With Astah Professional, you can create ER Diagrams (Entity-Relationship Diagrams) in IDEF1X or IE notations.
Also, you can auto-generate ER diagrams by reversing tables from your database. All models are stored in one place and can be converted to other models like UML Class diagram models and vice versa.
ER Diagram Sample

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Creating ER Diagram

  1. Go to [Diagram] – [ER Diagram] from Main Menu.
    Create ER Diagram

  2. In the tree view, the Domain and ER Diagram will be created under the [ER Model] package.
    ER Diagram on the tree
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Auto-generate ER Diagram

You can generate ER Diagrams after importing database tables with DB Reverse Plug-in.

  1. Right-click on the target ER Model in the Tree and select [Auto Create ER Diagram].
    Auto Create ER Diagram

  2. A diagram will be generated and opened automatically.
    ER Diagram Sample
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Logical and Physical name

Each model has can have both Logical and Physical names.
Physical Name and Logical Name

There are three ways to switch the display of names logical or physical.

1. Right-click on the diagram and select [Diagram Model Type] from its pop-up menu.
Switch logical and physical name

2. Click [Diagram Model Type] in the Structure Tree.
Switch ER Model Notation

3. Switch from ER Diagrams’ Property View (Bottom-left pane).
Switch Logical and Physical name


TIPS – Set default name type

You can set logical or physical name as default in the [Tools] – [System Properties] – [ER Diagram].

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Switch Notations  – [IDEF1X] or [IE]

You can switch the diagram notation between [IDEF1X] and [IE]. There are two ways to switch the notation.

1. Right-click on the ER diagram and click [Diagram Notation] from its pop-up menu.
Switch ERD Notation

2. Switch from ER Diagram’s Property View (bottom-left pane.
Switch ERD Notation

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ER Entity

Creating an ER Entity

You can find out 5 ways to create an ER Entity in the Diagram Editor page.
ER Entity

Add Primary keys and Attributes

There are a few ways to add Primary keys and Attributes to ER Entities.
One is using “Suggest Feature”. When you have a mouse over an ER Entity, a few mini icons will appear. To add a Primary key, click the red button and to add an Attribute, click the orange one.
Add Primary Keys

Once you add one, you can create another by hitting the [Enter] key.
Adding Attributes to ER Entities
Since version 8.5, you are able to add Primary keys and Attributes by pasting text.

Add Attributes by text

Display Level of ER Entities

There are three display levels for ER Entities. Entity, Primary key and Attribute.
ER Entity DIsplay Level

You can change it from ER Entities pop-up menu – [Display Level].
ER-Entity Display Leval Menu

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Add a single ER Domain

You can create ER Domains from pop-up menu of [Domain] in the tree view.
Add ER Domains

Add plural ER Domains

You can also add more than one ER Domain at once.
1. Click [Add ER Domains] in the tree view or go to [Tools] – [ER Diagram] – [Add ER Domains].
Add Multi domains to Astah ER Diagram
2. Specify the domain data in the list.
Add Multiple Domains to ER Diagram

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Add domain to an ER Entity

You can drag a Domain from the Tree to an ER Entity directly on the diagram.
Add Domain to ER Entity

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Select Identifying Relationship, Non-Identifying Relationship or Many-to many Relationships from the Tool palette and click two Entities to connect.



Relationship type

Identifying RelationshipIdentifying RelationshipIdentifying Relationship
Non-Identifying RelationshipNon-Identifying RelationshipNon-Identifying Relationship
Many-to-many RelationshipMany-to-many RelationshipMany-to-many Relationship
  1. Choose which type of relationship you want to create.
    Create a relationship

  2. Click two Entities.
    Create ER Entities

  3. The relationship is now created. Foreign keys would be automatically added depending on the relationship type.
    Create Relationship
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SQL Export

  1. You can export ER Entities into SQL (SQL-92). To export, go to [Tools] – [ER Diagram] – [SQL Export], then select Entities you want to export.

  2. [SQL Export] Dialog opens. Specify the location where you want to export to.

  3. In the [Option], you can specify more detailed settings.
    SQL Export box

TIPS: Export Entity Definition as a comment

You can export the Entity’s definition as a comment by configuring so in the [Option] menu.
SQL Export Option

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ER Data Type

  1. Go to [Tools] – [ER Diagram] – [Set ER Data Type] from main menu.
    ER Data Type

  2. Click [Add] button to add a new ER Data type.
    Add ER Data Type

  3. Enter the new Data Type in this dialogue and click [OK].
    Set ER Data Type

TIPS: Set Default Data Type

You can set the default Data type for an Entity attribute by marking it at [Default Type].
Setting Default ER Data Type

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Export Entity Definition Report

You can export a list of ER Domains, Entities and each Entity’s detailed information to Excel file.

1. Go to [Tools] – [ER Diagram] – [Export Entity Definition Report].
Export ER Table

2. A list of domains, entities and each entity information would be exported.
Export Entity Definition Report

3. Enter the new Data Type in this dialogue and click [OK].
ER Entity in Excel

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Export format of Attributes and its TaggedValues

Logical Name of Attribute$each.entity.each.attribute.logical_name
Physical Name of Attribute$each.entity.each.attribute.physical_name
Domain Name of Attribute$each.entity.each.attribute.domain
Primary Key Flag of Attribute$each.entity.each.attribute.pk
Foreign Key Flag of Attribute$each.entity.each.attribute.fk
NotNull Flag of Attribute$each.entity.each.attribute.notnull
Reference of Attribute$each.entity.each.attribute.ref
Datatype of Attribute$each.entity.each.attribute.type
Length/Precision of Attribute $each.entity.each.attribute.length_precision
Initial Value of Attribute$each.entity.each.attribute.initial_value
TaggedValue of Attribute$each.entity.each.attribute.initial_value