yordan-pavlov commented on a change in pull request #1248:
URL: https://github.com/apache/arrow-rs/pull/1248#discussion_r799629375



##########
File path: arrow/src/compute/kernels/filter.rs
##########
@@ -185,79 +287,564 @@ pub fn prep_null_mask_filter(filter: &BooleanArray) -> 
BooleanArray {
 /// # Ok(())
 /// # }
 /// ```
-pub fn filter(array: &dyn Array, predicate: &BooleanArray) -> Result<ArrayRef> 
{
-    if predicate.null_count() > 0 {
-        // this greatly simplifies subsequent filtering code
-        // now we only have a boolean mask to deal with
-        let predicate = prep_null_mask_filter(predicate);
-        return filter(array, &predicate);
+pub fn filter(values: &dyn Array, predicate: &BooleanArray) -> 
Result<ArrayRef> {
+    let predicate = FilterBuilder::new(predicate).build();
+    filter_array(values, &predicate)
+}
+
+/// Returns a new [RecordBatch] with arrays containing only values matching 
the filter.
+pub fn filter_record_batch(
+    record_batch: &RecordBatch,
+    predicate: &BooleanArray,
+) -> Result<RecordBatch> {
+    let filter = FilterBuilder::new(predicate).optimize().build();
+
+    let filtered_arrays = record_batch
+        .columns()
+        .iter()
+        .map(|a| filter_array(a, &filter))
+        .collect::<Result<Vec<_>>>()?;
+
+    RecordBatch::try_new(record_batch.schema(), filtered_arrays)
+}
+
+/// A builder to construct [`FilterPredicate`]
+#[derive(Debug)]
+pub struct FilterBuilder {
+    filter: BooleanArray,
+    count: usize,
+    iterator: FilterIterator,
+}
+
+impl FilterBuilder {
+    /// Create a new [`FilterBuilder`] that can be used to construct a 
[`FilterPredicate`]
+    pub fn new(filter: &BooleanArray) -> Self {
+        let filter = match filter.null_count() {
+            0 => BooleanArray::from(filter.data().clone()),
+            _ => prep_null_mask_filter(filter),
+        };
+
+        let count = filter_count(&filter);
+        let selectivity_frac = count as f64 / filter.len() as f64;
+        let iterator = if selectivity_frac > 
FILTER_SLICES_SELECTIVITY_THRESHOLD {
+            FilterIterator::SlicesIterator

Review comment:
       here `FilterIterator` looks more like `FilterIteratorType`, as in this 
is no the actual iterator




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