ERD

How to Create a Chen Entity-Relationship Diagram

This tutorial guides you through creating a Chen Entity-Relationship Diagram (ERD) for a simple Content Management System (CMS) using Software Ideas Modeler. You will learn not only the mechanics of drawing the ERD but also the theoretical underpinnings of using entities like weak entities, weak relationships, derived attributes, and more.

Transform SQL Script into ER Diagram, Modify, and Generate Back to SQL

Transforming SQL scripts into Entity-Relationship (ER) diagrams and vice versa is a critical task for database designers and developers. This guide provides a step-by-step approach to converting SQL DDL scripts into ER diagrams, modifying these diagrams, and then generating updated SQL scripts using Software Ideas Modeler. By the end of this tutorial, you'll be well-equipped to visualize, adjust, and apply database designs with ease and precision.

Adjusting Relationship Routing in Entity-Relationship Diagrams

This tutorial will guide you through the process of adjusting the relationships in your ERD for better clarity and organization, specifically focusing on rerouting relationships for a cleaner diagram layout.

Creating and Managing Lookup Tables in ER Diagrams

This tutorial provides a comprehensive guide on creating and managing lookup tables in our powerful tool for database diagramming. This guide will walk you through the process of enhancing an example database schema by adding and configuring a new lookup entity, ensuring effective data management and visualization within your diagrams.

Converting Conceptual Data Types to Database Specific Types

Converting conceptual data types to specific database types in Software Ideas Modeler is a straightforward process that significantly enhances the technical accuracy of your data models.

How to Create an Entity-Relationship Diagram

This straightforward tutorial takes you through the process of designing an Entity-Relationship Diagram (ERD) using Software Ideas Modeler. Focused on building a real-world example relevant to an educational system, this guide covers the creation of key entities such as 'Student', 'Teacher', 'Class', 'Enrollment', and 'Department'. Each step, from adding entities and attributes to establishing various relationships, is explained in a clear, easy-to-follow manner.

Add All Relationships By Model

In complex modeling, maintaining accuracy and efficiency is key. Software Ideas Modeler offers a robust feature Add All Relationships By Model, which automates the process of adding relationships to your diagrams. This tutorial will guide you through using this feature, especially useful when working with models that span multiple diagrams.

Generating Example Data for ERD Entities

Software Ideas Modeler offers a nifty feature to automatically generate example data for Entity Relationship Diagram (ERD) entities. This is especially useful when you need placeholder data for presentations, testing, or early-stage development. The generated data respects the entity's defined attributes and their respective types, making the data realistic and applicable.

Convert Chen ER Diagram to Crow's Foot 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 Parsing

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.

How to Generate SQL DDL Change Scripts

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.

Documentation Generator

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

Composite Key (Entity-Relationship Diagram)

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

One to One Relationship (Entity-Relationship Diagram)

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

Optional Attribute (Entity-Relationship Diagram)

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

One to Many Relationship (Entity-Relationship Diagram)

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.

Foreign Key (Entity Relationship Diagram)

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

Primary Key (Entity Relationship Diagram)

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

Entity-Relationship Diagram Arrow Types

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.

Reverse Engineering Source Code to Model and Diagrams

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.

Convert UML Class Diagram to ERD

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 ER Diagram - Entity-Relationship Diagram in Chen Notation

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.

Generate SQL from ERD

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.

Create ERD from SQL Script

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.

How to Design Database - Designing a Database Schema

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.

Inner, Left, Right and Full Outer Join of Two Entities (Tables)

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.

Change Type Set for Entity-Relationship Diagram

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.

Set Primary Key to ERD Entity (ER Diagram Editing)

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.

Highlighting Relationships in Entity-Relationship Diagrams

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.

Turn SQL Script to Diagram

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