ERD

This tutorial will guide you on how to convert a Chen Entity Relationship Diagram (ERD) to a Crow's Foot ERD using Software Ideas Modeler. One of the key features of this process is that the original Chen ER Diagram is preserved and a new diagram in Crow's Foot notation is created. The Crow's Foot notation allows you to add more detailed information to your ER diagram, such as attribute types, which is not possible with the Chen notation.

SQL DDL scripts can be parsed and turned into ERD or UML class diagrams. The feature can be accessed quickly from the Parser sidebar or the Source Code Import dialog.

Changes made in the data model can be transformed into the SQL DDL scripts. Software Ideas Modeler allows you to generate ALTER and DROP scripts for your changes in the data entities.

Software Ideas Modeler helps you with your project documentation. You can generate documentation for your software or data models.

A composite key is a type of key that consists of two or more attributes.

The relationships in data models can be represented by various types of associations depending on which cardinality is required.

The ERD entity consists of required and optional attributes. An optional attribute do not need any value assigned.

A relationship with one-to-many cardinality represents a link between two entities A and B, where one instance of the A entity refers to many instances of the B entity.

A foreign key specifies a link to another table via an attribute or a set of attributes.

A primary key uniquely specifies a row of data specified by the entity.

The entity-relationship diagram offers only one connector element - relationship, but it can be depicted with various combinations of caps on the ends depending on its cardinality.

The Reverse Engineering tool helps you create new diagrams for the projects with existing source codes in no time. You can select the projects, folders, or files to generate UML class diagrams, package diagrams, and entity-relation diagrams. The tool allows you to create new diagrams or updated diagrams that were already created by a source code.

UML class diagram and ER diagram share the ability to define a domain model. Software Ideas Modeler allows you to convert the classes to entities, associations to relationships and the class attributes to ERD attributes.

Chen's notation of the entity-relationship diagram depicts data and domain models using entities, attributes, and relationships. Unlike other ER diagram notations, it shows attributes as standalone boxes, not as a part of entities.

The entity-relationship diagram can be turned into a SQL script. The ERD tool can generate create scripts for each entity and relationship in the diagram or only for the selected part. You can transform ERD entities into database tables very easily.

The ERD tool allows you to generate an ER diagram from a SQL database. It is also possible to create an ERD from a SQL DDL script. You can turn the whole schema into a diagram or you can select only some tables that you want to be imported.

If you want to design a data model for your database, you should use an entity-relationship diagram (also known by ERD acronym). It may be used for conceptual, logical, and also physical data models. Alternatively, you may also use a UML class diagram for the same purpose.

There are multiple options on how to join rows of two entities into a single result set. It depends on whether you want to have all data from the left entity or right entity, both entities, or you would like to get the data that are present in both entities.

The type set is set to UML by default. When creating data models using E-R diagrams you may want to use another type set - e.g. database-specific.

A primary key uniquely identifies a tuple/row of entity (data set, table). It may be an attribute or a set of attributes. Primary key attributes are marked with + symbol, alternatively with PK acronym or a key icon.

The ERD tool provides many useful features to help you work with diagrams. One of them is the highlighting of the context parts in the diagram.

Using Smart Parser sidebar, you may easily convert SQL scripts to entity relationship diagrams.