Scala Slick is a modern database query and access library for Scala. It allows you to work with relational databases using Scala code, providing a type-safe and composable API for database operations.

Key Features of Slick

Type-safe queries
Composable query abstractions
Support for multiple database systems
Asynchronous execution
Functional programming approach

Getting Started with Slick

To use Slick in your Scala project, you need to add the following dependency to your SBT build file:

libraryDependencies += "com.typesafe.slick" %% "slick" % "3.3.3"

Defining Table Schemas

In Slick, you define your database schema using Scala case classes and Table objects. Here's an example:


import slick.jdbc.H2Profile.api._

case class User(id: Int, name: String, email: String)

class Users(tag: Tag) extends Table[User](tag, "USERS") {
  def id = column[Int]("ID", O.PrimaryKey, O.AutoInc)
  def name = column[String]("NAME")
  def email = column[String]("EMAIL")
  def * = (id, name, email) <> (User.tupled, User.unapply)
}

val users = TableQuery[Users]

Querying the Database

Slick provides a powerful DSL for querying the database. Here's an example of a simple query:


val query = users.filter(_.name like "%John%")
val result: Future[Seq[User]] = db.run(query.result)

Inserting Data

Inserting data into the database is straightforward with Slick:


val insertAction = users += User(0, "Alice", "alice@example.com")
val insertResult: Future[Int] = db.run(insertAction)

Best Practices

Use Futures for asynchronous operations
Leverage type inference for cleaner code
Utilize case classes for domain models
Implement proper error handling using Try or Either

Advanced Features

Slick offers advanced features like:

Compiled queries for better performance
Custom column mappings
Plain SQL support for complex queries
Integration with Play Framework

By mastering Scala Slick, you can efficiently work with databases in your Scala applications, leveraging the power of functional programming and type safety.