// Copyright Materialize, Inc. and contributors. All rights reserved.
//
// Use of this software is governed by the Business Source License
// included in the LICENSE file.
//
// As of the Change Date specified in that file, in accordance with
// the Business Source License, use of this software will be governed
// by the Apache License, Version 2.0.
//! Transformations that fuse together others of their kind.
pub mod filter;
pub mod join;
pub mod map;
pub mod negate;
pub mod project;
pub mod reduce;
pub mod top_k;
pub mod union;
use mz_expr::MirRelationExpr;
use crate::TransformCtx;
/// Fuses multiple like operators together when possible.
#[derive(Debug)]
pub struct Fusion;
impl crate::Transform for Fusion {
fn name(&self) -> &'static str {
"Fusion"
}
#[mz_ore::instrument(
target = "optimizer",
level = "debug",
fields(path.segment = "fusion")
)]
fn actually_perform_transform(
&self,
relation: &mut MirRelationExpr,
_: &mut TransformCtx,
) -> Result<(), crate::TransformError> {
use mz_expr::visit::Visit;
relation.visit_mut_post(&mut Self::action)?;
mz_repr::explain::trace_plan(&*relation);
Ok(())
}
}
impl Fusion {
/// Apply fusion action for variants we know how to fuse.
pub(crate) fn action(expr: &mut MirRelationExpr) {
match expr {
MirRelationExpr::Filter { .. } => filter::Filter::action(expr),
MirRelationExpr::Map { .. } => map::Map::action(expr),
MirRelationExpr::Project { .. } => project::Project::action(expr),
MirRelationExpr::Negate { .. } => negate::Negate::action(expr),
MirRelationExpr::TopK { .. } => top_k::TopK::action(expr),
MirRelationExpr::Union { .. } => union::Union::action(expr),
_ => {}
}
}
}