Table design, best way?

I have two tables that describes a schedule. the first table contains:
table: Event
EventID
Time_stamp
Action
table: Event_units
EventID
UnitID
There are some events that need to be associated with multiple units.
I get the EventID from a sequence that I have created. Does anyone see any problems with this design or a better way to do it? The problem right now is I insert into the Events table first and the eventID is inserted by a trigger after the insert. Next I insert into the Event_units table. What I am worried about is that if another event is added to the Event table before I do the insert, eventID wont be right(see below). Is there any way when I do the insert that sequence I assigned to it is returned to my code?
INSERT INTO EVENT .. (app 1)
INSERT INTO EVENT .. (app 2)
INSERT INTO EVENT_UNITS .. (app 1)
null

Sure is! You can do it like this.
DECLARE
lv_Event_Id
BEGIN
INSERT INTO Event VALUES (sequence_name.nextval, SYSDATE, 'Big hoedown at the Buckley manor') RETURNING EventID INTO lv_Event_Id;
INSERT INTO Event_Units VALUES (lv_Event_Id, 5);
COMMIT;
END;
There you go! Returning is great sometimes. :)

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[JHeadstart 10.1.3 build 78]
[JDeveloper 10.1.3 SU4]
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16:01:01 DEBUG (JhsPageLifecycle) -executing onCreate
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2006-08-02 16:01:01.825 WARNING [ADFc] Warning: No Method onCreateEmployees and no actionBinding CreateEmployees found.
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<?xml version="1.0" encoding="windows-1252"?>
<!DOCTYPE faces-config PUBLIC
"-//Sun Microsystems, Inc.//DTD JavaServer Faces Config 1.1//EN"
"http://java.sun.com/dtd/web-facesconfig_1_1.dtd">
<faces-config xmlns="http://java.sun.com/JSF/Configuration">
<managed-bean>
<managed-bean-name>CreateEmployeesDefaultValues</managed-bean-name>
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<managed-bean-scope>request</managed-bean-scope>
<managed-property>
<property-name>iteratorBinding</property-name>
<value>#{bindings.EmployeesIterator}</value>
</managed-property>
<managed-property>
<property-name>defaultValues</property-name>
<map-entries>
<map-entry>
<key>Salary</key>
<value>#{data.DefaultValuesPageDef.DefaultValuesIterator.currentRow.Salary}</value>
</map-entry>
</map-entries>
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<managed-property>
<property-name>actionResult</property-name>
<value>CreateEmployees</value>
</managed-property>
</managed-bean>
<managed-bean>
<managed-bean-name>searchEmployees</managed-bean-name>
<managed-bean-class>oracle.jheadstart.controller.jsf.bean.JhsSearchBean</managed-bean-class>
<managed-bean-scope>session</managed-bean-scope>
<managed-property>
<property-name>bindings</property-name>
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<property-name>searchBinding</property-name>
<value>#{data.EmployeesPageDef.advancedSearchEmployees}</value>
</managed-property>
<managed-property>
<property-name>searchAttribute</property-name>
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<managed-bean>
<managed-bean-name>EmployeesCollectionModel</managed-bean-name>
<managed-bean-class>oracle.jheadstart.controller.jsf.bean.JhsCollectionModel</managed-bean-class>
<managed-bean-scope>request</managed-bean-scope>
<managed-property>
<property-name>jhsPageLifecycle</property-name>
<value>#{jhsPageLifecycle}</value>
</managed-property>
<managed-property>
<property-name>bindings</property-name>
<value>#{bindings}</value>
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<managed-property>
<property-name>rangeBinding</property-name>
<value>#{bindings.EmployeesTable}</value>
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<managed-property>
<property-name>defaultValues</property-name>
<value>#{CreateEmployeesDefaultValues.defaultValues}</value>
</managed-property>
</managed-bean>
</faces-config>
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<?xml version='1.0' encoding='windows-1252' ?>
<!DOCTYPE ViewObject SYSTEM "jbo_03_01.dtd">
<ViewObject
Name="DefaultValues"
BindingStyle="OracleName"
CustomQuery="true"
ComponentClass="hr.model.DefaultValuesImpl"
UseGlueCode="false" >
<DesignTime>
<Attr Name="_version" Value="10.1.3.36.73" />
<Attr Name="_codeGenFlag2" Value="Access|Coll|VarAccess" />
</DesignTime>
<ViewAttribute
Name="Salary"
IsUpdateable="false"
IsPersistent="false"
Precision="255"
Type="java.lang.String"
ColumnType="VARCHAR2"
AliasName="SALARY"
Expression="1000"
SQLType="VARCHAR" >
</ViewAttribute>
</ViewObject>
The PageDef for Defaultvalues is like:
<?xml version="1.0" encoding="UTF-8" ?>
<pageDefinition xmlns="http://xmlns.oracle.com/adfm/uimodel"
version="10.1.3.36.73" id="DefaultValuesPageDef"
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<parameters/>
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<Item Value="Salary"/>
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<action id="PreviousDefaultValues" IterBinding="DefaultValuesIterator"
DataControl="AppModuleDataControl" RequiresUpdateModel="true"
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<action id="NextDefaultValues" IterBinding="DefaultValuesIterator"
DataControl="AppModuleDataControl" RequiresUpdateModel="true"
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<methodAction RequiresUpdateModel="true" Action="999"
id="advancedSearchDefaultValues"
IterBinding="DefaultValuesIterator"
DataControl="AppModuleDataControl"
InstanceName="AppModuleDataControl.dataProvider"
MethodName="advancedSearch"
ReturnName="AppModuleDataControl.methodResults.AppModuleDataControl_dataProvider_advancedSearch_result"
IsViewObjectMethod="false">
<NamedData NDName="viewObjectUsage"
NDValue="#{searchDefaultValues.dataCollection}"
NDType="java.lang.String"/>
<NamedData NDName="arguments" NDValue="#{searchDefaultValues.arguments}"
NDType="java.util.ArrayList"/>
<NamedData NDName="allConditionsMet"
NDValue="#{searchDefaultValues.allConditionsMet}"
NDType="java.lang.Boolean"/>
</methodAction>
<action id="setCurrentRowWithKeyDefaultValues"
IterBinding="DefaultValuesIterator"
InstanceName="AppModuleDataControl.DefaultValues1"
DataControl="AppModuleDataControl" RequiresUpdateModel="false"
Action="96">
<NamedData NDName="rowKeyStr" NDValue="#{row.rowKeyStr}"
NDType="java.lang.String"/>
</action>
<action id="CreateDefaultValues" IterBinding="DefaultValuesIterator"
DataControl="AppModuleDataControl" RequiresUpdateModel="true"
Action="40"/>
<action id="DeleteDefaultValues" IterBinding="DefaultValuesIterator"
DataControl="AppModuleDataControl" RequiresUpdateModel="false"
Action="30"/>
<action id="Commit" RequiresUpdateModel="true" Action="100"
DataControl="AppModuleDataControl"/>
<action id="Rollback" RequiresUpdateModel="false" Action="101"
DataControl="AppModuleDataControl"/>
</bindings>
</pageDefinition>
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Toine

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Hi,
I tried to avoid putting in specific code as my question was more on design, and I wanted to save people having to trawl through specific code. And if I had any school assignments outstanding they would be about 20 years too late :-). I'm not sure computers more sophisticated than an abacus were around then...
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Cheers,
Alan
Here's Sessiondemo.class
import java.io.*;
import java.awt.event.*;
import java.util.*;
import java.beans.*;
public class Sessiondemo implements PropertyChangeListener {
    private LoginGUIdemo lgui;   // Login screen
    private int localeIndex; // index referring to an array of available Locales
    public Sessiondemo () {
        lgui = new LoginGUIdemo();
        lgui.addPropertyChangeListener(this);
        lgui.show();
    public static void main(String[] args) {
        Sessiondemo sess = new Sessiondemo();
    public void propertyChange(java.beans.PropertyChangeEvent pce) {
        // Get the userAction value from LoginGUI
        String userAction = pce.getNewValue().toString();
        if (userAction == "Cancelled") {
            System.out.println(userAction);
            // close the screen down
            lgui.dispose();
            System.exit(0);
        } else if (userAction == "LocaleChange") {
            System.out.println(userAction);
            // Get the new locale setting from the LoginGUI
            // ...modify LoginGUI labels with new labels from ResourceBundle
lgui.show();
} else if (userAction == "Submitted") {
System.out.println(userAction);
// ...Get the userid and password values from LoginGUIdemo
            // run some business logic to decide whether to show the login screen again
            // or accept the login and present the application frontscreen
}And here's LoginGUIdemo.class
* LoginGUIdemox.java
* Created on 29 November 2002, 18:59
* @author administrator
import java.beans.*;
public class LoginGUIdemo extends javax.swing.JFrame {
    private String userAction;
    private PropertyChangeSupport pcs;
    /** Creates new form LoginGUIdemox */
    // Note that in the full code there are setters and getters to allow access to the
    // components in the screen. For clarity they are not included here
    public LoginGUIdemo() {
        pcs = new PropertyChangeSupport(this);
        userAction = "";
        initComponents();
    public void setUserAction(String s) {
        userAction = s;
        pcs.firePropertyChange("userAction",null,userAction);
    public void addPropertyChangeListener(PropertyChangeListener l) {
        pcs.addPropertyChangeListener(l);
    public void removePropertyChangeListener(PropertyChangeListener l) {
        pcs.removePropertyChangeListener(l);
    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
    private void initComponents() {
        jTextField1 = new javax.swing.JTextField();
        jTextField2 = new javax.swing.JTextField();
        jComboBox1 = new javax.swing.JComboBox();
        jButton1 = new javax.swing.JButton();
        jButton2 = new javax.swing.JButton();
        getContentPane().setLayout(new java.awt.FlowLayout());
        addWindowListener(new java.awt.event.WindowAdapter() {
            public void windowClosing(java.awt.event.WindowEvent evt) {
                exitForm(evt);
        jTextField1.setText("userid");
        jTextField1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                EnterActionPerformed(evt);
        getContentPane().add(jTextField1);
        jTextField2.setText("password");
        jTextField2.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                EnterActionPerformed(evt);
        getContentPane().add(jTextField2);
        jComboBox1.setToolTipText("Select Locale");
        jComboBox1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                LocaleActionPerformed(evt);
        getContentPane().add(jComboBox1);
        jButton1.setText("Enter");
        jButton1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                EnterActionPerformed(evt);
        getContentPane().add(jButton1);
        jButton2.setText("Cancel");
        jButton2.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                CancelActionPerformed(evt);
        getContentPane().add(jButton2);
        pack();
    private void LocaleActionPerformed(java.awt.event.ActionEvent evt) {
        setUserAction("LocaleChange");
    private void CancelActionPerformed(java.awt.event.ActionEvent evt) {
        setUserAction("Cancelled");
    private void EnterActionPerformed(java.awt.event.ActionEvent evt) {
        setUserAction("Submitted");
    /** Exit the Application */
    private void exitForm(java.awt.event.WindowEvent evt) {
        System.exit(0);
     * @param args the command line arguments
    public static void main(String args[]) {
        new LoginGUIdemo().show();
    // Variables declaration - do not modify
    private javax.swing.JTextField jTextField2;
    private javax.swing.JTextField jTextField1;
    private javax.swing.JComboBox jComboBox1;
    private javax.swing.JButton jButton2;
    private javax.swing.JButton jButton1;
    // End of variables declaration

Best way to remove duplicates based on multiple tables

Hi,
I have a mechanism which loads flat files into multiple tables (can be up to 6 different tables) using external tables.
Whenever a new file arrives, I need to insert duplicate rows to a side table, but the duplicate rows are to be searched in all 6 tables according to a given set of columns which exist in all of them.
In the SQL Server Version of the same mechanism (which i'm migrating to Oracle) it uses an additional "UNIQUE" table with only 2 columns(Checksum1, Checksum2) which hold the checksum values of 2 different sets of columns per inserted record. when a new file arrives it computes these 2 checksums for every record and look it up in the unique table to avoid searching all the different tables.
We know that working with checksums is not bulletproof but with those sets of fields it seems to work.
My questions are:
should I use the same checksums mechanism? if so, should I use the owa_opt_lock.checksum function to calculate the checksums?
Or should I look for duplicates in all tables one after the other (indexing some of the columns we check for duplicates with)?
Note:
These tables are partitioned with day partitions and can be very large.
Any advice would be welcome.
Thanks.

>
I need to keep duplicate rows in a side table and not load them into table1...table6
>
Does that mean that you don't want ANY row if it has a duplicate on your 6 columns?
Let's say I have six records that have identical values for your 6 columns. One record meets the condition for table1, one for table2 and so on.
Do you want to keep one of these records and put the other 5 in the side table? If so, which one should be kept?
Or do you want all 6 records put in the side table?
You could delete the duplicates from the temp table as the first step. Or better
1. add a new column WHICH_TABLE NUMBER to the temp table
2. update the new column to -1 for records that are dups.
3. update the new column (might be done with one query) to set the table number based on the conditions for each table
4. INSERT INTO TABLE1 SELECT * FROM TEMP_TABLE WHERE WHICH_TABLE = 1
INSERT INTO TABLE6 SELECT * FROM TEMP_TABLE WHERE WHICH_TABLE = 6
When you are done the WHICH_TABLE will be flagged with
1. NULL if a record was not a DUP but was not inserted into any of your tables - possible error record to examine
2. -1 if a record was a DUP
3. 1 - if the record went to table 1 (2 for table 2 and so on)
This 'flag and then select' approach is more performant than deleting records after each select. Especially if the flagging can be done in one pass (full table scan).
See this other thread (or many, many others on the net) from today for how to find and remove duplicates
Best way of removing duplicates

Best way to import data to multiple tables in oracle d.b from sql server

HI All am newbie to Oracle,
What is the Best way to import data to multiple tables in Oracle Data base from sql server?
1)linked server?
2)ssis ?
If possible share me the query to done this task using Linked server?
Regards,
KoteRavindra.

check:
http://www.mssqltips.com/sqlservertip/2011/export-sql-server-data-to-oracle-using-ssis/
      koteravindra
Handle:      koteravindra
Status Level:      Newbie
Registered:      Jan 9, 2013
Total Posts:      4
Total Questions:      3 (3 unresolved)
why so many unresolved questions? Remember to close your threads marking them as answered.

Best way to deal with Mutating table exception with Row Level Triggers

Hello,
It seems to be that the best way to deal with Mutating Table exception(s) is to have to put all the trigger code in a package & use it in conjunction with a Statement level trigger .
This sounds quite cumbersome to me . I wonder is there any alternative to dealing with Mutating table exceptions ?
With Regards

AskTom has a good article about this,
http://asktom.oracle.com/tkyte/Mutate/index.html

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