ADFBC internal Tables - jdev 11.1.2.3 on redhat 5.8

Similar Questions

• GetValue in detail Table Jdev 11.1.2.3

  Hello:
  
  Using the HR schema:
  
  I created a page master/detail between departments and employees. Departments is a form and used in a table.
  
  As I browse the departments, employees are synchronized. This works well.
  
  One of the columns in the Employees table is HireDate, which is defined as a date in the database. Whenever I browse the departments, I need to run Java code
  who will read the value of hiring date, a date calculation (nouvelle_date = HireDate - 3 days) and displays this value nouvelle_date next to the HireDate column.
  
  For example:
  I sail the Department = 70, and she returns 8 rows for all employees of this Ministry. As these eight rows are returned, I need to get the hiring date input value
  perform the calculation of the 3 date and view this nouvelle_date next to hire date. Note: I would like to completely in the draft opinion. I know that I can change the template project ViewObject and this calculation.
  
  I tried to create a binding component on the hiring date, but does not seem that the getHireDate() method in the bean are triggered for each of the 8 records returned in my example above.
  Also called getValue () m:System.NET.SocketAddress.ToString () on the hiring date, does not seem to return the date value.
  
  What is the right way to run a java method once for each of the 8 records employee who returned when Dept = 70 as in my example above? And get the value of date of hire in Java?
  
  Thank you

  Is this related to {: identifier of the thread = 2510070}?

  You can not time to browsers in the model layer as long as you pass it as a parameter.

  Timo

• RichTreeTable.setSelectedRowKeys on the detail table - jdev 11.1.2

  Hello:
  I have a table with two levels of node tree (Oracle HR schema: a Department has many employees). The treetables works well. Inside a managed bean, I want to call treeTable.setSelectedRowKeys (RowKeySet) to the employee level and not at the level of the Department. Currently when I call this method it defines the line selected on the Department and not the employee. How can I call this method to highlight the line at the level of the employee?
  Thanks for the help of Experts. :)

  Hello

  detail rows are defined by a line which has the parent and the child key in it

  See http://www.oracle.com/technetwork/developer-tools/adf/learnmore/index-101235.html

  A sample 083 the code example on page 13 "onSubmitEmployeeForm()".

  Frank

• Deleting and adding incompatible line on af:table (Jdev version 11.1.1.5)

  Hello
  
  I have an af:table in which a Remove button to remove the selected current [(#{bindings.removeCurrentRow}) line].
  
  When remove us all of the rows in the Table and you try to add a new line by using the Add button (#{bindings.createInsertRow}).
  All the last line deleted column values are filled with new line.
  
  Note: This is reproducible when you delete all the rows that are displayed in the table and then try to add newline.
  
  Anyone knows similar question? Workaorunds all avalible?
  
  JDeveloper Version: 11.1.1.5.0
  
  Thank you
  Chaitanya

  Sounds like you hit similar issue discussed here (main cause is the same) - Re: restore operation fails on 11.1.1.5 . It was a correction of a bug in the latest version. Please contact your Oracle support

• How to reference a column internal table nested - without a name?

  Hi guys, I have a question about nested tables - Ive searched around and cannot find an answer.
  
  Here is my sample code:
  

  CREATE OR REPLACE TYPE scotttype AS table of number;
  
  create table scott1 (col_a varchar2(10), col_b scotttype) nested table col_b store as col_b
  
  insert into scott1 values ('onetwo',scotttype(1,2))
  
  insert into scott1 values ('threefour',scotttype(3,4))
  
  select t1.col_a, column_value col_b
  from scott1 t1, TABLE(t1.col_b) t2
  
  insert into table(select s.col_b FROM scott1 s WHERE s.col_a = 'onetwo')
  values (5);

  OK, so that sounds great.
  
  If I want to do an update or delete however, how can I make reference to col_b that the nested table doesn't have a column name?
  That is to say:
  
  

  update table(select col_b from scott1 where col_a = 'onetwo') col_b
  set col_b.XXXXX = 6
  where col_b.XXXXX = 5

  will then not work what should I put instead of the XXXXX?
  
  
  I'm sure its simple but I can't!
  
  Thank you all

  SQL> select t1.col_a, column_value col_b
    2  from scott1 t1, TABLE(t1.col_b) t2;
  
  COL_A           COL_B
  ---------- ----------
  onetwo              1
  onetwo              2
  threefour           3
  threefour           4
  onetwo              5
  
  SQL> commit;
  
  Commit complete.
  
  SQL> update table(select col_b c1 from scott1 where col_a = 'onetwo') t1
    2  set column_value = 6
    3  where column_value= 5;
  
  1 row updated.
  
  SQL> commit;
  
  Commit complete.
  
  SQL>  select t1.col_a, column_value col_b
    2   from scott1 t1, TABLE(t1.col_b) t2;
  
  COL_A           COL_B
  ---------- ----------
  onetwo              1
  onetwo              2
  threefour           3
  threefour           4
  onetwo              6
  
  SQL> 
  

• hash with very large internal table plan causes ORA-01652

  Hello
  
  We have a select with dubious plan:
  
  SELECT * FROM T1 where T1. F1 in (select T2. F1 T2)
  
  Plan:
  | ID | Operation | Name | Lines | Bytes | TempSpc | Cost |
  | 0 | SELECT STATEMENT | 59 M | 12G | 1 401 K |
  | 1. SEMI HASH JOIN | 59 M | 12G | 55G | 1 401 K |
  | 2. TABLE ACCESS FULL | T1 | 260 M | 52G | 489K |
  | 3. TABLE ACCESS FULL | T2 | 209K | 1843K | 84.
  
  As you see a record 260 million (52 GB) T1 and T2 has approximately 200,000 records (approximately 2 MB)
  Oracle chooses the hash with T1 inner table join. Thus all T1 is tempted to read first in memory.
  And when the memory is full, the TEMP tablespace is filled.
  And because the TEMP tablespace is less than 55 GB, an error has occurred:
  ORA-01652: unable to extend segment temp of 128 in tablespace TEMP
  
  Question:
  Why oracle choose the hash with inner table so big join?
  And how can we solve this problem?
  
  Other notes:
  T1 and T2 is analyzed today.
  Presumably no index or table.
  The database is Oracle 9i Enterprise.
  Description of Oracle 9i hash (first there are more small table as you can see):
  http://download.Oracle.com/docs/CD/B10501_01/server.920/a96533/optimops.htm#76074
  
  THX: sides.

  Hello

  Oracle 9i cannot make HASH JOIN RIGHT SEMI - were introduced in 10g.

  ----------------------------------------------------------------------------------------------------------------------------
  | Id  | Operation             | Name | Starts | E-Rows | A-Rows |   A-Time   | Buffers | Reads  |  OMem |  1Mem | Used-Mem |
  ----------------------------------------------------------------------------------------------------------------------------
  |   0 | SELECT STATEMENT      |      |      1 |        |      1 |00:00:55.73 |     162K|    162K|       |       |          |
  |   1 |  SORT AGGREGATE       |      |      1 |      1 |      1 |00:00:55.73 |     162K|    162K|       |       |          |
  |*  2 |   HASH JOIN RIGHT SEMI|      |      1 |   8147 |      0 |00:00:55.73 |     162K|    162K|   988K|   988K| 1031K (0)|
  |   3 |    TABLE ACCESS FULL  | T2   |      1 |     18 |     18 |00:00:00.01 |       3 |      0 |       |       |          |
  |   4 |    TABLE ACCESS FULL  | T    |      1 |     11M|     11M|00:02:09.99 |     162K|    162K|       |       |          |
  ----------------------------------------------------------------------------------------------------------------------------
  
  Predicate Information (identified by operation id):
  ---------------------------------------------------
  
     2 - access("OBJECT_NAME"="USERNAME")
  

• Update the range of Navigation in a table - Jdev 10.1.3.3

  Hello Comunity...
  
  I have an editable table where navigation is 1-15 i change the values in the table and navigate from 45-60, 60-75... and other lines, then I click button save that information is updated but the range navigation not. How can refresh the range at the top navigation.
  
  Thanks for the help.

  Hi Peter I post the solution last week.

  Add the following code in your bean support button Save:

  this.getTable1 () .setFirst (0);

  Where table.setFirst (0) sets the index of the first row in the current range of lines to the first record in the Table.

  Good luck.

• Invalid column Type error - Jdev 11.1.2.3 on Redhat 5.8

  Hello:
  
  I created a simple Web ADF application with a single table.
  
  Test1 uses the HR schema and the db connection is also HR and everything works fine.
  
  Test2 uses a (partner) schema that is different from the logged-in user (admininn) in about DB. In sqlplus, I can update the table as a logged-in user. For DB grants are ok.
  
  But in the ADF app, when I try an update, I get an error: exception for invalid column type. See error below.
  
  When the owner of the schema is different from the db connection, I get this error even if DB subsidies are in place. What Miss me?
  
  Thank you very much
  
  
  
  Note: the DB connection connects as admininn no PARTNER. But DB subsidies are in place to allow admininn associated schema update.
  
  [386] built select: "SELECT CLI_KEY, CLI_NAME, CLI_SHORT_NAME, CLI_TYPE, CLI_LAWSON_ID, CLI_ACTIVE, CLI_COUNTRY PARTNER. CLIENTS Clients
  [387] enforcement of LOCKING... SELECT CLI_KEY, CLI_NAME, CLI_SHORT_NAME, CLI_TYPE, CLI_LAWSON_ID, CLI_ACTIVE, CLI_COUNTRY PARTNER. The CUSTOMERS Customers WHERE CLI_KEY =: 1 FOR UPDATE NOWAIT
  [388] where the link param 1:263
  OracleSQLBuilderImpl.doEntitySelect [389] failed...
  [390] java.sql.SQLException: invalid column type
  at oracle.jdbc.driver.OraclePreparedStatement.setObjectCritical(OraclePreparedStatement.java:11256)
  at oracle.jdbc.driver.OraclePreparedStatement.setObjectInternal(OraclePreparedStatement.java:10605)
  at oracle.jdbc.driver.OraclePreparedStatement.setObjectInternal(OraclePreparedStatement.java:11665)
  at oracle.jdbc.driver.OraclePreparedStatement.setObject(OraclePreparedStatement.java:11631)
  at oracle.jdbc.driver.OraclePreparedStatementWrapper.setObject(OraclePreparedStatementWrapper.java:253)
  at oracle.jbo.server.OracleSQLBuilderImpl.bindWhereAttrValue(OracleSQLBuilderImpl.java:2306)
  at oracle.jbo.server.BaseSQLBuilderImpl.bindWhereClause(BaseSQLBuilderImpl.java:2300)
  at oracle.jbo.server.EntityImpl.bindWhereClause(EntityImpl.java:10784)
  at oracle.jbo.server.BaseSQLBuilderImpl.bindWhereClause(BaseSQLBuilderImpl.java:2283)
  at oracle.jbo.server.OracleSQLBuilderImpl.doEntitySelectForAltKey(OracleSQLBuilderImpl.java:840)
  at oracle.jbo.server.BaseSQLBuilderImpl.doEntitySelect(BaseSQLBuilderImpl.java:552)
  at oracle.jbo.server.EntityImpl.doSelect(EntityImpl.java:8311)
  at oracle.jbo.server.EntityImpl.lock(EntityImpl.java:5971)
  at oracle.jbo.server.EntityImpl.beforePost(EntityImpl.java:6491)
  at oracle.jbo.server.EntityImpl.postChanges(EntityImpl.java:6707)
  at oracle.jbo.server.DBTransactionImpl.doPostTransactionListeners(DBTransactionImpl.java:3264)
  at oracle.jbo.server.DBTransactionImpl.postChanges(DBTransactionImpl.java:3067)
  at oracle.jbo.server.DBTransactionImpl.commitInternal(DBTransactionImpl.java:2071)
  at oracle.jbo.server.DBTransactionImpl.commit(DBTransactionImpl.java:2352)
  at oracle.adf.model.bc4j.DCJboDataControl.commitTransaction(DCJboDataControl.java:1590)
  at oracle.adf.model.binding.DCDataControl.callCommitTransaction(DCDataControl.java:1415)
  at oracle.jbo.uicli.binding.JUCtrlActionBinding.doIt(JUCtrlActionBinding.java:1428)
  at oracle.adf.model.binding.DCDataControl.invokeOperation(DCDataControl.java:2169)
  at oracle.jbo.uicli.binding.JUCtrlActionBinding.invoke(JUCtrlActionBinding.java:731)
  at oracle.jbo.uicli.jui.JUActionBinding.actionPerformed(JUActionBinding.java:193)
  at oracle.jbo.uicli.controls.JUNavigationBar.doAction(JUNavigationBar.java:412)
  at oracle.jbo.jbotester.NavigationBar.doAction(NavigationBar.java:112)
  to oracle.jbo.uicli.controls.JUNavigationBar$ NavButton.actionPerformed (JUNavigationBar.java:118)
  at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
  in javax.swing.AbstractButton$ Handler.actionPerformed (AbstractButton.java:2318)
  at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
  at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
  at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
  at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:272)
  at java.awt.Component.processMouseEvent(Component.java:6289)
  at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
  at java.awt.Component.processEvent(Component.java:6054)
  at java.awt.Container.processEvent(Container.java:2041)
  at java.awt.Component.dispatchEventImpl(Component.java:4652)
  at java.awt.Container.dispatchEventImpl(Container.java:2099)
  at java.awt.Component.dispatchEvent(Component.java:4482)
  at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4577)
  at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4238)
  at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4168)
  at java.awt.Container.dispatchEventImpl(Container.java:2085)
  at java.awt.Window.dispatchEventImpl(Window.java:2478)
  at java.awt.Component.dispatchEvent(Component.java:4482)
  at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:644)
  to java.awt.EventQueue.access$ 000 (EventQueue.java:85)
  in java.awt.EventQueue$ 1.run(EventQueue.java:603)
  in java.awt.EventQueue$ 1.run(EventQueue.java:601)
  at java.security.AccessController.doPrivileged (Native Method)
  in java.security.AccessControlContext$ 1.doIntersectionPrivilege(AccessControlContext.java:87)
  in java.security.AccessControlContext$ 1.doIntersectionPrivilege(AccessControlContext.java:98)
  in java.awt.EventQueue$ 2.run(EventQueue.java:617)
  in java.awt.EventQueue$ 2.run(EventQueue.java:615)
  at java.security.AccessController.doPrivileged (Native Method)
  in java.security.AccessControlContext$ 1.doIntersectionPrivilege(AccessControlContext.java:87)
  at java.awt.EventQueue.dispatchEvent(EventQueue.java:614)
  at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
  at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
  at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
  at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
  at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
  at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)

  Check the OS type for each attribute. Number should be oracle.jbo.domain.Number.
  VARCHAR must be java.lang.String. Date should be oracle.jbo.domain.Date

• Jdev 11.1.2.3 on RedHat 5.8 - question about ADF Libs

  Hello: I am following the use ADF Libs method to separate the common code of the various subsystems. So I created the following bookstores: CommonCode, CommonModel, CommonUI. This large all worked.
  
  So now, I'm working on the creation of two subsystems that everyone uses common libraries of adf. Each subsystem will also create their own pot of lib adf. It worked.
  
  But...
  I have a two tables joined by a relationship master detail I want to test. I VO for the main table in subsystem1 of installation and configuration VO for detail in subsystem2 table. Where would the display link? Subsystem1 or subsystem2. Is how important it?
  
  The next step would be to create an Application of master using subsystem1 and subsystem2. In the master application, I would like to develop the relationship master detail between the tables and perform a test. In theory, no code should go in the Master. Right?
  
  So where the display link should go? Subsystem1, subsystem2 or master. And what is the rationale?
  
  Thanks for the help.

  Hello

  You may not create any links on any of the projects because this relationship between subsystems is only valid under the Master application. Therefore, the link must be created on the request of the master, after that both libraries have been imported, keep in mind that after you import the two libraries you mark them as shared AMs under the master AM also if you have an optimal control over db how instances are created. See the article according to that described a similar approach
  http://www.Oracle.com/technetwork/developer-tools/ADF/learnmore/87-lov-using-shared-am-444769.PDF

  Juan Camilo

• ADFLibs Fusion Web App - Jdev 11.1.2.3 on redhat 5.8

  Hello:
  
  Say I have create a Web of Fusion ADF application called APP_LIB. This app has EO, VO, AM in the model project and has Pages, fragments and the Taskflows in the ViewController. I want to create an APP_LIB Lib ADF, so I create a deployment profile ADF Lib on the ViewController project. The ViewController being dependant on the model project, the library must be created with EO, VO, AM, Pages, Fragments and some TaskFlows. Right? Or I would create different profiles of deployment for the model and the ViewController project and thus 2 create two separate ADF Libs?
  
  Now, I want to import the ADF of APP_LIB lib into another ADF Fusion Web application called ENTERPRISE_APP. If I imported the ViewController of ENTERPRISE_APP the APP_LIB, would be the EO, VO and AM appear in the model project? Or do I have to import APP_LIB into the project template and ViewController of ENTERPRISE_APP?
  
  Is it better to separate libraries for the project template and ViewController in APP_LIB and create two separate ADF Libs for the model and ViewController? What the experts recommend creating the ADF libs on a project template project and project ViewController and also what is the best way to import the ADF LIB in a Fusion ADF application that also has a model project and the ViewController project.
  
  Can I create two ADF Libs: a Lib ADF for the project template and a Lib ADF for the ViewController and import each project ADF Lib in (model and ViewController) correspondent business APP?
  
  Any recommendations?
  
  Thank you very much.

  Hello

  This is what Oracle Fusion Applications as well. Keep in mind that the ADF libraries are not contained in other libraries, which means that the "Assembly" application requires references from the library in the project view controller

  Frank

• Jdev 11.1.2.3 on RedHat 5.8 - use ADF Fusion Proj for Master

  Hello:
  I'm in accordance with the practice of creating shared libraries of ADF for model, the Code and the user interface, called CommonModel, CommonCode, CommonUI.
  Developers create subsystem projects that import these Libs ADF. Then several subsystems (such as ADF Libs) are combined into a master application that then creates the EAR file for deployment.
  
  Each of the subsystems are ADF Fusion Web Apps. (a model and viewController projects)
  Shared libraries are Custom apps. (with only a single project)
  
  The Question is what type of application to create for the Master project. The docs seem to indicate a custom project, but I think it's wrong and that I have to use a Web of Fusion ADF application for the master who would model and viewController projects.
  
  So, what type of application must be created for the master? Custom = a project or ADF Fusion app that has 2 projects (model and viewController)?
  
  Thanks for the help.

  Hello

  Keep in mind that the types of applications are a few models. Models include a set of libraries of different technologies that you can work on your project. However that does not limit you to use other technologies or libraries outside of this scope. Custom type is open to all.

  Juan C

• configuration server weblogic internal Jdev 11 g

  We try to use admin console internal server Jdev 11 g weblogic
  We localhost/7101 port.
  Thne when we open the following error consele occurs on the page web consele.
  'Unable to render framework/skeletons/wlsconsole/window.jsp.
  
  Thanks for your help...

  It seems that the problem might be related to language settings of your local machine. A search on the error message: "the windowpc type is not a valid type for the context tag" reveals the post following the RTO. Check you to read to the bottom of the post for the solution:

  Re: Can not connect to the Console of administration of Server WebLogic 10.3 (with Jdev11g)

  CM.

• < table > < col > - tag error rendered attribute valign

  Hello!

  I guess it must be a bug in Firefox 11.0 (?):

  I have a Web page with tables within a table. Internal tables have the following tags:

  The page is here: www.transformation.dk/indextest.html

  The first column contains a short word (1 line). The second column contains text that can be run on several lines.

  In MS - IE 9.0 tags above result in the short term in the first column being repeat is aligned with the first line of the text in the second column.
  But in Firefox 11.0, the word in the first column is much further down.

  If anyone has experienced this?
  Should I file it as a bug here: https://bugzilla.mozilla.org/

  Best regards
  Hero27

  The Mozilla Developer Network site discourages the use of < col > application valign of individual cells: col-MDN.

  Without delving too deeply into your content, would it not be simpler set a higher overall alignment in CSS?

  
  td, th {vertical-align:top;}
  

• No limitation regarding the table of bitmaps?

  I'm working on a game. Previously, I had 13 executives of sprite as separate files and used getBitmapResource to load into an array of bitmaps. It worked well.

  I've upped the number of sprite images to 26 and make them in a single bitmap file with 2 rows of 13 (corresponding to the States of game). I'm trying to load them into an array of Bitmaps - either one or two dimensions. None worked. The last loaded image is one that is displayed, regardless of what I call for. I use Bitmap.scaleInto, in OS5.

  My attempts at debugging continue to wonder if I'm violating a rule, with the berries of the Bitmap. Like, the berries can only work before because of the structure of the .png files? Bitmaps are already in an internal table format that blends in with my paintings?

  I can also have incorrectly implemented the scaleInto, although I'm working with the code for a very good post on this forum. Here is that code, currently configured to use a single dimension table. There are a few more from the referenced post lines, to maintain transparency in the sprite frames.

  class Thing extends OBJ
  {
   static Bitmap[] _mySprite; 
  
   Thing(int passX, int passY)
     {
      super(passX, passY);
  
      // Set bitmaps
  
      Bitmap multi_sprite = Bitmap.getBitmapResource("sprite_64x29.png");
      _mySprite = new Bitmap[26];
  
      Bitmap image = new Bitmap(Bitmap.ROWWISE_16BIT_COLOR, 64, 29);
      image.createAlpha(Bitmap.ALPHA_BITDEPTH_8BPP);
      for (int y = 0; y < 2; y++) {
          for (int x = 0; x < 13; x++) {
              int[] transparentImage = new int[64 * 29];
              image.setARGB(transparentImage, 0, 64, 0, 0, 64, 29);            multi_sprite.scaleInto(x*64, y*29, 64, 29, image, 0, 0, 64, 29, Bitmap.FILTER_LANCZOS);           _mySprite[x+13*y] = image;
             }
         }...
  

  Transparency works. And, if I shorten the loop values, the last loaded picture appears, regardless of what image I try to get out of the table.

  I know that I could skip the drawBitmap preload and only when needed. But I have a lot of code in place that expects to be able to check the dimensions of several bitmaps, in addition to these. And it seems just cleaner to shorten them.

  you re-use the image object, most likely, you end up with a table of the same objects (a table only refers to the object, it does not copy it).

• The external Table storage

  Since data is stored outdoors, and the definition that is stored inside, it means that a the table structure of the outer table is stored in the database as well (or a virtual table based on the definition of the external table...)

  I'll hit the ORA-DOCS again once, back in the external tables read tonight on them 2 or 3 sources and it is not quite clear whether real data with structure exists outside the database or an internal table set (and stored) retrieves data from an outside source.

  Since data is stored outdoors, and the definition that is stored inside, it means that a the table structure of the outer table is stored in the database as well (or a virtual table based on the definition of the external table...)

  The 'definition' you refer to IS the structure of the table; they are one and the same. There is no 'table' stored in the database using space or storage. When a query on an external table is executed, the data source is read.

  
  I'll be hitting the ORA-DOCS up again, just got back into external tables tonight reading up on them from 2-3 sources and it is not quite clear if an actual data with structure exists out of the database , or an internally defined (and stored?) table draws data from an outside source.
  

  I suggest you that start with the documentation of Oracle - including the ground provided the link to:

  If any "metadata" are stored outside the database depends on if the file that is outside of the database was produced by Oracle using the robot UNLOADING discussed in this doc

  Unloading of data using ORACLE_DATAPUMP Access driver

  To unload data, you use the ORACLE_DATAPUMP driver access. The stream that is discharged is in a proprietary format and contains all of the data column for each row being unloaded.

  A discharge operation also creates a stream of metadata that describes the content of the data stream. The information in the metadata stream are required to load the stream. Therefore, the metadata stream is written to the file data and placed before the data stream.

  If YOU provide data/files, then you MUST provide it in the format expected by the external table statement. You can, if you wish, use a preprocessor to convert ANY file (zip, encrypted, etc.) in the required format.

  For YOUR files, you can the metadata stored in the same file, or elsewhere, if you choose, but Oracle will have NO knowledge of this fact and not will NOT be involved in the transformation or read any of the metadata that you provide. Your preprocessor must remove all these metadata and ONLY provide data in the format appropriate for Oracle to use.

  If the file was produced by the process of UNLOADING Oracle then it will include metadata that Oracle WILL read, use, and remove as says this quote from doc above. These external metadata is added to the real external table definintion/metadata stored in the dictionary.