An entity structure chart is a visual representation of everything related to the entities related to the business rules, activities as well as the data model for the company in its database, data warehouse or any general information system implementation.  It is a chart that depicts the structure and existence of data attributes and data entities in the common data structure.

An entity structure chart draws the graphical structure for any data within the enterprise common data structure. This graphical drawing is intended to help data document analysts, database administrators, informational technology and all other staff of the organization visualized the data structures and the information system design.   Entity relation diagrams makes use of  Entity Structure Chart in order to provide a complete representation of the logical data structure.

Without the aid of an entity structure chart, data entities and all attributes and relations pertaining to them, would all be defined in bullet format with details in paragraph format. This can be straining to the eyes as well as difficult to analyze because one will have to dig through all those words and sentences.

With an entity structure chart, it becomes easy to have an analysis that shows the position of any selected entity in the structures that have been defined. An entity may exist in many structure charts. This chart would also give a great benefit in validating the position or absence of an entity within one or more specific structures.

For instance, there might be a need for identifying where a specific set of departmental data exists within the structure of the entire organization. With an entity structure, it would be very easy to spot and point to the location of the departmental data being looked for.

The data entities which are represented in the entity structure chart may include resource data, roles of the entity, data from each organizational or departmental unit, data location, and any other business items which may apply.

An entity represents any real world object and the entity structure is technically and basically the formalism used in a structural knowledge representation scheme that systematically organizes a family of possible structures of a system. Such an entity structure chart illustrates decomposition, coupling, and taxonomic relationships among entities.

The decomposition of an entity is the particular area which is concerned with how the any entity may be broken down further into sub-entities until its atomicity. Coupling pertains to the specifications detailing how sub-entities may be coupled together to reconstitute the entity.

An entity structure chart has a direct support for the entity relation diagram. This diagram is the visual and graphical representation of all of the interrelationships between entities and attributes in the database. And while the entity relation diagram uses graphical symbols such as box, diamond, oval and lines for representing the entities and relationships in the database, the entity structure chart may or may not use the same symbols in trying to visualize the structure of the entity for the database or the enterprise information system.

It could be said that an entity structure chart is the break down of the components of the entity relations diagram. In the entity relations diagram only the entities and the table relations are being specified. But for the entity structure chart, the visual illustration may include a symbol for the entity is structurally represented.

For instance, let us say the entity is a CUSTOMER. The entity structure details everything about the customer including name, age, etc, and its relationships with products and other entities and at the same time the data type on how the CUSTOMER and its attributes will be physically stored in the database.