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.

Sign up for GitHub

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

Implement comparisons on nested data types such that distinct/except would work #11117

Merged
merged 1 commit into from
Jun 27, 2024
Merged

Implement comparisons on nested data types such that distinct/except would work #11117

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
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
76 changes: 76 additions & 0 deletions datafusion/core/src/dataframe/mod.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3445,6 +3445,82 @@ mod tests {
Ok(())
}

#[tokio::test]
async fn test_except_nested_struct() -> Result<()> {
use arrow::array::StructArray;

let nested_schema = Arc::new(Schema::new(vec![
Field::new("id", DataType::Int32, true),
Field::new("lat", DataType::Int32, true),
Field::new("long", DataType::Int32, true),
]));
let schema = Arc::new(Schema::new(vec![
Field::new("value", DataType::Int32, true),
Field::new(
"nested",
DataType::Struct(nested_schema.fields.clone()),
true,
),
]));
let batch = RecordBatch::try_new(
Arc::clone(&schema),
vec![
Arc::new(Int32Array::from(vec![Some(1), Some(2), Some(3)])),
Arc::new(StructArray::from(vec![
(
Arc::new(Field::new("id", DataType::Int32, true)),
Arc::new(Int32Array::from(vec![1, 2, 3])) as ArrayRef,
),
(
Arc::new(Field::new("lat", DataType::Int32, true)),
Arc::new(Int32Array::from(vec![1, 2, 3])) as ArrayRef,
),
(
Arc::new(Field::new("long", DataType::Int32, true)),
Arc::new(Int32Array::from(vec![1, 2, 3])) as ArrayRef,
),
])),
],
)
.unwrap();

let updated_batch = RecordBatch::try_new(
Arc::clone(&schema),
vec![
Arc::new(Int32Array::from(vec![Some(1), Some(12), Some(3)])),
Arc::new(StructArray::from(vec![
(
Arc::new(Field::new("id", DataType::Int32, true)),
Arc::new(Int32Array::from(vec![1, 2, 3])) as ArrayRef,
),
(
Arc::new(Field::new("lat", DataType::Int32, true)),
Arc::new(Int32Array::from(vec![1, 2, 3])) as ArrayRef,
),
(
Arc::new(Field::new("long", DataType::Int32, true)),
Arc::new(Int32Array::from(vec![1, 2, 3])) as ArrayRef,
),
])),
],
)
.unwrap();

let ctx = SessionContext::new();
let before = ctx.read_batch(batch).expect("Failed to make DataFrame");
let after = ctx
.read_batch(updated_batch)
.expect("Failed to make DataFrame");

let diff = before
.except(after)
.expect("Failed to except")
.collect()
.await?;
assert_eq!(diff.len(), 1);
Ok(())
}

#[tokio::test]
async fn nested_explain_should_fail() -> Result<()> {
let ctx = SessionContext::new();
Expand Down
14 changes: 13 additions & 1 deletion datafusion/physical-plan/src/joins/hash_join.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -52,13 +52,15 @@ use arrow::array::{
Array, ArrayRef, BooleanArray, BooleanBufferBuilder, PrimitiveArray, UInt32Array,
UInt64Array,
};
use arrow::buffer::NullBuffer;
use arrow::compute::kernels::cmp::{eq, not_distinct};
use arrow::compute::{and, concat_batches, take, FilterBuilder};
use arrow::datatypes::{Schema, SchemaRef};
use arrow::record_batch::RecordBatch;
use arrow::util::bit_util;
use arrow_array::cast::downcast_array;
use arrow_schema::ArrowError;
use arrow_ord::ord::make_comparator;
use arrow_schema::{ArrowError, SortOptions};
use datafusion_common::utils::memory::estimate_memory_size;
use datafusion_common::{
internal_datafusion_err, internal_err, plan_err, project_schema, DataFusionError,
Expand Down Expand Up @@ -1210,6 +1212,16 @@ fn eq_dyn_null(
right: &dyn Array,
null_equals_null: bool,
) -> Result<BooleanArray, ArrowError> {
// Nested datatypes cannot use the underlying not_distinct function and must use a special
// implementation
// <https://github.com/apache/datafusion/issues/10749>
alamb marked this conversation as resolved.
Show resolved Hide resolved
if left.data_type().is_nested() && null_equals_null {
let cmp = make_comparator(left, right, SortOptions::default())?;
let len = left.len().min(right.len());
let values = (0..len).map(|i| cmp(i, i).is_eq()).collect();
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

this is likely quite slow as it will be doing dynamic dispatch per row.

However, slow is better than not working at first.

Could you please: update the name of the function to reflect it isn't just for null anymore? Perhaps we could rename it to eq_dyn or something more generic

Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I think other than the potential rename the PR is ready to go -- however I also think we could do the rename as a follow on PR

Note @jayzhan211 added similiar code to handle nested comparisons in eq_datum in #11091 -- I wonder if we would consolidate those implementations somehow

Copy link
Contributor

@jayzhan211 jayzhan211 Jun 27, 2024 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

We could do the comparison with datum function, I move it to physical-common in #11091
It will be a nice alternative for equal_rows_arr

Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

in #11149

let nulls = NullBuffer::union(left.nulls(), right.nulls());
return Ok(BooleanArray::new(values, nulls));
}
match (left.data_type(), right.data_type()) {
_ if null_equals_null => not_distinct(&left, &right),
_ => eq(&left, &right),
Expand Down