From 6a8729c5e572146981387275aec62d6b8c0e15ac Mon Sep 17 00:00:00 2001
From: wangwei <1261385937@qq.com>
Date: Fri, 27 Oct 2023 11:26:17 +0800
Subject: [PATCH 1/3] add Reserve for column. Optimize large block insertion

---
 clickhouse/columns/array.cpp          |  6 ++++++
 clickhouse/columns/array.h            |  3 +++
 clickhouse/columns/column.h           |  3 +++
 clickhouse/columns/date.cpp           |  5 +++++
 clickhouse/columns/date.h             | 26 +++++++++++++++-----------
 clickhouse/columns/decimal.cpp        |  5 +++++
 clickhouse/columns/decimal.h          |  2 ++
 clickhouse/columns/enum.cpp           |  6 ++++++
 clickhouse/columns/enum.h             |  3 +++
 clickhouse/columns/geo.cpp            |  6 ++++++
 clickhouse/columns/geo.h              |  3 +++
 clickhouse/columns/ip4.cpp            |  5 +++++
 clickhouse/columns/ip4.h              |  3 +++
 clickhouse/columns/ip6.cpp            |  5 +++++
 clickhouse/columns/ip6.h              |  3 +++
 clickhouse/columns/lowcardinality.cpp |  6 ++++++
 clickhouse/columns/lowcardinality.h   |  3 +++
 clickhouse/columns/map.cpp            |  5 +++++
 clickhouse/columns/map.h              |  3 +++
 clickhouse/columns/nothing.h          |  3 +++
 clickhouse/columns/nullable.cpp       |  6 ++++++
 clickhouse/columns/nullable.h         |  3 +++
 clickhouse/columns/numeric.h          |  6 +++---
 clickhouse/columns/string.cpp         |  7 +++++++
 clickhouse/columns/string.h           |  6 ++++++
 clickhouse/columns/tuple.cpp          |  5 +++++
 clickhouse/columns/tuple.h            |  3 +++
 clickhouse/columns/uuid.cpp           |  5 +++++
 clickhouse/columns/uuid.h             |  3 +++
 29 files changed, 134 insertions(+), 14 deletions(-)

diff --git a/clickhouse/columns/array.cpp b/clickhouse/columns/array.cpp
index 5e5e72e7..cf088186 100644
--- a/clickhouse/columns/array.cpp
+++ b/clickhouse/columns/array.cpp
@@ -52,6 +52,12 @@ ColumnRef ColumnArray::CloneEmpty() const {
     return std::make_shared<ColumnArray>(data_->CloneEmpty());
 }
 
+void ColumnArray::Reserve(size_t new_cap)
+{
+    data_->Reserve(new_cap);
+    offsets_->Reserve(new_cap);
+}
+
 void ColumnArray::Append(ColumnRef column) {
     if (auto col = column->As<ColumnArray>()) {
         for (size_t i = 0; i < col->Size(); ++i) {
diff --git a/clickhouse/columns/array.h b/clickhouse/columns/array.h
index 0ea33d5a..ea51c778 100644
--- a/clickhouse/columns/array.h
+++ b/clickhouse/columns/array.h
@@ -47,6 +47,9 @@ class ColumnArray : public Column {
     }
 
 public:
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends content of given column to the end of current one.
     void Append(ColumnRef column) override;
 
diff --git a/clickhouse/columns/column.h b/clickhouse/columns/column.h
index b54cbdee..475df89a 100644
--- a/clickhouse/columns/column.h
+++ b/clickhouse/columns/column.h
@@ -52,6 +52,9 @@ class Column : public std::enable_shared_from_this<Column> {
     /// Appends content of given column to the end of current one.
     virtual void Append(ColumnRef column) = 0;
 
+    /// Increase the capacity of the column for large block insertion.
+    virtual void Reserve(size_t new_cap) = 0;
+
     /// Template method to load column data from input stream. It'll call LoadPrefix and LoadBody.
     /// Should be called only once from the client. Derived classes should not call it.
     bool Load(InputStream* input, size_t rows);
diff --git a/clickhouse/columns/date.cpp b/clickhouse/columns/date.cpp
index c3476c7f..132c6fc7 100644
--- a/clickhouse/columns/date.cpp
+++ b/clickhouse/columns/date.cpp
@@ -303,6 +303,11 @@ std::string ColumnDateTime64::Timezone() const {
     return type_->As<DateTime64Type>()->Timezone();
 }
 
+void ColumnDateTime64::Reserve(size_t new_cap)
+{
+    data_->Reserve(new_cap);
+}
+
 void ColumnDateTime64::Append(ColumnRef column) {
     if (auto col = column->As<ColumnDateTime64>()) {
         data_->Append(col->data_);
diff --git a/clickhouse/columns/date.h b/clickhouse/columns/date.h
index c6e32234..bf501723 100644
--- a/clickhouse/columns/date.h
+++ b/clickhouse/columns/date.h
@@ -34,8 +34,8 @@ class ColumnDate : public Column {
     /// Get Raw Vector Contents
     std::vector<uint16_t>& GetWritableData();
 
-    /// Increase the capacity of the column
-    void Reserve(size_t new_cap);
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
 
     /// Returns the capacity of the column
     size_t Capacity() const;
@@ -79,9 +79,6 @@ class ColumnDate32 : public Column {
     /// The implementation is fundamentally wrong, ignores timezones, leap years and daylight saving.
     std::time_t At(size_t n) const;
 
-    /// Appends content of given column to the end of current one.
-    void Append(ColumnRef column) override;
-
     inline std::time_t operator [] (size_t n) const { return At(n); }
 
     /// Do append data as is -- number of day in Unix epoch (32bit signed), no conversions performed.
@@ -91,12 +88,16 @@ class ColumnDate32 : public Column {
     /// Get Raw Vector Contents
     std::vector<int32_t>& GetWritableData();
 
-    /// Increase the capacity of the column
-    void Reserve(size_t new_cap);
-
     /// Returns the capacity of the column
     size_t Capacity() const;
 
+public:
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
+    /// Appends content of given column to the end of current one.
+    void Append(ColumnRef column) override;
+
     /// Loads column data from input stream.
     bool LoadBody(InputStream* input, size_t rows) override;
 
@@ -148,13 +149,13 @@ class ColumnDateTime : public Column {
     /// Get Raw Vector Contents
     std::vector<uint32_t>& GetWritableData();
 
-    /// Increase the capacity of the column
-    void Reserve(size_t new_cap);
-
     /// Returns the capacity of the column
     size_t Capacity() const;
 
 public:
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends content of given column to the end of current one.
     void Append(ColumnRef column) override;
 
@@ -205,6 +206,9 @@ class ColumnDateTime64 : public Column {
     std::string Timezone() const;
 
 public:
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends content of given column to the end of current one.
     void Append(ColumnRef column) override;
 
diff --git a/clickhouse/columns/decimal.cpp b/clickhouse/columns/decimal.cpp
index d44dc0c0..37de8647 100644
--- a/clickhouse/columns/decimal.cpp
+++ b/clickhouse/columns/decimal.cpp
@@ -191,6 +191,11 @@ Int128 ColumnDecimal::At(size_t i) const {
     }
 }
 
+void ColumnDecimal::Reserve(size_t new_cap)
+{
+    data_->Reserve(new_cap);
+}
+
 void ColumnDecimal::Append(ColumnRef column) {
     if (auto col = column->As<ColumnDecimal>()) {
         data_->Append(col->data_);
diff --git a/clickhouse/columns/decimal.h b/clickhouse/columns/decimal.h
index 4b09553a..aa499a12 100644
--- a/clickhouse/columns/decimal.h
+++ b/clickhouse/columns/decimal.h
@@ -21,6 +21,8 @@ class ColumnDecimal : public Column {
     inline auto operator[](size_t i) const { return At(i); }
 
 public:
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
     void Append(ColumnRef column) override;
     bool LoadBody(InputStream* input, size_t rows) override;
     void SaveBody(OutputStream* output) override;
diff --git a/clickhouse/columns/enum.cpp b/clickhouse/columns/enum.cpp
index c84d9847..c6729e64 100644
--- a/clickhouse/columns/enum.cpp
+++ b/clickhouse/columns/enum.cpp
@@ -68,6 +68,12 @@ void ColumnEnum<T>::SetNameAt(size_t n, const std::string& name) {
     data_.at(n) = static_cast<T>(type_->As<EnumType>()->GetEnumValue(name));
 }
 
+template<typename T>
+void ColumnEnum<T>::Reserve(size_t new_cap)
+{
+    data_.reserve(new_cap);
+}
+
 template <typename T>
 void ColumnEnum<T>::Append(ColumnRef column) {
     if (auto col = column->As<ColumnEnum<T>>()) {
diff --git a/clickhouse/columns/enum.h b/clickhouse/columns/enum.h
index 1d962751..43900f6c 100644
--- a/clickhouse/columns/enum.h
+++ b/clickhouse/columns/enum.h
@@ -30,6 +30,9 @@ class ColumnEnum : public Column {
     void SetNameAt(size_t n, const std::string& name);
 
 public:
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends content of given column to the end of current one.
     void Append(ColumnRef column) override;
 
diff --git a/clickhouse/columns/geo.cpp b/clickhouse/columns/geo.cpp
index e618fbe5..b7bd2fc4 100644
--- a/clickhouse/columns/geo.cpp
+++ b/clickhouse/columns/geo.cpp
@@ -54,6 +54,12 @@ const typename ColumnGeo<NestedColumnType, type_code>::ValueType ColumnGeo<Neste
     return data_->At(n);
 }
 
+template<typename NestedColumnType, Type::Code type_code>
+void ColumnGeo<NestedColumnType, type_code>::Reserve(size_t new_cap)
+{
+    data_->Reserve(new_cap);
+}
+
 template <typename NestedColumnType, Type::Code type_code>
 void ColumnGeo<NestedColumnType, type_code>::Append(ColumnRef column) {
     if (auto col = column->template As<ColumnGeo>()) {
diff --git a/clickhouse/columns/geo.h b/clickhouse/columns/geo.h
index c3757f8a..1b129739 100644
--- a/clickhouse/columns/geo.h
+++ b/clickhouse/columns/geo.h
@@ -29,6 +29,9 @@ class ColumnGeo : public Column {
     inline const ValueType operator[](size_t n) const { return At(n); }
 
 public:
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends content of given column to the end of current one.
     void Append(ColumnRef column) override;
 
diff --git a/clickhouse/columns/ip4.cpp b/clickhouse/columns/ip4.cpp
index 5e7ca892..bc70ece6 100644
--- a/clickhouse/columns/ip4.cpp
+++ b/clickhouse/columns/ip4.cpp
@@ -74,6 +74,11 @@ std::string ColumnIPv4::AsString(size_t n) const {
     return ip_str;
 }
 
+void ColumnIPv4::Reserve(size_t new_cap)
+{
+    data_->Reserve(new_cap);
+}
+
 void ColumnIPv4::Append(ColumnRef column) {
     if (auto col = column->As<ColumnIPv4>()) {
         data_->Append(col->data_);
diff --git a/clickhouse/columns/ip4.h b/clickhouse/columns/ip4.h
index 103be527..2253e305 100644
--- a/clickhouse/columns/ip4.h
+++ b/clickhouse/columns/ip4.h
@@ -39,6 +39,9 @@ class ColumnIPv4 : public Column {
     std::string AsString(size_t n) const;
 
 public:
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends content of given column to the end of current one.
     void Append(ColumnRef column) override;
 
diff --git a/clickhouse/columns/ip6.cpp b/clickhouse/columns/ip6.cpp
index 838bcce0..1400ed01 100644
--- a/clickhouse/columns/ip6.cpp
+++ b/clickhouse/columns/ip6.cpp
@@ -65,6 +65,11 @@ in6_addr ColumnIPv6::operator [] (size_t n) const {
     return *reinterpret_cast<const in6_addr*>(data_->At(n).data());
 }
 
+void ColumnIPv6::Reserve(size_t new_cap)
+{
+    data_->Reserve(new_cap);
+}
+
 void ColumnIPv6::Append(ColumnRef column) {
     if (auto col = column->As<ColumnIPv6>()) {
         data_->Append(col->data_);
diff --git a/clickhouse/columns/ip6.h b/clickhouse/columns/ip6.h
index 74d8c1e1..41af0d58 100644
--- a/clickhouse/columns/ip6.h
+++ b/clickhouse/columns/ip6.h
@@ -35,6 +35,9 @@ class ColumnIPv6 : public Column {
     std::string AsString(size_t n) const;
 
 public:
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends content of given column to the end of current one.
     void Append(ColumnRef column) override;
 
diff --git a/clickhouse/columns/lowcardinality.cpp b/clickhouse/columns/lowcardinality.cpp
index c0c12319..95fce6a7 100644
--- a/clickhouse/columns/lowcardinality.cpp
+++ b/clickhouse/columns/lowcardinality.cpp
@@ -174,6 +174,12 @@ ColumnLowCardinality::ColumnLowCardinality(std::shared_ptr<ColumnNullable> dicti
 ColumnLowCardinality::~ColumnLowCardinality()
 {}
 
+void ColumnLowCardinality::Reserve(size_t new_cap)
+{
+    dictionary_column_->Reserve(new_cap);
+    index_column_->Reserve(new_cap);
+}
+
 void ColumnLowCardinality::Setup(ColumnRef dictionary_column) {
     AppendDefaultItem();
 
diff --git a/clickhouse/columns/lowcardinality.h b/clickhouse/columns/lowcardinality.h
index afadae22..17e3ce99 100644
--- a/clickhouse/columns/lowcardinality.h
+++ b/clickhouse/columns/lowcardinality.h
@@ -65,6 +65,9 @@ class ColumnLowCardinality : public Column {
 
     ~ColumnLowCardinality();
 
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends another LowCardinality column to the end of this one, updating dictionary.
     void Append(ColumnRef /*column*/) override;
 
diff --git a/clickhouse/columns/map.cpp b/clickhouse/columns/map.cpp
index 3f5616df..f98902c3 100644
--- a/clickhouse/columns/map.cpp
+++ b/clickhouse/columns/map.cpp
@@ -33,6 +33,11 @@ ColumnMap::ColumnMap(ColumnRef data)
     : Column(GetMapType(data->GetType())), data_(data->As<ColumnArray>()) {
 }
 
+void ColumnMap::Reserve(size_t new_cap)
+{
+    data_->Reserve(new_cap);
+}
+
 void ColumnMap::Clear() {
     data_->Clear();
 }
diff --git a/clickhouse/columns/map.h b/clickhouse/columns/map.h
index ac5dc0a7..4d644802 100644
--- a/clickhouse/columns/map.h
+++ b/clickhouse/columns/map.h
@@ -25,6 +25,9 @@ class ColumnMap : public Column {
      */
     explicit ColumnMap(ColumnRef data);
 
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends content of given column to the end of current one.
     void Append(ColumnRef column) override;
 
diff --git a/clickhouse/columns/nothing.h b/clickhouse/columns/nothing.h
index 0b28d572..8e1a4e30 100644
--- a/clickhouse/columns/nothing.h
+++ b/clickhouse/columns/nothing.h
@@ -26,6 +26,9 @@ class ColumnNothing : public Column {
     {
     }
 
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t) override {};
+
     /// Appends one element to the column.
     void Append(std::unique_ptr<void*>) { ++size_; }
 
diff --git a/clickhouse/columns/nullable.cpp b/clickhouse/columns/nullable.cpp
index dd863545..d02b7f2c 100644
--- a/clickhouse/columns/nullable.cpp
+++ b/clickhouse/columns/nullable.cpp
@@ -34,6 +34,12 @@ ColumnRef ColumnNullable::Nulls() const
        return nulls_;
 }
 
+void ColumnNullable::Reserve(size_t new_cap)
+{
+    nested_->Reserve(new_cap);
+    nulls_->Reserve(new_cap);
+}
+
 void ColumnNullable::Append(ColumnRef column) {
     if (auto col = column->As<ColumnNullable>()) {
         if (!col->nested_->Type()->IsEqual(nested_->Type())) {
diff --git a/clickhouse/columns/nullable.h b/clickhouse/columns/nullable.h
index c1924af0..1946e8b9 100644
--- a/clickhouse/columns/nullable.h
+++ b/clickhouse/columns/nullable.h
@@ -27,6 +27,9 @@ class ColumnNullable : public Column {
     ColumnRef Nulls() const;
 
 public:
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends content of given column to the end of current one.
     void Append(ColumnRef column) override;
 
diff --git a/clickhouse/columns/numeric.h b/clickhouse/columns/numeric.h
index 1cbcca9c..e2a7675e 100644
--- a/clickhouse/columns/numeric.h
+++ b/clickhouse/columns/numeric.h
@@ -19,6 +19,9 @@ class ColumnVector : public Column {
     explicit ColumnVector(const std::vector<T>& data);
     explicit ColumnVector(std::vector<T> && data);
 
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends one element to the end of column.
     void Append(const T& value);
 
@@ -33,9 +36,6 @@ class ColumnVector : public Column {
     /// Get Raw Vector Contents
     std::vector<T>& GetWritableData();
 
-    /// Increase the capacity of the column
-    void Reserve(size_t new_cap);
-
     /// Returns the capacity of the column
     size_t Capacity() const;
 
diff --git a/clickhouse/columns/string.cpp b/clickhouse/columns/string.cpp
index 62ec464b..07655967 100644
--- a/clickhouse/columns/string.cpp
+++ b/clickhouse/columns/string.cpp
@@ -190,6 +190,13 @@ ColumnString::ColumnString(std::vector<std::string>&& data)
 ColumnString::~ColumnString()
 {}
 
+void ColumnString::Reserve(size_t new_cap)
+{
+    items_.reserve(new_cap);
+    // 16 is arbitrary number, assumption that string values are about ~256 bytes long.
+    blocks_.reserve(std::max<size_t>(1, new_cap / 16));
+}
+
 void ColumnString::Append(std::string_view str) {
     if (blocks_.size() == 0 || blocks_.back().GetAvailable() < str.length()) {
         blocks_.emplace_back(std::max(DEFAULT_BLOCK_SIZE, str.size()));
diff --git a/clickhouse/columns/string.h b/clickhouse/columns/string.h
index aa78270e..6d6d5e77 100644
--- a/clickhouse/columns/string.h
+++ b/clickhouse/columns/string.h
@@ -27,6 +27,9 @@ class ColumnFixedString : public Column {
             Append(v);
     }
 
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t) override {};
+
     /// Appends one element to the column.
     void Append(std::string_view str);
 
@@ -84,6 +87,9 @@ class ColumnString : public Column {
     ColumnString& operator=(const ColumnString&) = delete;
     ColumnString(const ColumnString&) = delete;
 
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends one element to the column.
     void Append(std::string_view str);
 
diff --git a/clickhouse/columns/tuple.cpp b/clickhouse/columns/tuple.cpp
index 42dc6e63..24864063 100644
--- a/clickhouse/columns/tuple.cpp
+++ b/clickhouse/columns/tuple.cpp
@@ -20,6 +20,11 @@ size_t ColumnTuple::TupleSize() const {
     return columns_.size();
 }
 
+void ColumnTuple::Reserve(size_t new_cap)
+{
+    columns_.reserve(new_cap);
+}
+
 void ColumnTuple::Append(ColumnRef column) {
     if (!this->Type()->IsEqual(column->Type())) {
         throw ValidationError(
diff --git a/clickhouse/columns/tuple.h b/clickhouse/columns/tuple.h
index c9795565..ebc1b895 100644
--- a/clickhouse/columns/tuple.h
+++ b/clickhouse/columns/tuple.h
@@ -26,6 +26,9 @@ class ColumnTuple : public Column {
     }
 
 public:
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends content of given column to the end of current one.
     void Append(ColumnRef column) override;
 
diff --git a/clickhouse/columns/uuid.cpp b/clickhouse/columns/uuid.cpp
index 36a7229c..72d3d2b8 100644
--- a/clickhouse/columns/uuid.cpp
+++ b/clickhouse/columns/uuid.cpp
@@ -34,6 +34,11 @@ const UUID ColumnUUID::At(size_t n) const {
     return UUID(data_->At(n * 2), data_->At(n * 2 + 1));
 }
 
+void ColumnUUID::Reserve(size_t new_cap)
+{
+    data_->Reserve(new_cap);
+}
+
 void ColumnUUID::Append(ColumnRef column) {
     if (auto col = column->As<ColumnUUID>()) {
         data_->Append(col->data_);
diff --git a/clickhouse/columns/uuid.h b/clickhouse/columns/uuid.h
index 4f6c9192..ccd03f84 100644
--- a/clickhouse/columns/uuid.h
+++ b/clickhouse/columns/uuid.h
@@ -26,6 +26,9 @@ class ColumnUUID : public Column {
     inline const UUID operator [] (size_t n) const { return At(n); }
 
 public:
+    /// Increase the capacity of the column for large block insertion.
+    void Reserve(size_t new_cap) override;
+
     /// Appends content of given column to the end of current one.
     void Append(ColumnRef column) override;
 

From 79f311f781310dff47ed0c6968d611243acc7802 Mon Sep 17 00:00:00 2001
From: wangwei <1261385937@qq.com>
Date: Wed, 1 Nov 2023 16:13:03 +0800
Subject: [PATCH 2/3] code change for review

---
 clickhouse/columns/array.cpp          |  3 +--
 clickhouse/columns/decimal.cpp        |  3 +--
 clickhouse/columns/enum.cpp           |  3 +--
 clickhouse/columns/geo.cpp            |  3 +--
 clickhouse/columns/ip4.cpp            |  3 +--
 clickhouse/columns/ip6.cpp            |  3 +--
 clickhouse/columns/lowcardinality.cpp |  3 +--
 clickhouse/columns/map.cpp            |  3 +--
 clickhouse/columns/nullable.cpp       |  3 +--
 clickhouse/columns/string.cpp         | 17 +++++++++++------
 clickhouse/columns/string.h           |  2 +-
 clickhouse/columns/tuple.cpp          |  7 ++++---
 clickhouse/columns/uuid.cpp           |  3 +--
 13 files changed, 26 insertions(+), 30 deletions(-)

diff --git a/clickhouse/columns/array.cpp b/clickhouse/columns/array.cpp
index cf088186..1867d778 100644
--- a/clickhouse/columns/array.cpp
+++ b/clickhouse/columns/array.cpp
@@ -52,8 +52,7 @@ ColumnRef ColumnArray::CloneEmpty() const {
     return std::make_shared<ColumnArray>(data_->CloneEmpty());
 }
 
-void ColumnArray::Reserve(size_t new_cap)
-{
+void ColumnArray::Reserve(size_t new_cap) {
     data_->Reserve(new_cap);
     offsets_->Reserve(new_cap);
 }
diff --git a/clickhouse/columns/decimal.cpp b/clickhouse/columns/decimal.cpp
index 37de8647..2d214ecf 100644
--- a/clickhouse/columns/decimal.cpp
+++ b/clickhouse/columns/decimal.cpp
@@ -191,8 +191,7 @@ Int128 ColumnDecimal::At(size_t i) const {
     }
 }
 
-void ColumnDecimal::Reserve(size_t new_cap)
-{
+void ColumnDecimal::Reserve(size_t new_cap) {
     data_->Reserve(new_cap);
 }
 
diff --git a/clickhouse/columns/enum.cpp b/clickhouse/columns/enum.cpp
index c6729e64..43fab893 100644
--- a/clickhouse/columns/enum.cpp
+++ b/clickhouse/columns/enum.cpp
@@ -69,8 +69,7 @@ void ColumnEnum<T>::SetNameAt(size_t n, const std::string& name) {
 }
 
 template<typename T>
-void ColumnEnum<T>::Reserve(size_t new_cap)
-{
+void ColumnEnum<T>::Reserve(size_t new_cap) {
     data_.reserve(new_cap);
 }
 
diff --git a/clickhouse/columns/geo.cpp b/clickhouse/columns/geo.cpp
index b7bd2fc4..fa987732 100644
--- a/clickhouse/columns/geo.cpp
+++ b/clickhouse/columns/geo.cpp
@@ -55,8 +55,7 @@ const typename ColumnGeo<NestedColumnType, type_code>::ValueType ColumnGeo<Neste
 }
 
 template<typename NestedColumnType, Type::Code type_code>
-void ColumnGeo<NestedColumnType, type_code>::Reserve(size_t new_cap)
-{
+void ColumnGeo<NestedColumnType, type_code>::Reserve(size_t new_cap) {
     data_->Reserve(new_cap);
 }
 
diff --git a/clickhouse/columns/ip4.cpp b/clickhouse/columns/ip4.cpp
index bc70ece6..8790afb6 100644
--- a/clickhouse/columns/ip4.cpp
+++ b/clickhouse/columns/ip4.cpp
@@ -74,8 +74,7 @@ std::string ColumnIPv4::AsString(size_t n) const {
     return ip_str;
 }
 
-void ColumnIPv4::Reserve(size_t new_cap)
-{
+void ColumnIPv4::Reserve(size_t new_cap) {
     data_->Reserve(new_cap);
 }
 
diff --git a/clickhouse/columns/ip6.cpp b/clickhouse/columns/ip6.cpp
index 1400ed01..0d47b5e8 100644
--- a/clickhouse/columns/ip6.cpp
+++ b/clickhouse/columns/ip6.cpp
@@ -65,8 +65,7 @@ in6_addr ColumnIPv6::operator [] (size_t n) const {
     return *reinterpret_cast<const in6_addr*>(data_->At(n).data());
 }
 
-void ColumnIPv6::Reserve(size_t new_cap)
-{
+void ColumnIPv6::Reserve(size_t new_cap) {
     data_->Reserve(new_cap);
 }
 
diff --git a/clickhouse/columns/lowcardinality.cpp b/clickhouse/columns/lowcardinality.cpp
index 95fce6a7..19369d33 100644
--- a/clickhouse/columns/lowcardinality.cpp
+++ b/clickhouse/columns/lowcardinality.cpp
@@ -174,8 +174,7 @@ ColumnLowCardinality::ColumnLowCardinality(std::shared_ptr<ColumnNullable> dicti
 ColumnLowCardinality::~ColumnLowCardinality()
 {}
 
-void ColumnLowCardinality::Reserve(size_t new_cap)
-{
+void ColumnLowCardinality::Reserve(size_t new_cap) {
     dictionary_column_->Reserve(new_cap);
     index_column_->Reserve(new_cap);
 }
diff --git a/clickhouse/columns/map.cpp b/clickhouse/columns/map.cpp
index f98902c3..839b0668 100644
--- a/clickhouse/columns/map.cpp
+++ b/clickhouse/columns/map.cpp
@@ -33,8 +33,7 @@ ColumnMap::ColumnMap(ColumnRef data)
     : Column(GetMapType(data->GetType())), data_(data->As<ColumnArray>()) {
 }
 
-void ColumnMap::Reserve(size_t new_cap)
-{
+void ColumnMap::Reserve(size_t new_cap) {
     data_->Reserve(new_cap);
 }
 
diff --git a/clickhouse/columns/nullable.cpp b/clickhouse/columns/nullable.cpp
index d02b7f2c..23940c12 100644
--- a/clickhouse/columns/nullable.cpp
+++ b/clickhouse/columns/nullable.cpp
@@ -34,8 +34,7 @@ ColumnRef ColumnNullable::Nulls() const
        return nulls_;
 }
 
-void ColumnNullable::Reserve(size_t new_cap)
-{
+void ColumnNullable::Reserve(size_t new_cap) {
     nested_->Reserve(new_cap);
     nulls_->Reserve(new_cap);
 }
diff --git a/clickhouse/columns/string.cpp b/clickhouse/columns/string.cpp
index 07655967..791c2c6c 100644
--- a/clickhouse/columns/string.cpp
+++ b/clickhouse/columns/string.cpp
@@ -30,6 +30,10 @@ ColumnFixedString::ColumnFixedString(size_t n)
 {
 }
 
+void ColumnFixedString::Reserve(size_t new_cap) {
+    data_.reserve(string_size_ * new_cap);
+}
+
 void ColumnFixedString::Append(std::string_view str) {
     if (str.size() > string_size_) {
         throw ValidationError("Expected string of length not greater than "
@@ -45,8 +49,10 @@ void ColumnFixedString::Append(std::string_view str) {
 
     data_.insert(data_.size(), str);
     // Pad up to string_size_ with zeroes.
-    const auto padding_size = string_size_ - str.size();
-    data_.resize(data_.size() + padding_size, char(0));
+    if (str.size() < string_size_) {
+        const auto padding_size = string_size_ - str.size();
+        data_.resize(data_.size() + padding_size, char(0));
+    }
 }
 
 void ColumnFixedString::Clear() {
@@ -160,8 +166,8 @@ ColumnString::ColumnString(size_t element_count)
     : Column(Type::CreateString())
 {
     items_.reserve(element_count);
-    // 100 is arbitrary number, assumption that string values are about ~40 bytes long.
-    blocks_.reserve(std::max<size_t>(1, element_count / 100));
+    // 16 is arbitrary number, assumption that string values are about ~256 bytes long.
+    blocks_.reserve(std::max<size_t>(1, element_count / 16));
 }
 
 ColumnString::ColumnString(const std::vector<std::string>& data)
@@ -190,8 +196,7 @@ ColumnString::ColumnString(std::vector<std::string>&& data)
 ColumnString::~ColumnString()
 {}
 
-void ColumnString::Reserve(size_t new_cap)
-{
+void ColumnString::Reserve(size_t new_cap) {
     items_.reserve(new_cap);
     // 16 is arbitrary number, assumption that string values are about ~256 bytes long.
     blocks_.reserve(std::max<size_t>(1, new_cap / 16));
diff --git a/clickhouse/columns/string.h b/clickhouse/columns/string.h
index 6d6d5e77..d6006556 100644
--- a/clickhouse/columns/string.h
+++ b/clickhouse/columns/string.h
@@ -28,7 +28,7 @@ class ColumnFixedString : public Column {
     }
 
     /// Increase the capacity of the column for large block insertion.
-    void Reserve(size_t) override {};
+    void Reserve(size_t) override;
 
     /// Appends one element to the column.
     void Append(std::string_view str);
diff --git a/clickhouse/columns/tuple.cpp b/clickhouse/columns/tuple.cpp
index 24864063..56858590 100644
--- a/clickhouse/columns/tuple.cpp
+++ b/clickhouse/columns/tuple.cpp
@@ -20,9 +20,10 @@ size_t ColumnTuple::TupleSize() const {
     return columns_.size();
 }
 
-void ColumnTuple::Reserve(size_t new_cap)
-{
-    columns_.reserve(new_cap);
+void ColumnTuple::Reserve(size_t new_cap) {
+    for (auto& column : columns_) {
+        column->Reserve(new_cap);
+    }  
 }
 
 void ColumnTuple::Append(ColumnRef column) {
diff --git a/clickhouse/columns/uuid.cpp b/clickhouse/columns/uuid.cpp
index 72d3d2b8..fbaff97d 100644
--- a/clickhouse/columns/uuid.cpp
+++ b/clickhouse/columns/uuid.cpp
@@ -34,8 +34,7 @@ const UUID ColumnUUID::At(size_t n) const {
     return UUID(data_->At(n * 2), data_->At(n * 2 + 1));
 }
 
-void ColumnUUID::Reserve(size_t new_cap)
-{
+void ColumnUUID::Reserve(size_t new_cap) {
     data_->Reserve(new_cap);
 }
 

From d343428241380537f7212406f051c0d5057fbd1e Mon Sep 17 00:00:00 2001
From: wangwei <1261385937@qq.com>
Date: Wed, 1 Nov 2023 17:55:49 +0800
Subject: [PATCH 3/3] add ut

---
 ut/Column_ut.cpp | 50 +++++++++++++-----------------------------------
 ut/utils_meta.h  | 14 ++++++++++++++
 2 files changed, 27 insertions(+), 37 deletions(-)

diff --git a/ut/Column_ut.cpp b/ut/Column_ut.cpp
index 9eb3c7cf..bac666ec 100644
--- a/ut/Column_ut.cpp
+++ b/ut/Column_ut.cpp
@@ -376,25 +376,18 @@ TYPED_TEST(GenericColumnTest, Swap) {
 #endif
 
 TYPED_TEST(GenericColumnTest, ReserveAndCapacity) {
-    if constexpr (
-        // TODO(venemkov): test that ColumnType has Reserve() and Capacity() methods
-        is_one_of_v<typename TestFixture::ColumnType,
-            // Only types that support Reserve() and Capacity() methods
-            ColumnUInt8,
-            ColumnUInt16,
-            ColumnUInt32,
-            ColumnUInt64,
-            ColumnInt8,
-            ColumnInt16,
-            ColumnInt32,
-            ColumnInt64,
-            ColumnInt128,
-            ColumnFloat32,
-            ColumnFloat64,
-            ColumnDate,
-            ColumnDate32,
-            ColumnDateTime>) {
-
+    using column_type = typename TestFixture::ColumnType;
+    auto [column0, values] = this->MakeColumnWithValues(2);
+    auto values_copy = values;
+    EXPECT_NO_THROW(column0->Reserve(0u));
+    EXPECT_EQ(2u, column0->Size());
+    EXPECT_TRUE(CompareRecursive(values, values_copy));
+
+    auto column1 = this->MakeColumn();
+    column1->Reserve(10u);
+    EXPECT_EQ(0u, column1->Size());
+
+    if constexpr (has_method_Reserve_v<column_type> && has_method_Capacity_v<column_type>) {
         auto column = this->MakeColumn();
         EXPECT_EQ(0u, column->Capacity());
         EXPECT_NO_THROW(column->Reserve(100u));
@@ -408,24 +401,7 @@ TYPED_TEST(GenericColumnTest, ReserveAndCapacity) {
 
 
 TYPED_TEST(GenericColumnTest, GetWritableData) {
-    if constexpr (
-        // TODO(venemkov): test that ColumnType has GetWritableData() method
-        is_one_of_v<typename TestFixture::ColumnType,
-        // Only types that support GetWritableData() method
-                    ColumnUInt8,
-                    ColumnUInt16,
-                    ColumnUInt32,
-                    ColumnUInt64,
-                    ColumnInt8,
-                    ColumnInt16,
-                    ColumnInt32,
-                    ColumnInt64,
-                    ColumnInt128,
-                    ColumnFloat32,
-                    ColumnFloat64,
-                    ColumnDate,
-                    ColumnDate32,
-                    ColumnDateTime>) {
+    if constexpr (has_method_GetWritableData_v<typename TestFixture::ColumnType>) {
         auto [column, values] = this->MakeColumnWithValues(111);
         // Do conversion from time_t to internal representation, similar to what ColumnDate and ColumnDate32 do
         if constexpr (is_one_of_v<typename TestFixture::ColumnType,
diff --git a/ut/utils_meta.h b/ut/utils_meta.h
index 6cf55d2e..5b08c319 100644
--- a/ut/utils_meta.h
+++ b/ut/utils_meta.h
@@ -66,3 +66,17 @@ struct is_one_of<F, S, T...> {
 
 template <typename F, typename S, typename... T>
 inline constexpr bool is_one_of_v = is_one_of<F, S, T...>::value;
+
+
+#define HAS_METHOD(FUN)															            \
+template <typename T, class U = void>														\
+struct has_method_##FUN : std::false_type {};										        \
+template <typename T>																		\
+struct has_method_##FUN<T, std::enable_if_t<std::is_member_function_pointer_v<decltype(&T::FUN)>>> \
+: std::true_type {};																		\
+template <class T>																			\
+constexpr bool has_method_##FUN##_v = has_method_##FUN<T>::value;
+
+HAS_METHOD(Reserve);
+HAS_METHOD(Capacity);
+HAS_METHOD(GetWritableData);