feat: spark udf array shuffle

datafusion/spark/Cargo.toml

@@ -45,12 +45,12 @@ datafusion-execution = { workspace = true }
 datafusion-expr = { workspace = true }
 datafusion-functions = { workspace = true, features = ["crypto_expressions"] }
 log = { workspace = true }
+rand = { workspace = true }
 sha1 = "0.10"
 url = { workspace = true }
 
 [dev-dependencies]
 criterion = { workspace = true }
-rand = { workspace = true }
 
 [[bench]]
 harness = false

datafusion/spark/src/function/array/mod.rs

@@ -15,20 +15,27 @@
 // specific language governing permissions and limitations
 // under the License.
 
+pub mod shuffle;
 pub mod spark_array;
 
 use datafusion_expr::ScalarUDF;
 use datafusion_functions::make_udf_function;
 use std::sync::Arc;
 
 make_udf_function!(spark_array::SparkArray, array);
+make_udf_function!(shuffle::SparkShuffle, shuffle);
 
 pub mod expr_fn {
     use datafusion_functions::export_functions;
 
     export_functions!((array, "Returns an array with the given elements.", args));
+    export_functions!((
+        shuffle,
+        "Returns a random permutation of the given array.",
+        args
+    ));
 }
 
 pub fn functions() -> Vec<Arc<ScalarUDF>> {
-    vec![array()]
+    vec![array(), shuffle()]
 }

datafusion/spark/src/function/array/shuffle.rs

@@ -0,0 +1,191 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use crate::function::functions_nested_utils::make_scalar_function;
+use arrow::array::{
+    Array, ArrayRef, Capacities, FixedSizeListArray, GenericListArray, MutableArrayData,
+    OffsetSizeTrait,
+};
+use arrow::buffer::OffsetBuffer;
+use arrow::datatypes::DataType::{FixedSizeList, LargeList, List, Null};
+use arrow::datatypes::{DataType, FieldRef};
+use datafusion_common::cast::{
+    as_fixed_size_list_array, as_large_list_array, as_list_array,
+};
+use datafusion_common::{exec_err, utils::take_function_args, Result};
+use datafusion_expr::{ColumnarValue, ScalarUDFImpl, Signature, Volatility};
+use rand::rng;
+use rand::seq::SliceRandom;
+use std::any::Any;
+use std::sync::Arc;
+
+#[derive(Debug, PartialEq, Eq, Hash)]
+pub struct SparkShuffle {
+    signature: Signature,
+}
+
+impl Default for SparkShuffle {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl SparkShuffle {
+    pub fn new() -> Self {
+        Self {
+            signature: Signature::any(1, Volatility::Volatile),
+        }
+    }
+}
+
+impl ScalarUDFImpl for SparkShuffle {
+    fn as_any(&self) -> &dyn Any {
+        self
+    }
+
+    fn name(&self) -> &str {
+        "shuffle"
+    }
+
+    fn signature(&self) -> &Signature {
+        &self.signature
+    }
+
+    fn return_type(&self, arg_types: &[DataType]) -> Result<DataType> {
+        Ok(arg_types[0].clone())
+    }
+
+    fn invoke_with_args(
+        &self,
+        args: datafusion_expr::ScalarFunctionArgs,
+    ) -> Result<ColumnarValue> {
+        make_scalar_function(array_shuffle_inner)(&args.args)
+    }
+}
+
+/// array_shuffle SQL function
+pub fn array_shuffle_inner(arg: &[ArrayRef]) -> Result<ArrayRef> {
+    let [input_array] = take_function_args("shuffle", arg)?;
+    match &input_array.data_type() {
+        List(field) => {
+            let array = as_list_array(input_array)?;
+            general_array_shuffle::<i32>(array, field)
+        }
+        LargeList(field) => {
+            let array = as_large_list_array(input_array)?;
+            general_array_shuffle::<i64>(array, field)
+        }
+        FixedSizeList(field, _) => {
+            let array = as_fixed_size_list_array(input_array)?;
+            fixed_size_array_shuffle(array, field)
+        }
+        Null => Ok(Arc::clone(input_array)),
+        array_type => exec_err!("shuffle does not support type '{array_type}'."),
+    }
+}
+
+fn general_array_shuffle<O: OffsetSizeTrait + TryFrom<i64>>(
+    array: &GenericListArray<O>,
+    field: &FieldRef,
+) -> Result<ArrayRef> {
+    let values = array.values();
+    let original_data = values.to_data();
+    let capacity = Capacities::Array(original_data.len());
+    let mut offsets = vec![O::usize_as(0)];
+    let mut nulls = vec![];
+    let mut mutable =
+        MutableArrayData::with_capacities(vec![&original_data], false, capacity);
+    let mut rng = rng();
+
+    for (row_index, offset_window) in array.offsets().windows(2).enumerate() {
+        // skip the null value
+        if array.is_null(row_index) {
+            nulls.push(false);
+            offsets.push(offsets[row_index] + O::one());
+            mutable.extend(0, 0, 1);
+            continue;
+        }
+        nulls.push(true);
+        let start = offset_window[0];
+        let end = offset_window[1];
+        let length = (end - start).to_usize().unwrap();
+
+        // Create indices and shuffle them
+        let mut indices: Vec<usize> =
+            (start.to_usize().unwrap()..end.to_usize().unwrap()).collect();
+        indices.shuffle(&mut rng);
+
+        // Add shuffled elements
+        for &index in &indices {
+            mutable.extend(0, index, index + 1);
+        }
+
+        offsets.push(offsets[row_index] + O::usize_as(length));
+    }
+
+    let data = mutable.freeze();
+    Ok(Arc::new(GenericListArray::<O>::try_new(
+        Arc::clone(field),
+        OffsetBuffer::<O>::new(offsets.into()),
+        arrow::array::make_array(data),
+        Some(nulls.into()),
+    )?))
+}
+
+fn fixed_size_array_shuffle(
+    array: &FixedSizeListArray,
+    field: &FieldRef,
+) -> Result<ArrayRef> {
+    let values = array.values();
+    let original_data = values.to_data();
+    let capacity = Capacities::Array(original_data.len());
+    let mut nulls = vec![];
+    let mut mutable =
+        MutableArrayData::with_capacities(vec![&original_data], false, capacity);
+    let value_length = array.value_length() as usize;
+    let mut rng = rng();
+
+    for row_index in 0..array.len() {
+        // skip the null value
+        if array.is_null(row_index) {
+            nulls.push(false);
+            mutable.extend(0, 0, value_length);
+            continue;
+        }
+        nulls.push(true);
+
+        let start = row_index * value_length;
+        let end = start + value_length;
+
+        // Create indices and shuffle them
+        let mut indices: Vec<usize> = (start..end).collect();
+        indices.shuffle(&mut rng);
+
+        // Add shuffled elements
+        for &index in &indices {
+            mutable.extend(0, index, index + 1);
+        }
+    }
+
+    let data = mutable.freeze();
+    Ok(Arc::new(FixedSizeListArray::try_new(
+        Arc::clone(field),
+        array.value_length(),
+        arrow::array::make_array(data),
+        Some(nulls.into()),
+    )?))
+}

datafusion/sqllogictest/test_files/spark/array/shuffle.slt

@@ -0,0 +1,113 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+
+#   http://www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+# Test shuffle function with simple arrays
+query B
+SELECT array_sort(shuffle([1, 2, 3, 4, 5, NULL])) = [NULL,1, 2, 3, 4, 5];
+----
+true
+
+query B
+SELECT shuffle([1, 2, 3, 4, 5, NULL]) != [1, 2, 3, 4, 5, NULL];
+----
+true
+
+# Test shuffle function with string arrays
+
+query B
+SELECT array_sort(shuffle(['a', 'b', 'c', 'd', 'e', 'f'])) = ['a', 'b', 'c', 'd', 'e', 'f'];
+----
+true
+
+query B
+SELECT shuffle(['a', 'b', 'c', 'd', 'e', 'f']) != ['a', 'b', 'c', 'd', 'e', 'f'];;
+----
+true
+
+# Test shuffle function with empty array
+query ?
+SELECT shuffle([]);
+----
+[]
+
+# Test shuffle function with single element
+query ?
+SELECT shuffle([42]);
+----
+[42]
+
+# Test shuffle function with null array
+query ?
+SELECT shuffle(NULL);
+----
+NULL
+
+# Test shuffle function with fixed size list arrays
+query B
+SELECT array_sort(shuffle(arrow_cast([1, 2, NULL, 3, 4, 5], 'FixedSizeList(6, Int64)'))) = [NULL, 1, 2, 3, 4, 5];
+----
+true
+
+query B
+SELECT shuffle(arrow_cast([1, 2, NULL, 3, 4, 5], 'FixedSizeList(6, Int64)')) != [1, 2, NULL, 3, 4, 5];
+----
+true
+
+# Test shuffle on table data with different list types
+statement ok
+CREATE TABLE test_shuffle_list_types AS VALUES
+  ([1, 2, 3, 4]),
+  ([5, 6, 7, 8, 9]),
+  ([10]),
+  (NULL),
+  ([]);
+
+# Test shuffle with large list from table
+query ?
+SELECT array_sort(shuffle(column1)) FROM test_shuffle_list_types;
+----
+[1, 2, 3, 4]
+[5, 6, 7, 8, 9]
+[10]
+NULL
+[]
+
+# Test fixed size list table
+statement ok
+CREATE TABLE test_shuffle_fixed_size AS VALUES
+  (arrow_cast([1, 2, 3], 'FixedSizeList(3, Int64)')),
+  (arrow_cast([4, 5, 6], 'FixedSizeList(3, Int64)')),
+  (arrow_cast([NULL, 8, 9], 'FixedSizeList(3, Int64)')),
+  (NULL);
+
+# Test shuffle with fixed size list from table
+query ?
+SELECT array_sort(shuffle(column1)) FROM test_shuffle_fixed_size;
+----
+[1, 2, 3]
+[4, 5, 6]
+[NULL, 8, 9]
+NULL
+
+# Clean up
+statement ok
+DROP TABLE test_shuffle_list_types;
+
+statement ok
+DROP TABLE test_shuffle_fixed_size;
+
+