Rust Union support

src/storage/store/struct_node_column.cpp

@@ -60,7 +60,7 @@ void StructNodeColumn::writeInternal(
 
 void StructNodeColumn::append(ColumnChunk* columnChunk, uint64_t nodeGroupIdx) {
     NodeColumn::append(columnChunk, nodeGroupIdx);
-    assert(columnChunk->getDataType().getLogicalTypeID() == LogicalTypeID::STRUCT);
+    assert(columnChunk->getDataType().getPhysicalType() == PhysicalTypeID::STRUCT);
     auto structColumnChunk = static_cast<StructColumnChunk*>(columnChunk);
     for (auto i = 0u; i < childColumns.size(); i++) {
         childColumns[i]->append(structColumnChunk->getChild(i), nodeGroupIdx);

tools/rust_api/include/kuzu_rs.h

@@ -42,7 +42,8 @@ std::unique_ptr<kuzu::common::LogicalType> create_logical_type_var_list(
 std::unique_ptr<kuzu::common::LogicalType> create_logical_type_fixed_list(
     std::unique_ptr<kuzu::common::LogicalType> childType, uint64_t numElements);
 std::unique_ptr<kuzu::common::LogicalType> create_logical_type_struct(
-    const rust::Vec<rust::String>& fieldNames, std::unique_ptr<TypeListBuilder> fieldTypes);
+    kuzu::common::LogicalTypeID typeID, const rust::Vec<rust::String>& fieldNames,
+    std::unique_ptr<TypeListBuilder> fieldTypes);
 std::unique_ptr<kuzu::common::LogicalType> create_logical_type_map(
     std::unique_ptr<kuzu::common::LogicalType> keyType,
     std::unique_ptr<kuzu::common::LogicalType> valueType);

tools/rust_api/src/ffi.rs

@@ -192,6 +192,7 @@ pub(crate) mod ffi {
             num_elements: u64,
         ) -> UniquePtr<LogicalType>;
         fn create_logical_type_struct(
+            type_id: LogicalTypeID,
             field_names: &Vec<String>,
             types: UniquePtr<TypeListBuilder>,
         ) -> UniquePtr<LogicalType>;

tools/rust_api/src/kuzu_rs.cpp

@@ -33,15 +33,15 @@ std::unique_ptr<LogicalType> create_logical_type_fixed_list(
         std::make_unique<FixedListTypeInfo>(std::move(childType), numElements));
 }
 
-std::unique_ptr<kuzu::common::LogicalType> create_logical_type_struct(
+std::unique_ptr<kuzu::common::LogicalType> create_logical_type_struct(LogicalTypeID typeID,
     const rust::Vec<rust::String>& fieldNames, std::unique_ptr<TypeListBuilder> fieldTypes) {
     std::vector<std::unique_ptr<StructField>> fields;
     for (auto i = 0u; i < fieldNames.size(); i++) {
         fields.push_back(std::make_unique<StructField>(
             std::string(fieldNames[i]), std::move(fieldTypes->types[i])));
     }
     return std::make_unique<LogicalType>(
-        LogicalTypeID::STRUCT, std::make_unique<kuzu::common::StructTypeInfo>(std::move(fields)));
+        typeID, std::make_unique<kuzu::common::StructTypeInfo>(std::move(fields)));
 }
 
 std::unique_ptr<kuzu::common::LogicalType> create_logical_type_map(

tools/rust_api/src/logical_type.rs

@@ -62,10 +62,14 @@ pub enum LogicalType {
     /// Correponds to [Value::Rel](crate::value::Value::Rel)
     Rel,
     RecursiveRel,
+    /// Correponds to [Value::Map](crate::value::Value::Map)
     Map {
         key_type: Box<LogicalType>,
         value_type: Box<LogicalType>,
     },
+    Union {
+        types: Vec<(String, LogicalType)>,
+    },
 }
 
 impl From<&ffi::Value> for LogicalType {
@@ -141,6 +145,18 @@ impl From<&ffi::LogicalType> for LogicalType {
                     value_type: Box::new(value_type),
                 }
             }
+            LogicalTypeID::UNION => {
+                let names = ffi::logical_type_get_struct_field_names(logical_type);
+                let types = ffi::logical_type_get_struct_field_types(logical_type);
+                LogicalType::Union {
+                    types: names
+                        .into_iter()
+                        // Skip the tag field
+                        .skip(1)
+                        .zip(types.into_iter().skip(1).map(Into::<LogicalType>::into))
+                        .collect(),
+                }
+            }
             // Should be unreachable, as cxx will check that the LogicalTypeID enum matches the one
             // on the C++ side.
             x => panic!("Unsupported type {:?}", x),
@@ -187,7 +203,18 @@ impl From<&LogicalType> for cxx::UniquePtr<ffi::LogicalType> {
                     names.push(name.clone());
                     builder.pin_mut().insert(typ.into());
                 }
-                ffi::create_logical_type_struct(&names, builder)
+                ffi::create_logical_type_struct(ffi::LogicalTypeID::STRUCT, &names, builder)
+            }
+            LogicalType::Union { types } => {
+                let mut builder = ffi::create_type_list();
+                let mut names = vec![];
+                names.push("tag".to_string());
+                builder.pin_mut().insert((&LogicalType::Int64).into());
+                for (name, typ) in types {
+                    names.push(name.clone());
+                    builder.pin_mut().insert(typ.into());
+                }
+                ffi::create_logical_type_struct(ffi::LogicalTypeID::UNION, &names, builder)
             }
             LogicalType::Map {
                 key_type,
@@ -227,6 +254,7 @@ impl LogicalType {
             LogicalType::Rel => LogicalTypeID::REL,
             LogicalType::RecursiveRel => LogicalTypeID::RECURSIVE_REL,
             LogicalType::Map { .. } => LogicalTypeID::MAP,
+            LogicalType::Union { .. } => LogicalTypeID::UNION,
         }
     }
 }

tools/rust_api/src/value.rs

@@ -188,7 +188,7 @@ impl From<(u64, u64)> for InternalID {
 
 /// Data types supported by Kùzu
 ///
-/// Also see <https://kuzudb.com/docs/cypher/data-types/overview.html>
+/// Also see <https://kuzudb.com/docusaurus/cypher/data-types/overview.html>
 #[derive(Clone, Debug, PartialEq)]
 pub enum Value {
     Null(LogicalType),
@@ -206,33 +206,33 @@ pub enum Value {
     /// Stored internally as the number of days since 1970-01-01 as a 32-bit signed integer, which
     /// allows for a wider range of dates to be stored than can be represented by time::Date
     ///
-    /// <https://kuzudb.com/docs/cypher/data-types/date.html>
+    /// <https://kuzudb.com/docusaurus/cypher/data-types/date.html>
     Date(time::Date),
     /// May be signed or unsigned.
     ///
     /// Nanosecond precision of time::Duration (if available) will not be preserved when passed to
     /// queries, and results will always have at most microsecond precision.
     ///
-    /// <https://kuzudb.com/docs/cypher/data-types/interval.html>
+    /// <https://kuzudb.com/docusaurus/cypher/data-types/interval.html>
     Interval(time::Duration),
     /// Stored internally as the number of microseconds since 1970-01-01
     /// Nanosecond precision of SystemTime (if available) will not be preserved when used.
     ///
-    /// <https://kuzudb.com/docs/cypher/data-types/timestamp.html>
+    /// <https://kuzudb.com/docusaurus/cypher/data-types/timestamp.html>
     Timestamp(time::OffsetDateTime),
     InternalID(InternalID),
-    /// <https://kuzudb.com/docs/cypher/data-types/string.html>
+    /// <https://kuzudb.com/docusaurus/cypher/data-types/string.html>
     String(String),
     Blob(Vec<u8>),
     // TODO: Enforce type of contents
     // LogicalType is necessary so that we can pass the correct type to the C++ API if the list is empty.
     /// These must contain elements which are all the given type.
-    /// <https://kuzudb.com/docs/cypher/data-types/list.html>
+    /// <https://kuzudb.com/docusaurus/cypher/data-types/list.html>
     VarList(LogicalType, Vec<Value>),
     /// These must contain elements which are all the same type.
-    /// <https://kuzudb.com/docs/cypher/data-types/list.html>
+    /// <https://kuzudb.com/docusaurus/cypher/data-types/list.html>
     FixedList(LogicalType, Vec<Value>),
-    /// <https://kuzudb.com/docs/cypher/data-types/struct.html>
+    /// <https://kuzudb.com/docusaurus/cypher/data-types/struct.html>
     Struct(Vec<(String, Value)>),
     Node(NodeVal),
     Rel(RelVal),
@@ -244,7 +244,13 @@ pub enum Value {
         /// Sequence of Rels which make up the RecursiveRel
         rels: Vec<RelVal>,
     },
+    /// <https://kuzudb.com/docusaurus/cypher/data-types/map>
     Map((LogicalType, LogicalType), Vec<(Value, Value)>),
+    /// <https://kuzudb.com/docusaurus/cypher/data-types/union>
+    Union {
+        types: Vec<(String, LogicalType)>,
+        value: Box<Value>,
+    },
 }
 
 fn display_list<T: std::fmt::Display>(f: &mut fmt::Formatter<'_>, list: &Vec<T>) -> fmt::Result {
@@ -312,6 +318,7 @@ impl std::fmt::Display for Value {
                 display_list(f, rels)?;
                 write!(f, "}}")
             }
+            Value::Union { types: _, value } => write!(f, "{value}"),
         }
     }
 }
@@ -360,6 +367,9 @@ impl From<&Value> for LogicalType {
                 key_type: Box::new(key_type.clone()),
                 value_type: Box::new(value_type.clone()),
             },
+            Value::Union { types, value: _ } => LogicalType::Union {
+                types: types.clone(),
+            },
         }
     }
 }
@@ -542,6 +552,19 @@ impl TryFrom<&ffi::Value> for Value {
                     rels: rels.collect(),
                 })
             }
+            LogicalTypeID::UNION => {
+                let types =
+                    if let LogicalType::Union { types } = ffi::value_get_data_type(value).into() {
+                        types
+                    } else {
+                        unreachable!()
+                    };
+                let value: Value = ffi::value_get_child(value, 0).try_into()?;
+                Ok(Value::Union {
+                    types,
+                    value: Box::new(value),
+                })
+            }
             // TODO(bmwinger): Better error message for types which are unsupported
             x => panic!("Unsupported type {:?}", x),
         }
@@ -673,6 +696,15 @@ impl TryInto<cxx::UniquePtr<ffi::Value>> for Value {
             Value::RecursiveRel { .. } => {
                 Err(crate::Error::ReadOnlyType(LogicalType::RecursiveRel))
             }
+            Value::Union { types, value } => {
+                let mut builder = ffi::create_list();
+                builder.pin_mut().insert((*value).try_into()?);
+
+                Ok(ffi::get_list_value(
+                    (&LogicalType::Union { types }).into(),
+                    builder,
+                ))
+            }
         }
     }
 }
@@ -870,6 +902,7 @@ mod tests {
         convert_rel_type: LogicalType::Rel,
         convert_recursive_rel_type: LogicalType::RecursiveRel,
         convert_map_type: LogicalType::Map { key_type: Box::new(LogicalType::Interval), value_type: Box::new(LogicalType::Rel) },
+        convert_union_type: LogicalType::Union { types: vec![("Num".to_string(), LogicalType::Int8), ("duration".to_string(), LogicalType::Interval), ("string".to_string(), LogicalType::String)] },
     }
 
     value_tests! {
@@ -898,6 +931,10 @@ mod tests {
         convert_struct: Value::Struct(vec![("NAME".to_string(), "Alice".into()), ("AGE".to_string(), 25.into())]),
         convert_internal_id: Value::InternalID(InternalID { table_id: 0, offset: 0 }),
         convert_map: Value::Map((LogicalType::String, LogicalType::Int64), vec![(Value::String("key".to_string()), Value::Int64(24))]),
+        convert_union: Value::Union {
+            types: vec![("Num".to_string(), LogicalType::Int8), ("duration".to_string(), LogicalType::Interval)],
+            value: Box::new(Value::Int8(-127))
+        },
     }
 
     display_tests! {
@@ -926,6 +963,10 @@ mod tests {
         display_internal_id: Value::InternalID(InternalID { table_id: 0, offset: 0 }),
         // Node and Rel Cannot be easily created on the C++ side
         display_map: Value::Map((LogicalType::String, LogicalType::Int64), vec![(Value::String("key".to_string()), Value::Int64(24))]),
+        display_union: Value::Union {
+            types: vec![("Num".to_string(), LogicalType::Int8), ("duration".to_string(), LogicalType::Interval)],
+            value: Box::new(Value::Int8(-127))
+        },
     }
 
     database_tests! {
@@ -934,6 +975,10 @@ mod tests {
         // db_var_list_int: Value::VarList(LogicalType::Int64, vec![0i64.into(), 1i64.into(), 2i64.into()]), "INT64[]",
         // db_map: Value::Map((LogicalType::String, LogicalType::Int64), vec![(Value::String("key".to_string()), Value::Int64(24))]), "MAP(STRING,INT64)",
         // db_fixed_list: Value::FixedList(LogicalType::Int64, vec![1i64.into(), 2i64.into(), 3i64.into()]), "INT64[3]",
+        // db_union: Value::Union {
+        //    types: vec![("Num".to_string(), LogicalType::Int8), ("duration".to_string(), LogicalType::Interval)],
+        //    value: Box::new(Value::Int8(-127))
+        // }, "UNION(Num INT8, duration INTERVAL)",
         db_struct:
            Value::Struct(vec![("item".to_string(), "Knife".into()), ("count".to_string(), 1.into())]),
            "STRUCT(item STRING, count INT32)",
@@ -1138,4 +1183,52 @@ mod tests {
         temp_dir.close()?;
         Ok(())
     }
+
+    #[test]
+    /// Tests that passing the values through the database returns what we put in
+    fn test_union() -> Result<()> {
+        use std::fs::File;
+        use std::io::Write;
+        let temp_dir = tempfile::tempdir()?;
+        let db = Database::new(temp_dir.path(), SystemConfig::default())?;
+        let conn = Connection::new(&db)?;
+        conn.query(
+            "CREATE NODE TABLE demo(a SERIAL, b UNION(num INT64, str STRING), PRIMARY KEY(a));",
+        )?;
+        let mut file = File::create(temp_dir.path().join("demo.csv"))?;
+        file.write_all(b"1\naa\n")?;
+        conn.query(&format!(
+            "COPY demo from '{}/demo.csv';",
+            // Use forward-slashes instead of backslashes on windows, as thmay not be supported by
+            // the query parser
+            temp_dir.path().display().replace("\\", "/")
+        ))?;
+        let result = conn.query("MATCH (d:demo) RETURN d.b;")?;
+        let types = vec![
+            ("num".to_string(), LogicalType::Int64),
+            ("str".to_string(), LogicalType::String),
+        ];
+        assert_eq!(
+            result.get_column_data_types(),
+            vec![LogicalType::Union {
+                types: types.clone()
+            }],
+        );
+        let results: Vec<Value> = result.map(|mut x| x.pop().unwrap()).collect();
+        assert_eq!(
+            results,
+            vec![
+                Value::Union {
+                    types: types.clone(),
+                    value: Box::new(Value::Int64(1))
+                },
+                Value::Union {
+                    types: types.clone(),
+                    value: Box::new(Value::String("aa".to_string()))
+                },
+            ]
+        );
+        temp_dir.close()?;
+        Ok(())
+    }
 }