Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Add assertion for invariant in create_physical_expression and fix ViewTable projection #3242

Merged
merged 6 commits into from
Aug 25, 2022
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
53 changes: 51 additions & 2 deletions datafusion/core/src/datasource/view.rs
Original file line number Diff line number Diff line change
Expand Up @@ -21,6 +21,7 @@ use std::{any::Any, sync::Arc};

use arrow::datatypes::SchemaRef;
use async_trait::async_trait;
use datafusion_expr::LogicalPlanBuilder;

use crate::{
error::Result,
Expand Down Expand Up @@ -81,14 +82,36 @@ impl TableProvider for ViewTable {
async fn scan(
&self,
state: &SessionState,
_projection: &Option<Vec<usize>>,
projection: &Option<Vec<usize>>,
_filters: &[Expr],
_limit: Option<usize>,
) -> Result<Arc<dyn ExecutionPlan>> {
// clone state and start_execution so that now() works in views
let mut state_cloned = state.clone();
state_cloned.execution_props.start_execution();
state_cloned.create_physical_plan(&self.logical_plan).await
if let Some(projection) = projection {
// avoiding adding a redundant projection (e.g. SELECT * FROM view)
let current_projection =
(0..self.logical_plan.schema().fields().len()).collect::<Vec<usize>>();
if projection == &current_projection {
state_cloned.create_physical_plan(&self.logical_plan).await
} else {
let fields: Vec<Expr> = projection
.iter()
.map(|i| {
Expr::Column(
self.logical_plan.schema().field(*i).qualified_column(),
)
})
.collect();
let plan = LogicalPlanBuilder::from(self.logical_plan.clone())
.project(fields)?
.build()?;
state_cloned.create_physical_plan(&plan).await
}
} else {
state_cloned.create_physical_plan(&self.logical_plan).await
}
}
}

Expand All @@ -99,6 +122,32 @@ mod tests {

use super::*;

#[tokio::test]
async fn issue_3242() -> Result<()> {
// regression test for https://github.com/apache/arrow-datafusion/pull/3242
let session_ctx = SessionContext::with_config(
SessionConfig::new().with_information_schema(true),
);

session_ctx
.sql("create view v as select 1 as a, 2 as b, 3 as c")
.await?
.collect()
.await?;

let results = session_ctx
.sql("select * from (select b from v)")
.await?
.collect()
.await?;

let expected = vec!["+---+", "| b |", "+---+", "| 2 |", "+---+"];

assert_batches_eq!(expected, &results);

Ok(())
}

#[tokio::test]
async fn create_view_return_empty_dataframe() -> Result<()> {
let session_ctx = SessionContext::new();
Expand Down
2 changes: 1 addition & 1 deletion datafusion/optimizer/src/expr_simplifier.rs
Original file line number Diff line number Diff line change
Expand Up @@ -88,7 +88,7 @@ impl ExprSimplifiable for Expr {
/// ```
fn simplify<S: SimplifyInfo>(self, info: &S) -> Result<Self> {
let mut rewriter = Simplifier::new(info);
let mut const_evaluator = ConstEvaluator::new(info.execution_props());
let mut const_evaluator = ConstEvaluator::try_new(info.execution_props())?;

// TODO iterate until no changes are made during rewrite
// (evaluating constants can enable new simplifications and
Expand Down
16 changes: 7 additions & 9 deletions datafusion/optimizer/src/simplify_expressions.rs
Original file line number Diff line number Diff line change
Expand Up @@ -332,7 +332,7 @@ impl SimplifyExpressions {
/// # use datafusion_expr::expr_rewriter::ExprRewritable;
///
/// let execution_props = ExecutionProps::new();
/// let mut const_evaluator = ConstEvaluator::new(&execution_props);
/// let mut const_evaluator = ConstEvaluator::try_new(&execution_props).unwrap();
///
/// // (1 + 2) + a
/// let expr = (lit(1) + lit(2)) + col("a");
Expand Down Expand Up @@ -403,25 +403,23 @@ impl<'a> ConstEvaluator<'a> {
/// Create a new `ConstantEvaluator`. Session constants (such as
/// the time for `now()` are taken from the passed
/// `execution_props`.
pub fn new(execution_props: &'a ExecutionProps) -> Self {
let input_schema = DFSchema::empty();

pub fn try_new(execution_props: &'a ExecutionProps) -> Result<Self> {
// The dummy column name is unused and doesn't matter as only
// expressions without column references can be evaluated
static DUMMY_COL_NAME: &str = ".";
let schema = Schema::new(vec![Field::new(DUMMY_COL_NAME, DataType::Null, true)]);
let input_schema = DFSchema::try_from(schema.clone())?;

// Need a single "input" row to produce a single output row
let col = new_null_array(&DataType::Null, 1);
let input_batch =
RecordBatch::try_new(std::sync::Arc::new(schema), vec![col]).unwrap();
let input_batch = RecordBatch::try_new(std::sync::Arc::new(schema), vec![col])?;

Self {
Ok(Self {
can_evaluate: vec![],
execution_props,
input_schema,
input_batch,
}
})
}

/// Can a function of the specified volatility be evaluated?
Expand Down Expand Up @@ -1273,7 +1271,7 @@ mod tests {
var_providers: None,
};

let mut const_evaluator = ConstEvaluator::new(&execution_props);
let mut const_evaluator = ConstEvaluator::try_new(&execution_props).unwrap();
let evaluated_expr = input_expr
.clone()
.rewrite(&mut const_evaluator)
Expand Down
11 changes: 10 additions & 1 deletion datafusion/physical-expr/src/planner.rs
Original file line number Diff line number Diff line change
Expand Up @@ -31,13 +31,22 @@ use datafusion_expr::binary_rule::comparison_coercion;
use datafusion_expr::{Expr, Operator};
use std::sync::Arc;

/// Create a physical expression from a logical expression ([Expr])
/// Create a physical expression from a logical expression ([Expr]).
///
/// # Arguments
///
/// * `e` - The logical expression
/// * `input_dfschema` - The DataFusion schema for the input, used to resolve `Column` references
/// to qualified or unqualified fields by name.
/// * `input_schema` - The Arrow schema for the input, used for determining expression data types
/// when performing type coercion.
pub fn create_physical_expr(
e: &Expr,
input_dfschema: &DFSchema,
input_schema: &Schema,
execution_props: &ExecutionProps,
) -> Result<Arc<dyn PhysicalExpr>> {
assert_eq!(input_schema.fields.len(), input_dfschema.fields().len());
match e {
Expr::Alias(expr, ..) => Ok(create_physical_expr(
expr,
Expand Down