Examples

Kotlin Database CRUD

Building a CRUD App

Kotlin database CRUD with Exposed handles data operations.

Introduction to Exposed

Exposed is a lightweight SQL library for Kotlin that simplifies database interactions. It provides a DSL for SQL queries and automates repetitive tasks, allowing developers to focus on business logic rather than database operations.

Setting Up Exposed in Your Project

To use Exposed in your Kotlin project, you'll need to add the necessary dependencies to your build.gradle.kts file. Exposed supports various databases such as H2, MySQL, PostgreSQL, and more.

Connecting to a Database

Before performing CRUD operations, establish a connection to your database. Use the Exposed Database.connect() method to initiate the connection.

Creating a Table

Define tables in Exposed using object declarations. This example demonstrates how to create a simple Users table.

CRUD Operations

Exposed makes CRUD operations straightforward. Here, we'll go through each operation: Create, Read, Update, and Delete.

Create Operation

Insert a new record into the Users table using the insert method.

Read Operation

To retrieve data, use the selectAll method or specify conditions with select.

Update Operation

Update existing records with the update method. Specify the condition and the new values.

Delete Operation

Remove records using the deleteWhere method, specifying the condition for deletion.

Examples

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