fix binary field update

python/python/tests/test_dataset.py

@@ -1339,6 +1339,26 @@ def test_update_dataset_all_types(tmp_path: Path):
     assert dataset.to_table() == expected
 
 
+def test_update_with_binary_field(tmp_path: Path):
+    # Create a lance dataset with binary fields
+    table = pa.Table.from_pydict(
+        {
+            "a": [f"str-{i}" for i in range(100)],
+            "b": [b"bin-{i}" for i in range(100)],
+            "c": list(range(100)),
+        }
+    )
+    dataset = lance.write_dataset(table, tmp_path)
+
+    # Update binary field
+    dataset.update({"b": "X'616263'"}, where="c < 2")
+
+    ds = lance.dataset(tmp_path)
+    assert ds.scanner(filter="c < 2").to_table().column(
+        "b"
+    ).combine_chunks() == pa.array([b"abc", b"abc"])
+
+
 def test_create_update_empty_dataset(tmp_path: Path, provide_pandas: bool):
     base_dir = tmp_path / "dataset"
 

rust/lance/src/io/exec/planner.rs

@@ -357,7 +357,9 @@ impl Planner {
             Value::DollarQuotedString(_) => todo!(),
             Value::EscapedStringLiteral(_) => todo!(),
             Value::NationalStringLiteral(_) => todo!(),
-            Value::HexStringLiteral(_) => todo!(),
+            Value::HexStringLiteral(hsl) => {
+                Expr::Literal(ScalarValue::Binary(Self::try_decode_hex_literal(hsl)))
+            }
             Value::DoubleQuotedString(s) => Expr::Literal(ScalarValue::Utf8(Some(s.clone()))),
             Value::Boolean(v) => Expr::Literal(ScalarValue::Boolean(Some(*v))),
             Value::Null => Expr::Literal(ScalarValue::Null),
@@ -673,6 +675,42 @@ impl Planner {
         Ok(resolved)
     }
 
+    /// Try to decode bytes from hex literal string.
+    ///
+    /// Copied from datafusion because this is not public.
+    ///
+    /// TODO: use SqlToRel from Datafusion directly?
+    fn try_decode_hex_literal(s: &str) -> Option<Vec<u8>> {
+        let hex_bytes = s.as_bytes();
+        let mut decoded_bytes = Vec::with_capacity((hex_bytes.len() + 1) / 2);
+
+        let start_idx = hex_bytes.len() % 2;
+        if start_idx > 0 {
+            // The first byte is formed of only one char.
+            decoded_bytes.push(Self::try_decode_hex_char(hex_bytes[0])?);
+        }
+
+        for i in (start_idx..hex_bytes.len()).step_by(2) {
+            let high = Self::try_decode_hex_char(hex_bytes[i])?;
+            let low = Self::try_decode_hex_char(hex_bytes[i + 1])?;
+            decoded_bytes.push(high << 4 | low);
+        }
+
+        Some(decoded_bytes)
+    }
+
+    /// Try to decode a byte from a hex char.
+    ///
+    /// None will be returned if the input char is hex-invalid.
+    const fn try_decode_hex_char(c: u8) -> Option<u8> {
+        match c {
+            b'A'..=b'F' => Some(c - b'A' + 10),
+            b'a'..=b'f' => Some(c - b'a' + 10),
+            b'0'..=b'9' => Some(c - b'0'),
+            _ => None,
+        }
+    }
+
     /// Optimize the filter expression and coerce data types.
     pub fn optimize_expr(&self, expr: Expr) -> Result<Expr> {
         let df_schema = Arc::new(DFSchema::try_from(self.schema.as_ref().clone())?);