Added support to read dictionary-encoded required parquet pages

src/io/parquet/read/fixed_size_binary.rs

@@ -70,6 +70,31 @@ pub(crate) fn read_dict_buffer(
  }
 }
 
+/// Assumptions: No rep levels
+pub(crate) fn read_dict_required(
+ indices_buffer: &[u8],
+ additional: usize,
+ size: usize,
+ dict: &FixedLenByteArrayPageDict,
+ values: &mut MutableBuffer<u8>,
+ validity: &mut MutableBitmap,
+) {
+ let dict_values = dict.values();
+
+ // SPEC: Data page format: the bit width used to encode the entry ids stored as 1 byte (max bit width = 32),
+ // SPEC: followed by the values encoded using RLE/Bit packed described above (with the given bit width).
+ let bit_width = indices_buffer[0];
+ let indices_buffer = &indices_buffer[1..];
+
+ let indices = hybrid_rle::HybridRleDecoder::new(indices_buffer, bit_width as u32, additional);
+
+ for index in indices {
+ let index = index as usize;
+ values.extend_from_slice(&dict_values[index * size..(index + 1) * size]);
+ }
+ validity.extend_constant(additional * size, true);
+}
+
 pub(crate) fn read_optional(
  validity_buffer: &[u8],
  values_buffer: &[u8],
@@ -217,6 +242,14 @@ pub(crate) fn extend_from_page(
  values,
  validity,
  ),
+ (Encoding::PlainDictionary, Some(dict), false) => read_dict_required(
+ values_buffer,
+ additional,
+ size,
+ dict.as_any().downcast_ref().unwrap(),
+ values,
+ validity,
+ ),
  (Encoding::Plain, _, true) => read_optional(
  validity_buffer,
  values_buffer,

tests/it/io/parquet/read.rs

@@ -313,6 +313,11 @@ fn v2_decimal_9_required() -> Result<()> {
  test_pyarrow_integration(6, 2, "basic", false, true, None)
 }
 
+#[test]
+fn v2_decimal_9_required_dict() -> Result<()> {
+ test_pyarrow_integration(6, 2, "basic", true, true, None)
+}
+
 #[test]
 fn v2_decimal_18_nullable() -> Result<()> {
  test_pyarrow_integration(8, 2, "basic", false, false, None)
@@ -323,6 +328,11 @@ fn v2_decimal_18_required() -> Result<()> {
  test_pyarrow_integration(7, 2, "basic", false, true, None)
 }
 
+#[test]
+fn v2_decimal_18_required_dict() -> Result<()> {
+ test_pyarrow_integration(7, 2, "basic", true, true, None)
+}
+
 #[test]
 fn v2_decimal_26_nullable() -> Result<()> {
  test_pyarrow_integration(9, 2, "basic", false, false, None)
@@ -333,6 +343,11 @@ fn v2_decimal_26_required() -> Result<()> {
  test_pyarrow_integration(8, 2, "basic", false, true, None)
 }
 
+#[test]
+fn v2_decimal_26_required_dict() -> Result<()> {
+ test_pyarrow_integration(8, 2, "basic", true, true, None)
+}
+
 #[test]
 fn v1_struct_optional() -> Result<()> {
  test_pyarrow_integration(0, 1, "struct", false, false, None)