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| |
| # SessionContext |
| |
| `SessionContext` is the entry point into DataFusion from Java. It owns the |
| catalog of registered tables and the query planner. |
| |
| ## Lifecycle |
| |
| ```java |
| try (SessionContext ctx = new SessionContext()) { |
| // register tables, build queries... |
| } |
| ``` |
| |
| `SessionContext` is `AutoCloseable`. Closing it releases the underlying |
| native context. Use `try`-with-resources so the native side is freed even |
| on exception. |
| |
| ## Threading |
| |
| A `SessionContext` is **not thread-safe**. Do not share one across threads |
| without external synchronization. The simplest pattern is one context per |
| thread. |
| |
| ## What's configurable today |
| |
| Today, `SessionContext` exposes only data-source registration and query |
| construction. Tuning knobs that DataFusion offers natively |
| (`SessionConfig`, `RuntimeEnv`) are not yet wired through the Java API. |
| See [Project status](project-status.md) for the current shape of the API. |
