# Entity Properties
In **Data Designer**, users can design an application’s data model by creating entities (tables) either **from scratch** or by **importing them from an existing database schema**.\
Each entity represents a database table and can be fully configured using the **Entity Properties** panel.
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### Create a New Entity
To create a new entity:
1. Select the **Entity** icon from the toolbar
2. Click or drag on the **design panel** to place the entity
Once created, the **Entity Properties** window opens automatically on the right‑hand side.
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### Entity Properties Overview
The Entity Properties panel is organized into multiple sections, each controlling a specific aspect of the entity definition.
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### Entity – General
This section defines the basic metadata of the entity.
* **Name**\
Defines the name of the database table.
* **Comment**\
Adds descriptive information about the table.
* **Color**\
Changes the visual color of the table card in the ER Diagram for better readability.
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### Entity – Columns
This section is used to define the structure of the table columns.
#### Add Columns
* Click the **Add Column** icon to add a new column.
Column Attributes
* **Name** – Column name
* **Type** – Database column data type
* **N (Not Null)** – Enforces NOT NULL constraint
* **PK (Primary Key)** – Marks column as part of the primary key
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#### Extended Column Properties
Expand the column details to configure additional attributes.
Additional properties include:
* **Length** – Maximum length of the column
* **Precision** – Number of digits after the decimal
* **Default Value** – Default column value
* **Auto Increment** – Automatically increment value on insert
* **Delete** – Remove the column from the entity
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### Entity – Indexes & Unique Constraints
This section allows users to define:
* **Indexes**
* **Unique key constraints**
These constraints **do not appear visually in the ER Diagram**, but are generated when producing SQL (DDL).
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### Entity – Node Problems
This section highlights potential issues with the entity definition:
* **Errors** – Configuration problems that must be resolved
* **Warnings** – Suggestions or best‑practice notices
These indicators help ensure that the entity is correctly designed before deployment.
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### Entity – Preview SQL (DDL)
This option generates the **SQL Data Definition Language (DDL)** for the selected entity.
It allows users to preview the CREATE TABLE statement before exporting or deploying the schema.
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### Entity – Delete
This option deletes the entity (table) from the data model.
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### Summary
The **Entity Properties** panel is the central place for defining and managing database tables in Data Designer.
Through this panel, users can:
* Define table metadata and structure
* Manage columns and constraints
* Generate SQL (DDL) for deployment
* Validate entity configuration
* Maintain clean, well‑structured data models
This structured approach makes **Entity Properties** a core building block of ONEWEB’s **low‑code data modeling workflow**.
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