), and if your unit is under warranty, its free.
  
  Let me know if this can help, thank you.

• How can I add points mark before and after every comma in TextEdit?

  Hello world

  I have a fairly big translation file CSV that I need to change and I'm wondering how to do this without having to do it manually.

  I want to add points mark before and after every comma of the document.

  Currently, my text looks like this:

  Account information, information of the affiliate account, affiliate

  Credit, Credit affiliate, affiliate

  Membership discount, discount affiliate,

  Email, e-mail address of the affiliate membership,

  Home membership, Affiliation home,

  Link, affiliate link, affiliate

  Affiliate Login, login affiliate,

  Name, name of the affiliate, affiliate

  Affiliate, affiliate,

  And I need it to be like this:

  "Total account", "Account balance",

  "Reach account balance', ' the account balance - door."

  "Account setup", "Account setup",

  "E-mail account", "E-mail account",

  "Account Information", "Account information",

  'Account Manager', 'Account manager',

  'New account', 'New account',

  'Account settings', 'Account settings',

  Tips that would help me to do it is more than welcomed.

  Thank you!

  I suggest the 'best' way to do may not be via AppleScript itself.

  AppleScript can do, but his text, the analysis is heavy, while the shell commands handle this with ease (although they are not as easy to read).

  That said, here is an example of AppleScript - the converted text will be written to the file "output.csv" on your desktop.

  game dittos to (Choose file)

  the value of output of {}

  the value question in paragraphs of (read (dittos) as text)

  Repeat with eachPara in question

  the value my entry point text delimiters to ",".

  the value $thisline for text elements of eachPara

  the value my text item delimiters to quote & "," & quote

  copy (quote & ($thisline as text) & quote) to end of output

  the value my point text delimiters to ASCII character 10

  set this to output as text

  end Repeat

  game of outputFile to (open access file ((path to the Office as text) & 'output.csv' in the text) with write permission)

  outputFile folklore of the value to 0

  write this as text to outputFile

  outputFile close access

  As you can see, it is heavy, especially compared to a few lines of shell script, but it should you get.

• HP LaserJet M2727 MFP Series PCL 6 - prints the blank page before and after each document in all cases

  HP LaserJet M2727 MFP Series PCL 6
  prints blank page before and after each document in all cases
  Does anyone else have this problem.

  It must be a preference setting, but I watched three times and CAP does not seem to determine what setting to change.

  See if they help you:

  http://h20000.www2.HP.com/bizsupport/TechSupport/document.jsp?lang=en&cc=us&ObjectID=c01477176&prodTypeId=18972&prodSeriesId=3377075

  http://h30499.www3.HP.com/T5/printers-LaserJet/LaserJet-M2727-NF-can-I-suppress-blank-pages-with-this-printer/TD-p/2359555

  http://superuser.com/questions/315522/computer-prints-blank-pages-before-and-after-content

• OfficeJet 4500 noisy before and after printing

  My Officejet 4500 G510 is suddenly very hard before and after printing. A repetitive noise quickly (like a submachine gun) turns on for about 5 seconds before and after printing. The printer and a screw brouilla's reversed. Can not see where it came from, after having carefully considered in back and front compartments. But the noise was still prints OK, I have to go!

  Thank you for advice or comments.

  I'm sorry you have a problem with the loud noise with the printer.

  Try to perform a hard reset on the printer. Unplug the power cord at the back. Leave for 30 seconds and plug it back.

  This screw is perhaps the problem on it. It may be a piece that is stuck and make transport to slam against the wall.

  Try to see if something prevents the transport to move freely.

• before and after the shows difference in white balance even if the photo is not published

  My present Lightroom (white balance) differences between before and after images of the same file, even when the image was published not (the front of the image seems greener). I already checked my import settings and there is no editing during import. The two images, before and after should look exactly the same, but they don t. I have amd using a PC and my files is Nikon Raw or jpeg, it is not serious, the same product no matter the file type.

  

  This is probably due to a faulty monitor profile.

  Windows 10 is known to install the manufacturer profiles, which are often of poor quality.

  Troubleshooting, as well as a temporary fix, try to set the monitor to sRGB profile.

  I have this solves the problem, ideally you should calibrate your monitor with a standard material.

  Press the Windows key + R, type colorcpland press ENTER.

  Add the sRGB profile, and then set as default profile. See screenshot (from Windows 7) below.

  

• Before and after Trobleshoot

  As I imported the folder with all of my photos from one computer to another, the edited images are read by lightroom as the originals, which means that in developer mode 'before and after', the edited image will appear as before and after. Can I reset the settings of the image and the 'before' image remains with the changes. I'd appreciate any help using lightroom to choose the original instead of the edited image.

  danyar60583326 wrote:

  As I imported the folder with all my photos from one computer to another,

  This seems to be the starting point of the problem. Import a second time, it is almost never a good idea. See this link to correctly move LR from one computer to another:

  How can I move Lightroom to a new computer? Lightroom Queen

• Before and after the split-screen view

  Its possible for itself before and after without split-screen? Just pass before and after.

  Not to be confused with the key slash?

• How to get the part of string before and after a character

  Hi all

  How to get the string before and after the comma character)

  Ex: The string contains the value John Kennedy

  I need the output as first stirng - John

  Second stirng - Kennedy

  Create table names (fullname varchar2 (20));

  insert into values of names ("John, Kennedy");

  insert into values of names ("papa ibra, Shan");

  insert into values of names ('Don Bosco'),

  Select * from names;

  Expected results

  FullName firstname lastname

  John, Kennedy John Kennedy

  Nicolas, Nicolas Shan Shan

  Don Bosco Don Bosco

  Please let me know how to proceed

  Thank you

  Hello

  This proves what I said before, on 0 and several commas commas.

  If we add these 3 rows to the sample data you posted:

  insert into names (fullname) values ("tou").

  insert into names (fullname) values (' David, Lloyd, George ");

  insert into names (fullname) values ('J, R, R, Tolkien");

  then the query I posted earlier produced these results:

  FULLNAME FIRSTNAME LASTNAME

  -------------------- -------------------- --------------------

  John, Kennedy John Kennedy

  Nicolas, Nicolas Shan Shan

  Don Bosco Don Bosco

  TOU tou

  David Lloyd, George David Lloyd, George

  J, R, R, Tolkien J R, R, Tolkien

  If you prefer to get these results:

  FULLNAME FIRSTNAME LASTNAME

  -------------------- -------------------- --------------------

  John, Kennedy John Kennedy

  Nicolas, Nicolas Shan Shan

  Don Bosco Don Bosco

  TOU tou

  David Lloyd, George David, Lloyd George

  J, R, R, J, R, R Tolkien Tolkien

  then you just change line 1:

  WITH got_commapos AS

  (

  SELECT FullName

  , INSTR (fullname, ','-1) AS commapos-* CHANGED *.

  Names

  )

  SELECT FullName

  , SUBSTR (fullname, commapos 1, -1) AS a first name

  SUBSTR (fullname, commapos + 1) in the FORM name

  OF got_commapos

  ;

• Before and after the problem - Module Development - Windows 7, 64-bit - Lightroom CC v. 2015.5 - camera raw 9.5

  I use Windows 7 64-bit, Lightroom CC 2015.5 Camera Raw 9.5 and the module development on a feature photo ' before and after ' does not work.

  He shows me the image changed, but not the original (I don't know exactly what another image "edited", it shows me).

  In the screen shot, you can see the pictures "before and after" and the one original overxposed.

  I hope I am clear enough.

  Any suggestion?

  

  Thank you :-)

  Click with the RIGHT button ON the import step in HISTORY (do click NOT just what this will change your photo AFTER) and select "copy history step settings to before.

  "

• How to check before and after in Photoshop?

  Is there a cursor function "before and after", etc. plugin Photoshop cs6 that allows you to see a slider from left to right before and after the image in meansf?

  Hi gropius,.

  From now there is no option if Photoshop to check the image in Photoshop, before and after.

  However, you can consult the following links, they might be useful: Photoshop shortcut: view Original | PhotographyBB

  any keyboard shortcut for comparing before after in photoshop cs3: retouching Forum: Digital Photography Review

  Let me know if it helps.

  Kind regards

  Tanuj

• Before' and 'After' query

  I think I'm misunderstanding of the use of 'Y' on the keyboard.

  When you view a photo retouched full screen, I would also like to be able to see in it's unpublished, before, form.

  When I press on 'Y' I get either a beep or a message indicating that I did not choose a photo.

  I know that I can see the before and after with the buttons below, but I had the impression that "Y" would serve the purposee.

  

  Clarification would be appreciated.

  Cliff

  When you view a photo retouched full screen, I would also like to be able to see in it's unpublished, before, form.

  When I press on 'Y' I get either a beep or a message indicating that I did not choose a photo.

  Are working in the develop Module. I can't Y paged me.

• L7680 ejects blank Page before and after print job

  My L7680 has recently started to eject a blank page before and after a print job; separator page option is NOT selected.  I have tried all the suggested trouble shooting points in the HELP section, but none solved the problem.

  The button Configure the printer had the option to return all the default values - that solved the problem, but it takes you to set other choices that you have made since you use the legacy.

• How to prune a white space before and after the bookmarks?

  Hello

  I hope that someone can help me with some JavaScript to remove the spaces before and after my favorites. I know I have to use regular expressions which I think would be ^ [\t]+| [\t]+$ and I also found a code on the internet but it is related to not favorite channels.] How would change this code work for bookmarks? Thank you.

  // Trim
  function trim(stringToTrim){
  return stringToTrim.replace(/^\s+|\s+$/g,””);
  }
  

  First of all, for this code to work, you must use standard double quotes, not the ones you currently have it.

  For use on a bookmark, you can do something like this:

  var bkm = this.bookmarkRoot.children[0];
  bkm.name = trim(bkm.name);