inline-sql

Write SQL queries inside Rust functions.

The inline-sql crate lets you annotate a function to directly write an SQL query as the function body. You can use the function parameters as placeholders in your query, and the query result will automatically be converted to the return type.

See the documentation of the #[inline_sql] macro for more details.

Currently, only tokio-postgres is supported as backend.

Example: Ignore the query output.

use inline_sql::inline_sql;

#[inline_sql]
async fn create_pets_table(
  client: &tokio_postgres::Client
) -> Result<(), tokio_postgres::Error> {
  query! {
    CREATE TABLE pets (
      name TEXT PRIMARY KEY,
      species TEXT NOT NULL
    )
  }
}

Example: Return a Vec of rows.

use inline_sql::inline_sql;

#[inline_sql]
async fn get_pets_by_species(
  client: &tokio_postgres::Client,
  species: &str,
) -> Result<Vec<Pet>, tokio_postgres::Error> {
    query!(SELECT * FROM pets WHERE species = #species)
}

Example: Return an Option.

use inline_sql::inline_sql;

#[inline_sql]
async fn get_pet_by_name(
  client: &tokio_postgres::Client,
  name: &str,
) -> Result<Option<Pet>, tokio_postgres::Error> {
    query!(SELECT * FROM pets WHERE name = #name)
}

Example: Return the number of affected rows.

use inline_sql::inline_sql;

#[inline_sql]
async fn rename_species(
  client: &tokio_postgres::Client,
  old_species: &str,
  new_species: &str,
) -> Result<u64, tokio_postgres::Error> {
    query!(UPDATE pets SET species = #new_species WHERE species = #old_species)
}

Planned features:

• Support for more backends, including synchronous backends.
• Parsing the function arguments to determine the name of the client object.
• Support for queries that return exactly one row or an error.
• More attribute arguments to allow:
  • Specifying the query type instead of deducing it from the return type.
  • Changing how the client is obtained in the generated code (for example, from a member of self).