improve array expression doc and clean up array_expression.rs (#9650)

apache · Mar 18, 2024 · e37ac35 · e37ac35
1 parent c072abb
commit e37ac35
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Showing 2 changed files with 49 additions and 70 deletions.
diff --git a/datafusion/physical-expr/src/array_expressions.rs b/datafusion/physical-expr/src/array_expressions.rs
@@ -24,7 +24,6 @@ use arrow::buffer::OffsetBuffer;
 use arrow::datatypes::{DataType, Field};
 use arrow_buffer::NullBuffer;
 
-use arrow_schema::FieldRef;
 use datafusion_common::cast::{as_int64_array, as_large_list_array, as_list_array};
 use datafusion_common::utils::array_into_list_array;
 use datafusion_common::{exec_err, plan_err, Result};
@@ -561,72 +560,3 @@ pub fn array_replace_all(args: &[ArrayRef]) -> Result<ArrayRef> {
         }
     }
 }
-
-/// array_reverse SQL function
-pub fn array_reverse(arg: &[ArrayRef]) -> Result<ArrayRef> {
-    if arg.len() != 1 {
-        return exec_err!("array_reverse needs one argument");
-    }
-
-    match &arg[0].data_type() {
-        DataType::List(field) => {
-            let array = as_list_array(&arg[0])?;
-            general_array_reverse::<i32>(array, field)
-        }
-        DataType::LargeList(field) => {
-            let array = as_large_list_array(&arg[0])?;
-            general_array_reverse::<i64>(array, field)
-        }
-        DataType::Null => Ok(arg[0].clone()),
-        array_type => exec_err!("array_reverse does not support type '{array_type:?}'."),
-    }
-}
-
-fn general_array_reverse<O: OffsetSizeTrait>(
-    array: &GenericListArray<O>,
-    field: &FieldRef,
-) -> Result<ArrayRef>
-where
-    O: TryFrom<i64>,
-{
-    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);
-
-    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;
-        } else {
-            nulls.push(true);
-        }
-
-        let start = offset_window[0];
-        let end = offset_window[1];
-
-        let mut index = end - O::one();
-        let mut cnt = 0;
-
-        while index >= start {
-            mutable.extend(0, index.to_usize().unwrap(), index.to_usize().unwrap() + 1);
-            index = index - O::one();
-            cnt += 1;
-        }
-        offsets.push(offsets[row_index] + O::usize_as(cnt));
-    }
-
-    let data = mutable.freeze();
-    Ok(Arc::new(GenericListArray::<O>::try_new(
-        field.clone(),
-        OffsetBuffer::<O>::new(offsets.into()),
-        arrow_array::make_array(data),
-        Some(nulls.into()),
-    )?))
-}
diff --git a/docs/source/user-guide/sql/scalar_functions.md b/docs/source/user-guide/sql/scalar_functions.md
@@ -1958,6 +1958,7 @@ from_unixtime(expression)
 - [array_extract](#array_extract)
 - [array_fill](#array_fill)
 - [array_indexof](#array_indexof)
+- [array_intersect](#array_intersect)
 - [array_join](#array_join)
 - [array_length](#array_length)
 - [array_ndims](#array_ndims)
@@ -1997,6 +1998,7 @@ from_unixtime(expression)
 - [list_has_all](#list_has_all)
 - [list_has_any](#list_has_any)
 - [list_indexof](#list_indexof)
+- [list_intersect](#list_intersect)
 - [list_join](#list_join)
 - [list_length](#list_length)
 - [list_ndims](#list_ndims)
@@ -2017,6 +2019,7 @@ from_unixtime(expression)
 - [list_replace_all](#list_replace_all)
 - [list_slice](#list_slice)
 - [list_to_string](#list_to_string)
+- [list_union](#list_union)
 - [make_array](#make_array)
 - [make_list](#make_list)
 - [string_to_array](#string_to_array)
@@ -2340,6 +2343,44 @@ flatten(array)
 
 _Alias of [array_position](#array_position)._
 
+### `array_intersect`
+
+Returns an array of elements in the intersection of array1 and array2.
+
+```
+array_intersect(array1, array2)
+```
+
+#### Arguments
+
+- **array1**: Array expression.
+  Can be a constant, column, or function, and any combination of array operators.
+- **array2**: Array expression.
+  Can be a constant, column, or function, and any combination of array operators.
+
+#### Example
+
+```
+❯ select array_intersect([1, 2, 3, 4], [5, 6, 3, 4]);
++----------------------------------------------------+
+| array_intersect([1, 2, 3, 4], [5, 6, 3, 4]);       |
++----------------------------------------------------+
+| [3, 4]                                             |
++----------------------------------------------------+
+❯ select array_intersect([1, 2, 3, 4], [5, 6, 7, 8]);
++----------------------------------------------------+
+| array_intersect([1, 2, 3, 4], [5, 6, 7, 8]);       |
++----------------------------------------------------+
+| []                                                 |
++----------------------------------------------------+
+```
+
+---
+
+#### Aliases
+
+- list_intersect
+
 ### `array_join`
 
 _Alias of [array_to_string](#array_to_string)._
@@ -3068,6 +3109,10 @@ _Alias of [array_has_any](#array_has_any)._
 
 _Alias of [array_position](#array_position)._
 
+### `list_intersect`
+
+_Alias of [array_position](#array_intersect)._
+
 ### `list_join`
 
 _Alias of [array_to_string](#array_to_string)._
@@ -3152,6 +3197,10 @@ _Alias of [array_slice](#array_slice)._
 
 _Alias of [array_to_string](#array_to_string)._
 
+### `list_union`
+
+_Alias of [array_to_string](#array_union)._
+
 ### `make_array`
 
 Returns an Arrow array using the specified input expressions.