The system modeling tools are used to do a large portion of the analysis work in the life cycle of an Oracle project. The tools discussed in this chapter—the Entity Relationship Diagrammer, the Functional Hierarchy Diagrammer, and the Dataflow Diagrammer—all have a very similar screen format. On the top is a pull-down menu as well as a toolbar of icons. All of the functions that these icons perform can also be found on the menu bar under Edit, View, Utilities, and Tools. Whether the user wants to use the icons or the menu is a matter of style. For the most part, the descriptions in this chapter use the icons rather than the menu bar.

Initially you may create a new diagram either by choosing New from the File menu or by hitting the New Diagram icon. When you choose this icon or any icon from the Designer 2000 toolset, help is always available. The help message appears in a balloon to the right of the icon when you move your cursor next to the icon and do not depress it. You can also get help by selecting anything on your diagram (whether an icon or an element) and pressing the question mark icon. Finally, you can search for help on any topic from the help menu selection.

Entity Relationship Diagrammer

This section provides a brief overview as to how to model information using the Entity Relationship Diagrammer. Entities, or things of significance in your system, can be shown graphically with this tool. Using this method, you can also show the relationships between entities.

Starting Up

You start the Entity Relationship Diagrammer by clicking on its icon and entering your user ID, password, and application. Across the top of the screen, you will see a set of icons used for designing a diagram, as shown in Figure 26.1.

Figure 26.1. The Entity Relationship Diagrammer.

Creating a Diagram

To create any Entity Relationship Diagram you must follow certain steps. You will need to include summary information, add entities and relationships, and save the diagram in the database.

Summary Information

Initially when your diagram is started, you may want to fill in the summary information so that you can easily identify the diagram when it is printed. Under the File menu is a choice called Summary Information. A window pops up showing you all the choices for information to be included on your chart. See Figure 26.2.

Figure 26.2. The Entity Relationship Diagram Summary Information.

Select any information you want to display on the diagram. If you want to include your name or a diagram title, you need to fill in these items.

Adding the Entities

You are now ready to start adding information or entities to your diagram. You may have already created your entities in RON—the Repository Object Navigator—or some may have been entered by another user in RON or on another diagram. You can also create them right here in the Entity Relationship Diagrammer. If you need to create entities, select the Entity icon (refer to Figure 26.1). After you depress the icon, drag your cursor onto the diagram page. After you select a spot for the entity, you will be prompted for a name, short name, and plural for your entity. Then the entity is created. You can edit the entity by double-clicking on its shape. You can add attributes, unique keys, synonyms, and any descriptive text at this point. As long as you make the size of your entity sufficiently large on the screen, all of the attributes will be displayed. Otherwise, a set of dots signifies that more information is available about the entity. You may increase or decrease the size of the entity by selecting it and dragging it from one of its bold-faced points. After you create an entity on your diagram, the entity and any information you add or edit on it is added to RON.

If you want to create more than one entity without having to select the button each time, hold down the Shift key when you select the entity button. When you are ready to move to another activity, press another button on the icon bar.

You can also select entities from RON. From the Menu bar choose Edit | Include | Entities. A list of available entities will appear. After you select an entity, the diagrammer automatically puts on the diagram the entity as well as any relationships it already has to any other entities on the diagram. You can bring in an entity with or without its relationships. To bring it in with relationships, select the With Relationships box before hitting the OK button.

To select multiple entities from the include list, hold down the Ctrl key and click on the entities you require or select a block of entities by holding down the Shift key. If you choose a large number, your diagram may become too difficult to follow for the initial editing, so keep this in mind when you make your selection.

Editing Attributes

You can add a great deal of information about attributes in the Entities properties screen. Just double-click on the entity and go to the Attributes Detail tab. Here you can add field type, length, a comment (which is the basis for the database comment and hint), length, and nullability. Go to the Attribute Values tab, and you can add allowable values or an allowable range for an attribute.

Creating Subtypes and Supertypes

You may want to divide your entity into subtypes. To add a subtype inside an entity, just create an entity and place your cursor inside the supertype when you place it on the diagram. You can also create subtypes and supertypes by dragging existing entities into the existing entity that will be the supertype.

Adding Relationships

After you have multiple entities on your diagram, you may want to show their relationships to one another. To do so, select one of the Relationship icons (refer to Figure 26.1). Select the relationship for which you are looking. Then select the From entity. Next select the To entity. When they are both selected, the system prompts you for the two relationship names. Then it places the relationship lines and the names on the diagram.

If you want to create more than one relationship without having to select the button each time, hold down the Shift key when you select the relationship button. When you are ready to move on to another activity, press another button on the icon bar.

If you set the property of including entities not to include relationships, you can include relationships from RON. To do so choose Edit | Include | Relationships off the menu bar. Choose the relationship you want to include from the list, and it will appear on the diagram.

To select multiple relationships from the list, hold down the Ctrl key and click on the relationships you require, or select a block of relationships by holding down the Shift key. If you choose a large number, your diagram may become too difficult to follow for the initial editing, so keep this in mind when you make your selection.

Sometimes you may want to show an arc across multiple relationships. First select each relationship in the arc by selecting one and then holding down the Ctrl key while selecting the others. The Create Arc icon becomes active (refer to Figure 26.1). Click on the Create Arc icon, and the arc will appear. To remove a relationship from an arc, click on the arc and then hold down the Ctrl key while selecting the relationships to remove. Then the Remove from Arc icon becomes active. Click on the Remove from Arc icon, and the relationships will be removed from the arc. If you want to add a relationship to the arc, click on the relationship to add and hold down the Ctrl key while selecting the relationships to add. Then the Add to Arc icon will become active. Click on the Add to Arc icon and the relationships will be added to the arc.

Using Domains

To create a domain, use Edit | Domain from the menu bar. You will find a window where you can define the attributes and allowable values of the domain. A domain cannot be depicted on an Entity Relationship Diagram as an entity, only as an attribute of an entity. In the attribute definition, the attribute can be linked to a domain.

For depiction purposes at the analysis level, it makes sense to depict domains as entities without attributes. All of these entities could have a similar title, such as Types. For example, you could use Payroll Type, Employee Type, or Status Type to represent attribute types that will become domains in your physical model.

Saving the Diagram

When you are ready to save the diagram, do so by selecting File | Save from the menu bar. You can also save by clicking the Save icon (refer to Figure 26.1). At this point you can name your diagram.

It is important to save often. The Oracle client/server tools use a large amount of memory and can sometimes cause a general protection fault on the PC. Saving often decreases the risk of losing any unsaved work.

Multiple Diagrams

Often, there are multiple diagrams for one application in CASE. For example, a business may have an accounting department and a payroll department. Both departments could have separate diagrams. A third diagram could depict all of the departments in the business.

Consolidating

When you make changes to an entity or its relationships, the changes can be made in either the Entity Relationship Diagrammer or RON. The changes will not be reflected on other diagrams that use the same entities. There may be a reason for the user to keep the changes off—the changes may reflect an earlier point in time, or they may reflect the business opinions of another department. However, it is possible to take into account changes from other users and consolidate them into the current diagram. To do so, you must choose Edit | Consolidate from the menu bar. At this point you can choose whether to consolidate a specific entity, relationship, or the entire diagram.

If you do not consolidate an element that has changed, you cannot edit it.

Making a Diagram Easier to Follow

In several ways you can make the diagram easier for the customer to follow.

Autolayout

As you add entities to the diagram, you will place them where they seem to fit, and the layout may become crowded. When an existing entity is chosen from Include, the entities may be placed on the diagram in a haphazard manner. If the diagram starts to look ugly, use the Autolayout icon (refer to Figure 26.1). When the icon is clicked, the entities and relationships are shifted around for readability. If you don't like the way the computer resets the layout, you can press the Autolayout icon again. You can continue to press the icon until you are happy with the outcome. You can go back to the last prior autolayout by using the Revert Layout icon.

Autolayout for a Specific Area

Sometimes you will add a number of new entities to a specific area, and the layout of these entities will become difficult to follow. To reposition these entities, you need to select just these entities and press the Autolayout button. To reposition these entities to another area on the diagram, select these entities and choose Utilities | Autolayout to new area from the menu bar. Select where you want to reposition the entities and drag an area large enough to fit the entities. When you release the mouse, the entities will be repositioned in the new area.

Using Colors, Fonts, and Line Width

It is also possible to change the colors of entities and relationships, the fonts of words, and the line width of entity outlines and relationships. By changing these items, you can make the diagram more readable and add intelligibility. For example, all Type entities (the ones which may represent domains) can be filled in with blue.

The colors on the diagram show up only if you have a color printer. If you are using a black-and-white printer, however, colors show up as different shades of gray, so one color differentiation can be used.

You can change all of the diagram or just a specific entity, relationship, or combination. To change the entire diagram, choose Edit | Select all from the menu bar. To select one or more entities or relationships, select one and hold down the Ctrl key until all the items are selected.

To change the line width, select the Line Width icon (refer to Figure 26.1). Choose a line width from the items listed. To change the line color, choose the Line Color icon. Choose a line color from the colors listed. To change the fill color of entities, choose the Fill Color icon. Choose a color from the items listed. To change the font of any text selected, choose the Text icon. The font, the font style, and the size of text all can be changed.

Working with Large Diagrams

When you work with large diagrams, you may find it difficult to keep track of where you are on the diagram. Also, the diagram can consume many pages when they are printed. There are simple ways to deal with these irritations.

Using Navigate

From Edit | Navigate on the menu bar, select either an entity or a relationship. The cursor selects the item requested, and the focus of the screen includes the item requested.

Minimizing the Number of Pages

Often, when the diagram is filled with many entities, it becomes very large, sprawling horizontally or vertically. As a result, many blank pages may fill the borders of the diagram. You can reposition the diagram to use the fewest number of pages by using the Minimize Number Of Pages icon. Pressing this icon repositions the entire diagram so that it uses the least number of pages.

Zooming In and Out

You can zoom in and out of your picture to see how an area or the entire picture looks. The Magnifying Glass icons enable you to perform this function. Use the Normal Size icon (refer to Figure 26.1) to return to regular screen size. Use the Enlarge icon to enlarge the view. Use the Shrink icon to shrink the view.

Functional Hierarchy Diagrammer

This section provides a brief overview of how to model information using the Functional Hierarchy Diagrammer. Functions, or activities in your system, can be shown graphically with this tool. Using this method, you can also show the relationships or hierarchy among functions.

Starting Up

Start the Functional Hierarchy Diagrammer by clicking on its icon and entering your user ID, password, and application. Across the top of the screen, you will see a set of icons used for designing a diagram, as shown in Figure 26.3.

Figure 26.3. The Functional Hierarchy Diagrammer.

Creating a Diagram

To create any Functional Hierarchy Diagram, you must follow certain steps. You should include functions, lay out the hierarchy, and save the diagram in the database.

Adding Functions to a Diagram

You can create functions on the diagram or bring them in from RON—the Repository Object Navigator. To create a function on the diagram, select the Function icon (refer to Figure 26.3). After selecting the icon, click on a place on the diagram where the function should be placed. The system will prompt you for a short name and title for the function.

If you want to create more than one function without having to select the button each time, hold down the Shift key when you select the function button. When you are ready to move on to another activity, press another button on the icon bar.

The short name of the function can contain information about the function—such as ACCOUNT for "Keep track of user accounts"—or it can represent the functional breakdown of the function within the hierarchy, such as REP for all reports, and REP01, REP02, and REP03 for each report.

In the Repository Reports, the Function Definition Report has an option for listing all functions on a diagram. Currently, this option does not work unless you give all functions a short name that starts with the same alphanumeric string. Make sure no function outside this diagram starts with this string. You can ask for the report by functions that start with the string.

The short name of a function is the default for the short name of a module, which is the default for the name of a Windows file. Therefore the name should be limited to eight characters to conform to Windows standards.

After you add the function, you can include other information about the function just by double-clicking on the function box. The edit function window pops up where you can edit the definition of the function, any notes to be added, the frequency of use, the entities used by the function, the attributes, the CRUD (Create, Retrieve Update, Delete usage) and triggers.

To enter or edit entities and attributes, select an entity from the list. Then select an attribute or set of attributes by holding down the Ctrl key. Next, click the down arrow to insert your choice onto the dataflow list. To remove them from the dataflow list, click the up arrow. Data items are manually entered.

In the trigger area, you can specify any functions that are triggered by completion of the current function. For example, the function of printing payroll checks may trigger the function of distributing payroll checks.

A function can also be created as a child of another function. After you press the Function icon, select the parent function from the diagram. Then continue as you normally would in creating the function. The function will now be displayed as a child.

All of the characteristics of a function are editable. However, if you edit the short name of a function and it is the parent of another function, when you print out the function definition, the old name of the parent function will appear on the definition of the child. This error occurs because the CASE system has denormalized the function definition table and the original parent name is stored with the child. If you run into this problem, contact Oracle Support and they will supply you with a utility to solve this problem.

You can also include a function from the RON. Using Edit | Include | Function from the menu bar, choose the function from the available list.

To select multiple functions from the list, hold down the Ctrl key and click on the functions you require, or select a block of functions by holding down the Shift key. If you choose a large number, your diagram may become too difficult to follow for the initial editing, so keep this in mind when you make your selection.

Changing Diagram Layout

There are three types of diagram layout:

Vertical—all functions are displayed vertically on the diagram (see Figure 26.4).

Horizontal—all functions are displayed horizontally, with each level displaying vertically (see Figure 26.5).

Hybrid—a combination of Vertical and Horizontal that seems the most appealing based on the functional breakdown (see Figure 26.6).

To choose a specific layout type, select Tools from the menu bar. Choose Vertical, Horizontal, or Hybrid from the layout choices.

Figure 26.4. A vertical layout for a functional hierarchy.

Figure 26.5. A horizontal layout for a functional hierarchy.

Figure 26.6. A hybrid layout for a functional hierarchy.

Resequencing Functions

After you have created your diagram, you may want to resequence certain functions. To do so, click on the Resequence icon (refer to Figure 26.3). Then select the function you wish to resequence. Drag it just beyond the function you want it to follow. Then release the button.

When you make a function the last function, there is no room on the function hierarchy for it at the end. Instead, make it the second-to-last function. Then move the last function in front of it.

Moving a Function to a New Parent

Sometimes it makes sense to move a function from one area of the diagram to another. To reparent a function, click on the Reparent icon (refer to Figure 26.3). Then select the function you wish to reparent. Drag the cursor to the new parent and release the button.

Sharing Functions

Sometimes a function is used more than once in an application, or a function is used in multiple applications. Rather than make a function redundant, you can refer to it multiple times or make it into a shared function. Double-click on the function that will be a copy of another function. In the common area, enter the application and the short name of the function you are copying.

Designer/2000 enables you to enter any information on a referencing function that you would on a regular function such as notes, description, entity usage, and so on. However, when you are printing a function definition for a function that references another function, the only data that is displayed is the data from the common function, not any extra notes you may have added to the function referencing the information.

Saving the Diagram

When you are ready to save the diagram, do so by selecting File | Save from the menu bar. You can also save by clicking the Save icon (see Figure 26.3). At this point you can name your diagram.

It is important to save often. The Oracle client/server tools use a large amount of memory and can cause a general protection fault on the PC. Saving often decreases the risk of losing any unsaved work.

Consolidating

When you make changes to a function's definition or its point in the hierarchy, you can enter the changes in either the Diagrammer or RON. The changes are reflected on other diagrams that use the same functions. There may be a reason for you to keep the changes off—they may reflect an earlier time or the business opinions of another department. However, it is possible to take into account the changes from other users and consolidate them into the current diagram. To do so, you must choose Edit | Consolidate from the menu bar. At this point you can choose whether to consolidate a specific function or the entire diagram.

If you do not consolidate an element that has changed, you cannot edit it.

Making Diagrams Easier to Follow

When you work with large diagrams, it can become difficult to keep track of where you are on the diagram, and the diagram can consume many pages when printing. There are simple ways to deal with these irritations.

Minimizing the Number of Pages

Often, when the diagram is filled with many functions, it becomes very large, sprawling horizontally or vertically. As a result, many blank pages may fill the borders of the diagram. The diagram can be repositioned to use the fewest number of pages by using the Minimize Number Of Pages icon. Pressing this icon will reposition the entire diagram so that the least number of pages are used.

Using Colors, Fonts, and Line Width

It is also possible to change the colors of functions and the hierarchy lines, the fonts of words, and the line width of function outlines and hierarchy lines. By changing these items, you can make the diagram more readable and intelligible. For example, all payroll functions could be filled in with green.

The colors on the diagram will only show up if you have a color printer. If you are using a black-and-white printer, colors will show up as gray, so one color differentiation can be used between gray and black.

You can change all of the diagram or just a specific function, hierarchy line, or a combination. To change the entire diagram, choose Edit | Select all from the menu bar. To select one or more function or hierarchy line, pick one and hold down the Ctrl key until all the items are selected.

To change the line width, select the Line Width icon (refer to Figure 26.3. Choose a line width from the items listed. To change the line color, choose the Line Color icon. Choose a line color from the line colors listed. To change the fill color of entities, choose the Fill Color icon. Choose a color from the items listed. To change the font of any text selected choose the Text icon. The font, font style, and size of text can all be changed.

Zooming In and Out

You can zoom in and out of your picture to see how an area or the entire picture looks. The magnifying glass icons enable you to perform this function. Use the Normal Size icon (refer to Figure 26.3) to return to normal size. Use the Enlarge icon to enlarge the view. Use the Shrink icon to shrink the view.

Dataflow Diagrammer

This section provides a brief overview of how to model information using the Dataflow Diagrammer. Dataflows between functions and the world outside the business model. The Dataflow Diagrammer is used to show when the data is brought into the system, what format it is in, and where it ends up in the model being designed.

Starting Up

Start the Dataflow Diagrammer by clicking on its icon and entering your user ID, password, and application. Across the top of the screen, you will see a set of icons used for designing a diagram (see Figure 26.7).

Figure 26.7. The Dataflow Diagrammer.

Creating a Diagram

To create any Dataflow Diagram, you must follow certain steps. You should include functions, define dataflows, datastores, and external storage, and you must save the diagram.

Using Functions

A dataflow diagram must contain functions, so you should create a functional hierarchy prior to using the tool in either RON or the Function Hierarchy Diagrammer. If you discover while using the Dataflow Diagrammer that you forgot a function, you can add it directly in the Dataflow Diagrammer. Press the Function icon (refer to Figure 26.7). You will be prompted for a short name and a description (similar to using the Function Hierarchy Diagrammer). If you need to create an entire hierarchy, it is better to use the Function Hierarchy Diagrammer.

When you create a new diagram, you will be prompted to select a function that will be the base for the diagram, generally a parent function. Next, add the children you want to depict in the diagram. To include an existing function from the application, just use Edit | Include | Function from the menu bar. Then choose where you want to place it on the diagram.

After adding a function, you can edit it. The entities used in this function can be defined, as well as the attributes of the entities within this function. Double-click on the function to edit it.

Adding Datastores

A datastore is a site where data for entities or attributes can be stored for use by a function. For example, a paper timecard is temporarily the datastore for an employee's hours until the hours are entered into the system. The datastore can be added by clicking the Datastore icon (refer to Figure 26.7). After you decide where you want the datastore on the diagram, you can add the short name and description for the datastore. If a datastore is used when performing a function, place it inside the function.

After adding the datastore, you can edit it. The entities in the datastore can be defined, as well as the attributes of the entities. Double-click on the datastore to edit it. From there you can edit the description, any notes on the datastore, and the entities, their attributes, and other data elements. Select an entity from the list. Then select an attribute or set of attributes by holding down the Ctrl key. Next, press the down arrow to insert them onto the dataflow list. To remove them from the dataflow list, hit the up arrow. Data items are just manually entered.

You can also include datastores from RON, if you entered them previously on another diagram. To select an existing datastore, select Edit | Include Datastore from the menu. Select an existing datastore from the list.

Adding Externals

Externals are repositories outside of the function where entities, attributes, or data elements are stored. To add externals to the diagram, select the Datastore icon. Place the cursor where you want the external on the diagram. Enter the short name and description.

If you want to create more than one external without having to select the button each time, hold down the Shift key when you select the external button. When you are ready to move on to another activity, press another button on the icon bar.

After you add an external, you can edit it. To do so, double-click on the external. On the screen you can edit the short name, description, information about whether it comes from outside the application (possibly from another application), a comment, and its representation. The representation signifies whether it is an entity or business unit. You can select a specific entity or business unit from the list of values.

You can also include externals from RON, if you entered them previously on another diagram. To select an existing external, select Edit | Include Datastore from the menu. Select an existing external from the list.

Adding Dataflows

Dataflows can be added to signify the flow of data from any one element to another. To create a dataflow, select the Dataflow icon (refer to Figure 26.7). Select the parent element for the flow and then select the child element. Now enter a description for the flow. If no description is entered, the diagrammer will list the word none.

If you want to create more than one dataflow without having to select the button each time, hold down the Shift key when you select the dataflow button. When you are ready to move on to another activity, press another button on the icon bar.

After you add a dataflow, you can edit it by double-clicking on the item. From there you can edit the description, any notes on the dataflow, and the actual data flowing out of the parent element—the entities, their attributes, and other data elements. Select an entity from the list. Then select an attribute or set of attributes by holding down the Ctrl key. Next, hit the down arrow to insert them onto the dataflow list. To remove them from the dataflow list, hit the up arrow. Data items are manually entered.

You can also include dataflows from RON, if you entered them previously on another diagram. To select an existing dataflow, choose Edit | Include Dataflow from the menu. Select an existing dataflow from the list.

Adding Resolved Flows

Resolved flows, or dataflows at levels lower than the functions displayed, can be added to the diagram to display the flow of data below the level of your diagram. To select an existing resolved flow, select Edit | Include Resolved Flow from the menu. Select an existing dataflow from the list.

Saving the Diagram

When you are ready to save the diagram, do so by selecting File | Save from the menu bar. You can also save by depressing the Save icon. At this point, you can name your diagram.

Modifying Dataflow Structure

After a diagram has been developed, you may return to analysis and discover that one dataflow actually represents multiple dataflows. You can then split or divide the dataflow.

You cannot split or divide a resolved flow.

Splitting a Dataflow

Splitting a dataflow creates an interim datastore between the two original elements of a dataflow. To split a dataflow, select the Split Dataflow icon (refer to Figure 26.7). A default name is derived from the name of the dataflow. To edit the new datastore, double-click on the item. You can edit it in the same manner as a datastore.

Dividing a Dataflow

If a dataflow contains multiple attributes or data elements, you may discover that the dataflow actually originates from different sources. To divide the dataflow, click the Divide Dataflow icon (refer to Figure 26.7). This creates an identical dataflow, with the name of the original flow followed by a number 1. Select the elements to be removed from the new dataflow (since they are identical to the original dataflow) with the down arrow. Change the name of the dataflow to a more acceptable one. Once the Dataflow Diagrammer resumes, move the new dataflow to the proper elements.

Multiple Diagrams

Often there will be multiple diagrams for one application in CASE. For example, a business may have an accounting department and a payroll department. Both departments could have separate diagrams. There could be a third diagram that depicts all of the departments in the business.

Consolidating

When you make changes to an entity or its relationships, you can make them in either the Dataflow Diagrammer or RON. The changes will not be reflected on other diagrams that use the same entities. There may be a reason for the user to keep the changes off—they may reflect an earlier time or the business opinions of another department. However, it is possible to utilize changes from other users and consolidate them into the current diagram. To do so, you must choose Edit | Consolidate from the menu bar. At this point, you can choose whether to consolidate a specific entity, relationship, or the entire diagram.

If you do not consolidate an element that has changed, you cannot edit it.

Making a Diagram Easier to Follow

There are several ways you can make the diagram easier for the customer to follow.

Autolayout

When you add entities to the diagram, you will place them where they seem to fit. As you add entities, the layout may become crowded. When an existing function is chosen from Include, the function may be placed on the diagram in a haphazard manner. When the diagram starts to look ugly, it is time to use the Autolayout icon (refer to Figure 26.7). When the icon is clicked, the elements and their dataflows are shifted around for readability. If you don't like the way the computer resets the layout, you can press the autolayout icon again. You can continue to press the icon until you are satisfied with the outcome. To go back to the previous layout, you can click the Revert Layout icon.

Autolayout for a Specific Area

Sometimes when you add a number of new elements to a specific area, the layout of these elements becomes difficult to follow. To reposition these entities, you need to select only these entities and press the Autolayout icon. To reposition these entities to another area on the diagram, select the entities and choose Utilities | Autolayout to new area from the menu bar. Decide where you want to reposition the entities and drag an area large enough to fit the entities. When you release the mouse the entities will be repositioned in the new area.

Using Colors, Fonts, and Line Width

It is also possible to change the colors of functions, dataflows, datastores, and externals, the fonts of words and the line width of element outlines and dataflows. By changing these items, you can make your diagram more readable and add intelligence. For example, all Payroll externals can be filled in with blue.

The colors on the diagram will only show up if you have a color printer. However, if you are using a black and white printer, colors will show up grayed, so one color differentiation can be used.

You can change all of the diagram or a specific element, dataflow or combination. To change the entire diagram choose Edit | Select all from the menu bar. To select one or more elements or dataflows, choose one and hold down the CTRL key until all the items are selected.

To change the line width, select the Line Width icon (refer to Figure 26.7). Choose a line width from the items listed. To change the line color, choose the Line Color icon. Choose a line color from the colors listed. To change the fill color of entities, choose the Fill Color icon. Choose a color from the items listed. To change the font of any text selected, choose the Text icon. The font, font style, and size of text can all be changed.

Working with Large Diagrams

When you work with large diagrams, you may have difficulty keeping track of where you are on the diagram, and the diagram can consume many pages when printing. There are simple ways to deal with these irritations.

Minimizing the Number of Pages

Often a diagram filled with many elements becomes very large, sprawling horizontally or vertically. As a result, many blank pages may fill the borders of the diagram. You can reposition the diagram to use the fewest pages by using the Minimize Number of Pages icon. Clicking this icon will reposition the entire diagram so that fewest pages are used.

Zooming In and Out

You can zoom in and out of your picture to see how an area of the picture or the entire picture looks. The magnifying glass icons enable you to perform this function. Use the Normal Size icon (refer to Figure 26.7) to return to normal size. Use the Enlarge icon to enlarge. Use the Shrink icon to shrink.

Summary

The System Modeling tools are used to do analysis work in the life cycle of an Oracle project. The Entity Relationship Diagrammer creates a diagram of the information stored in the business model. The Functional Hierarchy Diagrammer creates a diagram of the way the information is used in the business model. Once the Entity Relationship Diagram and Functional Hierarchy Diagrams are created, the Dataflow Diagrammer creates a diagram that shows how the information flows in and out of the business functions.