Add levenshtein and hamming_distance functions (#60412)

Related Issue: #48203
Related PR: #57144 (reference)
Problem Summary: support levenshtein (Hive) and hamming_distance
(Trino/Presto).

Author: KazeBox33

be/src/exprs/function/function_hamming_distance.cpp

@@ -0,0 +1,320 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#include <algorithm>
+#include <vector>
+
+#include "common/status.h"
+#include "core/column/column_nullable.h"
+#include "core/column/column_string.h"
+#include "core/data_type/data_type_number.h"
+#include "core/string_ref.h"
+#include "exprs/function/simple_function_factory.h"
+#include "util/simd/vstring_function.h"
+
+namespace doris {
+
+class FunctionHammingDistance : public IFunction {
+public:
+    using ResultDataType = DataTypeInt64;
+    using ResultPaddedPODArray = PaddedPODArray<Int64>;
+    using ResultColumnType = ColumnVector<ResultDataType::PType>;
+
+    static constexpr auto name = "hamming_distance";
+
+    static FunctionPtr create() { return std::make_shared<FunctionHammingDistance>(); }
+
+    String get_name() const override { return name; }
+    size_t get_number_of_arguments() const override { return 2; }
+
+    DataTypePtr get_return_type_impl(const DataTypes& arguments) const override {
+        const bool has_nullable = std::ranges::any_of(
+                arguments, [](const DataTypePtr& type) { return type->is_nullable(); });
+        if (has_nullable) {
+            return make_nullable(std::make_shared<ResultDataType>());
+        }
+        return std::make_shared<ResultDataType>();
+    }
+
+    bool use_default_implementation_for_nulls() const override { return false; }
+
+    Status execute_impl(FunctionContext* /*context*/, Block& block, const ColumnNumbers& arguments,
+                        uint32_t result, size_t input_rows_count) const override {
+        const auto& [left_col, left_const] =
+                unpack_if_const(block.get_by_position(arguments[0]).column);
+        const auto& [right_col, right_const] =
+                unpack_if_const(block.get_by_position(arguments[1]).column);
+
+        const auto* left_nullable = check_and_get_column<ColumnNullable>(left_col.get());
+        const auto* right_nullable = check_and_get_column<ColumnNullable>(right_col.get());
+
+        const IColumn* left_nested =
+                left_nullable ? &left_nullable->get_nested_column() : left_col.get();
+        const IColumn* right_nested =
+                right_nullable ? &right_nullable->get_nested_column() : right_col.get();
+
+        const auto* left_str_col = assert_cast<const ColumnString*>(left_nested);
+        const auto* right_str_col = assert_cast<const ColumnString*>(right_nested);
+
+        auto res_col = ResultColumnType::create(input_rows_count);
+        auto& res_data = res_col->get_data();
+
+        const NullMap* left_null_map =
+                left_nullable ? &left_nullable->get_null_map_data() : nullptr;
+        const NullMap* right_null_map =
+                right_nullable ? &right_nullable->get_null_map_data() : nullptr;
+        const bool has_nullable = left_null_map != nullptr || right_null_map != nullptr;
+
+        if (!has_nullable) {
+            if (left_const) {
+                RETURN_IF_ERROR(scalar_vector(left_str_col->get_data_at(0).trim_tail_padding_zero(),
+                                              *right_str_col, res_data));
+            } else if (right_const) {
+                RETURN_IF_ERROR(vector_scalar(
+                        *left_str_col, right_str_col->get_data_at(0).trim_tail_padding_zero(),
+                        res_data));
+            } else {
+                RETURN_IF_ERROR(vector_vector(*left_str_col, *right_str_col, res_data));
+            }
+            block.replace_by_position(result, std::move(res_col));
+            return Status::OK();
+        }
+
+        auto null_col = ColumnUInt8::create(input_rows_count, 0);
+        auto& null_map = null_col->get_data();
+        if (left_const) {
+            if (left_null_map && (*left_null_map)[0]) {
+                std::fill(null_map.begin(), null_map.end(), 1);
+                block.replace_by_position(
+                        result, ColumnNullable::create(std::move(res_col), std::move(null_col)));
+                return Status::OK();
+            }
+
+            const auto left = left_str_col->get_data_at(0).trim_tail_padding_zero();
+            RETURN_IF_ERROR(scalar_vector_nullable(left, *right_str_col, right_null_map, res_data,
+                                                   null_map));
+        } else if (right_const) {
+            if (right_null_map && (*right_null_map)[0]) {
+                std::fill(null_map.begin(), null_map.end(), 1);
+                block.replace_by_position(
+                        result, ColumnNullable::create(std::move(res_col), std::move(null_col)));
+                return Status::OK();
+            }
+
+            RETURN_IF_ERROR(vector_scalar_nullable(
+                    *left_str_col, right_str_col->get_data_at(0).trim_tail_padding_zero(),
+                    left_null_map, res_data, null_map));
+        } else {
+            for (size_t i = 0; i < input_rows_count; ++i) {
+                const bool left_is_null = left_null_map && (*left_null_map)[i];
+                const bool right_is_null = right_null_map && (*right_null_map)[i];
+                if (left_is_null || right_is_null) {
+                    null_map[i] = 1;
+                    res_data[i] = 0;
+                    continue;
+                }
+
+                RETURN_IF_ERROR(hamming_distance(
+                        left_str_col->get_data_at(i).trim_tail_padding_zero(),
+                        right_str_col->get_data_at(i).trim_tail_padding_zero(), res_data[i], i));
+            }
+        }
+
+        block.replace_by_position(result,
+                                  ColumnNullable::create(std::move(res_col), std::move(null_col)));
+        return Status::OK();
+    }
+
+private:
+    static Status vector_vector(const ColumnString& lcol, const ColumnString& rcol,
+                                ResultPaddedPODArray& res) {
+        DCHECK_EQ(lcol.size(), rcol.size());
+
+        const size_t size = lcol.size();
+        res.resize(size);
+        std::vector<size_t> left_offsets;
+        std::vector<size_t> right_offsets;
+        for (size_t i = 0; i < size; ++i) {
+            const auto left = lcol.get_data_at(i).trim_tail_padding_zero();
+            const auto right = rcol.get_data_at(i).trim_tail_padding_zero();
+            RETURN_IF_ERROR(hamming_distance_with_offsets(
+                    left, left_offsets, false, simd::VStringFunctions::is_ascii(left), right,
+                    right_offsets, false, simd::VStringFunctions::is_ascii(right), res[i], i));
+        }
+        return Status::OK();
+    }
+
+    static Status vector_scalar(const ColumnString& lcol, const StringRef& rdata,
+                                ResultPaddedPODArray& res) {
+        const size_t size = lcol.size();
+        res.resize(size);
+        const bool right_ascii = simd::VStringFunctions::is_ascii(rdata);
+        std::vector<size_t> right_offsets;
+        simd::VStringFunctions::get_utf8_char_offsets(rdata, right_offsets);
+        std::vector<size_t> left_offsets;
+        for (size_t i = 0; i < size; ++i) {
+            const auto left = lcol.get_data_at(i).trim_tail_padding_zero();
+            RETURN_IF_ERROR(hamming_distance_with_offsets(
+                    left, left_offsets, false, simd::VStringFunctions::is_ascii(left), rdata,
+                    right_offsets, true, right_ascii, res[i], i));
+        }
+        return Status::OK();
+    }
+
+    static Status scalar_vector(const StringRef& ldata, const ColumnString& rcol,
+                                ResultPaddedPODArray& res) {
+        const size_t size = rcol.size();
+        res.resize(size);
+        const bool left_ascii = simd::VStringFunctions::is_ascii(ldata);
+        std::vector<size_t> left_offsets;
+        simd::VStringFunctions::get_utf8_char_offsets(ldata, left_offsets);
+        std::vector<size_t> right_offsets;
+        for (size_t i = 0; i < size; ++i) {
+            const auto right = rcol.get_data_at(i).trim_tail_padding_zero();
+            RETURN_IF_ERROR(hamming_distance_with_offsets(
+                    ldata, left_offsets, true, left_ascii, right, right_offsets, false,
+                    simd::VStringFunctions::is_ascii(right), res[i], i));
+        }
+        return Status::OK();
+    }
+
+    static Status vector_scalar_nullable(const ColumnString& lcol, const StringRef& rdata,
+                                         const NullMap* left_null_map, ResultPaddedPODArray& res,
+                                         NullMap& null_map) {
+        const size_t size = lcol.size();
+        res.resize(size);
+        const bool right_ascii = simd::VStringFunctions::is_ascii(rdata);
+        std::vector<size_t> right_offsets;
+        simd::VStringFunctions::get_utf8_char_offsets(rdata, right_offsets);
+        std::vector<size_t> left_offsets;
+        for (size_t i = 0; i < size; ++i) {
+            if (left_null_map && (*left_null_map)[i]) {
+                null_map[i] = 1;
+                res[i] = 0;
+                continue;
+            }
+
+            const auto left = lcol.get_data_at(i).trim_tail_padding_zero();
+            RETURN_IF_ERROR(hamming_distance_with_offsets(
+                    left, left_offsets, false, simd::VStringFunctions::is_ascii(left), rdata,
+                    right_offsets, true, right_ascii, res[i], i));
+        }
+        return Status::OK();
+    }
+
+    static Status scalar_vector_nullable(const StringRef& ldata, const ColumnString& rcol,
+                                         const NullMap* right_null_map, ResultPaddedPODArray& res,
+                                         NullMap& null_map) {
+        const size_t size = rcol.size();
+        res.resize(size);
+        const bool left_ascii = simd::VStringFunctions::is_ascii(ldata);
+        std::vector<size_t> left_offsets;
+        simd::VStringFunctions::get_utf8_char_offsets(ldata, left_offsets);
+        std::vector<size_t> right_offsets;
+        for (size_t i = 0; i < size; ++i) {
+            if (right_null_map && (*right_null_map)[i]) {
+                null_map[i] = 1;
+                res[i] = 0;
+                continue;
+            }
+
+            const auto right = rcol.get_data_at(i).trim_tail_padding_zero();
+            RETURN_IF_ERROR(hamming_distance_with_offsets(
+                    ldata, left_offsets, true, left_ascii, right, right_offsets, false,
+                    simd::VStringFunctions::is_ascii(right), res[i], i));
+        }
+        return Status::OK();
+    }
+
+    static Status hamming_distance_ascii(const StringRef& left, const StringRef& right,
+                                         Int64& result, size_t row) {
+        if (left.size != right.size) {
+            return Status::InvalidArgument(
+                    "hamming_distance requires strings of the same length at row {}", row);
+        }
+
+        Int64 distance = 0;
+        for (size_t i = 0; i < left.size; ++i) {
+            distance += static_cast<Int64>(left.data[i] != right.data[i]);
+        }
+        result = distance;
+        return Status::OK();
+    }
+
+    static Status hamming_distance_utf8(const StringRef& left,
+                                        const std::vector<size_t>& left_offsets,
+                                        const StringRef& right,
+                                        const std::vector<size_t>& right_offsets, Int64& result,
+                                        size_t row) {
+        if (left_offsets.size() != right_offsets.size()) {
+            return Status::InvalidArgument(
+                    "hamming_distance requires strings of the same length at row {}", row);
+        }
+
+        Int64 distance = 0;
+        const size_t len = left_offsets.size();
+        for (size_t i = 0; i + 1 < len; ++i) {
+            const size_t left_off = left_offsets[i];
+            const size_t left_next = left_offsets[i + 1];
+            const size_t right_off = right_offsets[i];
+            const size_t right_next = right_offsets[i + 1];
+            distance += static_cast<Int64>(!simd::VStringFunctions::utf8_char_equal(
+                    left, left_off, left_next, right, right_off, right_next));
+        }
+        if (len > 0) {
+            const size_t left_off = left_offsets[len - 1];
+            const size_t right_off = right_offsets[len - 1];
+            distance += static_cast<Int64>(!simd::VStringFunctions::utf8_char_equal(
+                    left, left_off, left.size, right, right_off, right.size));
+        }
+
+        result = distance;
+        return Status::OK();
+    }
+
+    static Status hamming_distance_with_offsets(
+            const StringRef& left, std::vector<size_t>& left_offsets, bool left_offsets_ready,
+            bool left_ascii, const StringRef& right, std::vector<size_t>& right_offsets,
+            bool right_offsets_ready, bool right_ascii, Int64& result, size_t row) {
+        if (left_ascii && right_ascii) {
+            return hamming_distance_ascii(left, right, result, row);
+        }
+
+        if (!left_offsets_ready) {
+            simd::VStringFunctions::get_utf8_char_offsets(left, left_offsets);
+        }
+        if (!right_offsets_ready) {
+            simd::VStringFunctions::get_utf8_char_offsets(right, right_offsets);
+        }
+        return hamming_distance_utf8(left, left_offsets, right, right_offsets, result, row);
+    }
+
+    static Status hamming_distance(const StringRef& left, const StringRef& right, Int64& result,
+                                   size_t row) {
+        std::vector<size_t> left_offsets;
+        std::vector<size_t> right_offsets;
+        return hamming_distance_with_offsets(
+                left, left_offsets, false, simd::VStringFunctions::is_ascii(left), right,
+                right_offsets, false, simd::VStringFunctions::is_ascii(right), result, row);
+    }
+};
+
+void register_function_hamming_distance(SimpleFunctionFactory& factory) {
+    factory.register_function<FunctionHammingDistance>();
+}
+
+} // namespace doris