[arrow-datafusion] branch master updated: Add execution module doc (#2655)

[tu...@apache.org]

This is an automated email from the ASF dual-hosted git repository.

tustvold pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/arrow-datafusion.git


The following commit(s) were added to refs/heads/master by this push:
     new 400884fa1 Add execution module doc (#2655)
400884fa1 is described below

commit 400884fa165c305019b33c887240c384472ce1e0
Author: Raphael Taylor-Davies <17...@users.noreply.github.com>
AuthorDate: Mon May 30 19:24:32 2022 +0100

    Add execution module doc (#2655)
---
 datafusion/core/src/execution/mod.rs | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/datafusion/core/src/execution/mod.rs b/datafusion/core/src/execution/mod.rs
index a353e1640..85a9f8b4e 100644
--- a/datafusion/core/src/execution/mod.rs
+++ b/datafusion/core/src/execution/mod.rs
@@ -15,7 +15,30 @@
 // specific language governing permissions and limitations
 // under the License.
 
-//! DataFusion query execution
+//! This module contains the shared state available at different parts
+//! of query planning and execution
+//!
+//! # Runtime Environment
+//!
+//! [`runtime_env::RuntimeEnv`] can be created from a [`runtime_env::RuntimeConfig`] and
+//! stores state to be shared across multiple sessions. In most applications there will
+//! be a single [`runtime_env::RuntimeEnv`] for the entire process
+//!
+//! # Session Context
+//!
+//! [`context::SessionContext`] can be created from a [`context::SessionConfig`] and
+//! an optional [`runtime_env::RuntimeConfig`], and stores the state for a particular
+//! query session.
+//!
+//! In particular [`context::SessionState`] is the information available to query planning
+//!
+//! # Task Context
+//!
+//! [`context::TaskContext`] is typically created from a [`context::SessionContext`] or
+//! [`context::SessionState`], and represents the state available to query execution.
+//!
+//! In particular it is the state passed to [`crate::physical_plan::ExecutionPlan::execute`]
+//!
 
 pub mod context;
 pub mod disk_manager;