wehub-resource-sync
90 lines
2.0 KiB
Markdown
90 lines
2.0 KiB
Markdown
# Rust
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Install via `cargo`:
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```bash
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cargo add perspective
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```
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# Example
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Initialize a server and client
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```rust
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let server = Server::default();
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let client = server.new_local_client();
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```
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Load an Arrow
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```rust
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let mut file = File::open(std::path::Path::new(ROOT_PATH).join(ARROW_FILE_PATH))?;
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let mut feather = Vec::with_capacity(file.metadata()?.len() as usize);
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file.read_to_end(&mut feather)?;
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let data = UpdateData::Arrow(feather.into());
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let mut options = TableInitOptions::default();
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options.set_name("my_data_source");
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client.table(data.into(), options).await?;
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```
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# Joining Tables
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`Client::join` creates a read-only `Table` by joining two source tables on a
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shared key column. The result is reactive — it updates automatically when
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either source table changes. See [`Join`](../explanation/join.md) for
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conceptual details.
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```rust
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let orders = client.table(
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TableData::Update(UpdateData::JsonRows(
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"[{\"id\":1,\"product_id\":101,\"qty\":5},{\"id\":2,\"product_id\":102,\"qty\":3}]".into(),
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)),
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TableInitOptions::default(),
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).await?;
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let products = client.table(
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TableData::Update(UpdateData::JsonRows(
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"[{\"product_id\":101,\"name\":\"Widget\"},{\"product_id\":102,\"name\":\"Gadget\"}]".into(),
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)),
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TableInitOptions::default(),
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).await?;
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let joined = client.join(
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(&orders).into(),
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(&products).into(),
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"product_id",
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JoinOptions::default(),
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).await?;
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let view = joined.view(None).await?;
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let json = view.to_json().await?;
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```
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Use `JoinOptions` to configure the join type, table name, or `right_on` column:
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```rust
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let options = JoinOptions {
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join_type: Some(JoinType::Left),
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name: Some("orders_with_products".into()),
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right_on: None,
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};
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let joined = client.join(
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(&orders).into(),
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(&products).into(),
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"product_id",
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options,
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).await?;
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```
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You can also join by table name strings instead of `Table` references:
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```rust
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let joined = client.join(
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"orders".into(),
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"products".into(),
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"product_id",
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JoinOptions::default(),
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).await?;
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```
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