rust-sqlx

Async PostgreSQL database access in Rust using SQLx and Tokio. This project demonstrates how to insert and update PostgreSQL enum columns using Rust enums and sqlx.

At the time of writing, clear examples for updating enum fields were hard to find. This demo pulls together the correct patterns in a working example. Hopefully it saves others some time and frustration.

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Running

Before running this demo with PostgreSQL (the primary target database), you'll need to start a local PostgreSQL instance.

The quickest way is to use the official Docker container image:

docker run --rm --network=host --name=postgres \
  -e POSTGRES_PASSWORD=welcome \
  -e POSTGRES_USER=postgres \
  -p 5432:5432 \
  postgres

Then, from another shell window, exec into the database container and initialize the schema:

docker exec -i postgres psql --username=postgres < db-init.sql

Back in the first shell window, set the DATABASE_URL environment variable and run the application:

export DATABASE_URL=postgres://postgres@localhost:5432/postgres
cargo run

You’ll see records being added. Once the table exceeds 10 rows, the program will begin deleting one row for each new insert.

Sample Output

----- 1
----- 2
----- 3: Record { id: 1 }
----- 5

== SELECT users with sqlx::query_as!:

   User { id: 1, name: "Attila the long dead Hun:1", role: User }
----- 6

=== SELECT users with query.map..:
[User { id: 1, name: "Attila the long dead Hun:1", role: User }]
----- 7

=== SELECT users with query.map..:
[User { id: 1, name: "Attila the long dead Hun:1", role: User }]

If you run again you will see more rows added to the table. When the row count is greater than 10 it will delete 1 row for each row added.