feature: rust sqlx local database

README.md

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 # examples
 
 A collection of small code tests and examples to reference later.
+
+## Warning:
+
+I make no guarantees as to the functionality, quality, or state of any example
+in this repository.
+
+You have been warned.
+
+## Layout
+
+This repository is divided based on the tool being tested, with all top-level
+directories referencing a language (if applicable) or a tool (if a language is
+not applicable).
+
+The second layer of directories will each be tests for a single feature,
+library, functionality, etc.

rust/local_database/.gitignore

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+database.db*

rust/local_database/Cargo.toml

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+[package]
+name = "local_database"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+sqlx = { version = "0.8.2", features = ["runtime-tokio-native-tls", "sqlite"] }
+tokio = { version = "1.40.0", features = ["macros", "rt-multi-thread"] }
+#rc-tokio-macros = "2.4.0"

rust/local_database/src/main.rs

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+/// This example was uplled from [this
+/// site](https://tms-dev-blog.com/rust-sqlx-basics-with-sqlite/)
+
+use sqlx::{migrate::MigrateDatabase, FromRow, Row, Sqlite, SqlitePool};
+
+const DB_URL: &str = "./database.db";
+
+#[derive(Clone, FromRow, Debug)]
+struct User {
+    id: i64,
+    name: String,
+}
+
+#[tokio::main]
+async fn main() {
+    // create database if it doesn't exist (skip if it does)
+    if !Sqlite::database_exists(DB_URL).await.unwrap_or(false) {
+        println!("Creating database {}", DB_URL);
+        match Sqlite::create_database(DB_URL).await {
+            Ok(_) => println!("Create db success"),
+            Err(error) => panic!("error: {}", error),
+        }
+    } else {
+        println!("Database already exists");
+    }
+
+    // create table if it doesn't exist (skip if it does)
+    let db = SqlitePool::connect(DB_URL).await.unwrap();
+    let result = sqlx::query(
+        // note that the table layout in this line matches the struct above
+        "create table if not exists users (id integer primary key not null, name varchar(250)
+        not null);"
+    )
+        .execute(&db)
+        .await
+        .unwrap();
+    println!("Create user table result: {:?}", result);
+
+    // list all tables in database
+    let result = sqlx::query(
+        "select name
+        from sqlite_schema
+        where type = 'table'
+        and name not like 'sqlite_%';",
+    )
+        .fetch_all(&db)
+        .await
+        .unwrap();
+    for (idx, row) in result.iter().enumerate() {
+        println!("[{}]: {:?}", idx, row.get::<String, &str>("name"));
+    }
+
+    // insert and extract data from table (note that the data in the table as defined above matches
+    // the struct defined above
+    let result = sqlx::query(
+        "insert into users (name) values (?)"
+    )
+        .bind("bobby")
+        .execute(&db)
+        .await
+        .unwrap();
+    println!("Query results: {:?}", result);
+
+    let user_results = sqlx::query_as::<_, User>(
+        "select id, name from users"
+    )
+        .fetch_all(&db)
+        .await
+        .unwrap();
+    for user in user_results {
+        println!("[{}] name: {}", user.id, &user.name);
+    }
+
+    // delete records
+    let delete_result = sqlx::query(
+        "delete from users where name = $1"
+    )
+        .bind("bobby")
+        .execute(&db)
+        .await
+        .unwrap();
+    println!("Delete result: {:?}", delete_result)
+}