description: ToolJet is an open-source low-code framework to build and deploy custom internal tools. ToolJet can connect to your data sources such as databases ( PostgreSQL, MongoDB, MS SQL Server, Snowflake, , BigQuery, etc ), API/GraphQL endpoints, SaaS tools ( Airtable, Stripe, Google Sheets, etc ) and cloud object storage services ( AWS S3, Google Cloud Storage and Minio ). Once the data sources are connected, ToolJet can run queries on these data sources to fetch and update data. The data fetched from data sources can be visualised and modified using the UI widgets such as tables, charts, forms, etc.
ToolJet ships with its built-in database called **[ToolJet DB](/docs/tooljet-database)** (built on top of PostgreSQL). You can also connect to the **external data sources** such as **databases** ( PostgreSQL, MongoDB, MS SQL Server, Snowflake, , BigQuery, etc ), **API/GraphQL endpoints**, **SaaS tools** ( Airtable, Stripe, Google Sheets, etc ) and **cloud object storage services** ( AWS S3, Google Cloud Storage and Minio ).
Once the data sources are connected, ToolJet can run **queries** on these data sources to fetch and update data. The data fetched from data sources can be **visualised and modified** using the UI widgets such as tables, charts, forms, etc. You can also use **[Javascript](/docs/data-sources/run-js)** or **[Python](/docs/data-sources/run-py)** queries for writing business logic or interacting with the user interface of the application.
When you're building an internal tool, there are a lot of tools and frameworks available. But with ToolJet, you can save developers' hours by allowing them to build full-stack business applications in minutes.
- **Open-Source**: ToolJet is Open-Source, you can go through the ToolJet codebase on **[GitHub](https://github.com/ToolJet/ToolJet)** or you can **deploy ToolJet on your infrastructure**.
- **Full-stack platform**: ToolJet has a **[built-in database](/docs/tooljet-database)**, **[External datasources](/docs/data-sources/airtable)**, and a frontend builder so you can build a full-stack app right inside it. ToolJet comes with Custom Component for importing your own **react components** and the ability to write custom **JavaScript** and **Python** code.
- **Extensible**: Didn't find the **component** or **datasource** that fit your application's requirements? You can always build your own **component** and **datasource** using our **plugin development kit**.
- **Powerful Apps**: With ToolJet, developers can quickly build powerful custom internal tools for their Support, Operations and Sales teams. Build CRUD apps, Dashboards, Admin Panels, CRMs and much more.
1.**Connect to datasources:** Connect to the ToolJet's built-in database **[ToolJet DB](/docs/tooljet-database)** (built on top of PostgreSQL) or your existing data sources such as PostgreSQL, MySQL, Firestore, Stripe, Google Sheets, API endpoints, etc.
2.**Build queries:** ToolJet comes with query builders for all supported data sources. You can also write **[Javascript](/docs/data-sources/run-js)** or **[Python](/docs/data-sources/run-py)** queries or use **[Transformations](/docs/tutorial/transformations)** to transform the query response.
3.**Build User Interface:** ToolJet's visual **[App Builder](/docs/app-builder/overview)** allows you to drag and drop components ( Eg: tables, charts, forms, etc ) to quickly build the user-interface of the apps. Components have events such as `on click`, `on row selected`, `on page changed`, etc. ToolJet apps can be used in light and dark mode.
ToolJet binds together the datasources, queries and components to convert business logic into custom applications. You can also secure your ToolJet apps with **[Group & Permissions](/docs/org-management/permissions)** and **[Audit Logging](/docs/Enterprise/audit_logs)**.
- **[Deploy on premise](/docs/setup/)**: recommended method for production or customized use cases. You'll find Server setup guides for popular platforms (AWS, GCP, Kubernetes etc) and one-click deployment guides (Heroku, DigitalOcean etc).
Let's say you're an eCommerce company and your **Customer Support/Operations** team need a **Support Tool/Admin** panel for managing the orders, updating inventory, and track revenue and metrics. This quickstart will guide you through building your first custom internal tool in less than 5 minutes.
2. When you click on create new app the **App-builder** will open up. You can rename your application from `untitled` to **Support Tool** from the top left of app-builder.
ToolJet application's User interface is constructed using Components like Tables, Forms, Charts, or Buttons etc. Check **[Components Catalog](/docs/widgets/overview)** to learn more.
1. We can add a new datasource from the **Datasource manager** on the left-sidebar of the app builder but since we are using **ToolJet Database** we don't need to add any external datasource. Go to the **Query Panel -> Run ToolJetDb Query**
ToolJet can connect to several databases, APIs and external services to fetch and modify data. Check **[Datasource Catalog](/docs/data-sources/overview)** to learn more.
2. Choose a **Table** from the dropdown, Select the **List rows** option from the **Operation** dropdown, You can leave other query parameters. Scroll down and enable **Run this query on application load** - this will trigger the query when the app is loaded.
3. Click on **Create** to create the query and then click **Run** to trigger the query and get response. You can also check the query response by clicking **Preview** button without firing the query.
4. Go to the **Table properties** by clicking on the component handle and bind the data returned by the query in the **Table data** property. When building apps in ToolJet anything inside `{{}}` is JavaScript and we javascript dot notation to get the data from query and populate the table using **{{queries.tooljetdb1.data}}**. The table will be auto-populated once the table data is entered.
5. Let's create another query that will get the data from the **input fields** and will add a new row in the tooljet database. **Create New Query** -> **Select Table (Customers)** -> **Select Operation (Create row)** -> add the following columns with the respective value:
4.**created_at** - `{{moment().format("DD/MM/YYYY hh:mm A")}}` (We are using **momentjs library** to get the current date from the system rather than getting input by the user )
You can also add event handler to this query for **On Success** event to run the `tooljetdb1` query that populates the table, so that whenever this is successful the table is refreshed.
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6. Now, let's bind this query to the **Add Product** button. Click on the button handle to open its properties, **Add an handler** -> **Select Event (On Click)** -> **Select Action (Run Query)** -> **Select Query (tooljetdb2)**.
- You can manipulate the data returned by the queries using **[Transformations](/docs/tutorial/transformations)**
- You can also **[Run JavaScript code](/docs/data-sources/run-js)** or **[Run Python code](/docs/data-sources/run-py)** to perform custom behavior inside ToolJet
3.**Share** option allows you to share the **released version** of the application with other users or you can also make the app **public** and anyone with the URL will be able to use the app.
If you are building internal tool for your organization, here are few tutorials of sample use-cases for you to get started:
- **[Build a Feature Request Management App](https://youtu.be/c2sbFTDUMzs)**
- **[Build a Ticket Triaging App with Baserow and ToolJet](https://blog.tooljet.com/build-a-ticket-triaging-app-with-baserow-and-tooljet/)**
- **[Building a MinIO file explorer app](https://blog.tooljet.com/building-a-minio-file-explorer-app-in-30-minutes/)**
- **[Building a Google Cloud Storage (GCS) file explorer app](https://blog.tooljet.com/build-internal-file-explorer-application-using-google-cloud-storage-gcs-and-tooljet/)**
