Minor (backward compatitable) API improvement

clickhouse/columns/array.cpp

@@ -30,7 +30,7 @@ ColumnRef ColumnArray::GetAsColumn(size_t n) const {
     return data_->Slice(GetOffset(n), GetSize(n));
 }
 
-ColumnRef ColumnArray::Slice(size_t begin, size_t size) {
+ColumnRef ColumnArray::Slice(size_t begin, size_t size) const {
     auto result = std::make_shared<ColumnArray>(GetAsColumn(begin));
     result->OffsetsIncrease(1);
 

clickhouse/columns/array.h

@@ -36,7 +36,7 @@ class ColumnArray : public Column {
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t, size_t) override;
+    ColumnRef Slice(size_t, size_t) const override;
 
     void Swap(Column&) override;
 

clickhouse/columns/column.h

@@ -52,7 +52,7 @@ class Column : public std::enable_shared_from_this<Column> {
     virtual size_t Size() const = 0;
 
     /// Makes slice of the current column.
-    virtual ColumnRef Slice(size_t begin, size_t len) = 0;
+    virtual ColumnRef Slice(size_t begin, size_t len) const = 0;
 
     virtual void Swap(Column&) = 0;
 

clickhouse/columns/date.cpp

@@ -39,7 +39,7 @@ size_t ColumnDate::Size() const {
     return data_->Size();
 }
 
-ColumnRef ColumnDate::Slice(size_t begin, size_t len) {
+ColumnRef ColumnDate::Slice(size_t begin, size_t len) const {
     auto col = data_->Slice(begin, len)->As<ColumnUInt16>();
     auto result = std::make_shared<ColumnDate>();
 
@@ -105,7 +105,7 @@ void ColumnDateTime::Clear() {
     data_->Clear();
 }
 
-ColumnRef ColumnDateTime::Slice(size_t begin, size_t len) {
+ColumnRef ColumnDateTime::Slice(size_t begin, size_t len) const {
     auto col = data_->Slice(begin, len)->As<ColumnUInt32>();
     auto result = std::make_shared<ColumnDateTime>();
 
@@ -191,7 +191,7 @@ void ColumnDateTime64::Swap(Column& other) {
     data_.swap(col.data_);
 }
 
-ColumnRef ColumnDateTime64::Slice(size_t begin, size_t len) {
+ColumnRef ColumnDateTime64::Slice(size_t begin, size_t len) const {
     auto sliced_data = data_->Slice(begin, len)->As<ColumnDecimal>();
 
     return ColumnRef{new ColumnDateTime64(type_, sliced_data)};

clickhouse/columns/date.h

@@ -36,7 +36,7 @@ class ColumnDate : public Column {
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
 
     void Swap(Column& other) override;
 
@@ -78,7 +78,7 @@ class ColumnDateTime : public Column {
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
 
     void Swap(Column& other) override;
 
@@ -124,7 +124,7 @@ class ColumnDateTime64 : public Column {
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
 
     void Swap(Column& other) override;
 

clickhouse/columns/decimal.cpp

@@ -213,7 +213,7 @@ size_t ColumnDecimal::Size() const {
     return data_->Size();
 }
 
-ColumnRef ColumnDecimal::Slice(size_t begin, size_t len) {
+ColumnRef ColumnDecimal::Slice(size_t begin, size_t len) const {
     // coundn't use std::make_shared since this c-tor is private
     return ColumnRef{new ColumnDecimal(type_, data_->Slice(begin, len))};
 }

clickhouse/columns/decimal.h

@@ -23,7 +23,7 @@ class ColumnDecimal : public Column {
     void Save(CodedOutputStream* output) override;
     void Clear() override;
     size_t Size() const override;
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
     void Swap(Column& other) override;
     ItemView GetItem(size_t index) const override;
 

clickhouse/columns/enum.cpp

@@ -86,7 +86,7 @@ size_t ColumnEnum<T>::Size() const {
 }
 
 template <typename T>
-ColumnRef ColumnEnum<T>::Slice(size_t begin, size_t len) {
+ColumnRef ColumnEnum<T>::Slice(size_t begin, size_t len) const {
     return std::make_shared<ColumnEnum<T>>(type_, SliceVector(data_, begin, len));
 }
 

clickhouse/columns/enum.h

@@ -43,7 +43,7 @@ class ColumnEnum : public Column {
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
 
     void Swap(Column& other) override;
 

clickhouse/columns/ip4.cpp

@@ -74,7 +74,7 @@ size_t ColumnIPv4::Size() const {
     return data_->Size();
 }
 
-ColumnRef ColumnIPv4::Slice(size_t begin, size_t len) {
+ColumnRef ColumnIPv4::Slice(size_t begin, size_t len) const {
     return std::make_shared<ColumnIPv4>(data_->Slice(begin, len));
 }
 

clickhouse/columns/ip4.h

@@ -41,7 +41,7 @@ class ColumnIPv4 : public Column {
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
 
     void Swap(Column& other) override;
 

clickhouse/columns/ip6.cpp

@@ -74,7 +74,7 @@ size_t ColumnIPv6::Size() const {
     return data_->Size();
 }
 
-ColumnRef ColumnIPv6::Slice(size_t begin, size_t len) {
+ColumnRef ColumnIPv6::Slice(size_t begin, size_t len) const {
     return std::make_shared<ColumnIPv6>(data_->Slice(begin, len));
 }
 

clickhouse/columns/ip6.h

@@ -40,7 +40,7 @@ class ColumnIPv6 : public Column{
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
     void Swap(Column& other) override;
     ItemView GetItem(size_t index) const override;
 

clickhouse/columns/lowcardinality.cpp

@@ -297,7 +297,7 @@ size_t ColumnLowCardinality::Size() const {
     return index_column_->Size();
 }
 
-ColumnRef ColumnLowCardinality::Slice(size_t begin, size_t len) {
+ColumnRef ColumnLowCardinality::Slice(size_t begin, size_t len) const {
     begin = std::min(begin, Size());
     len = std::min(len, Size() - begin);
 

clickhouse/columns/lowcardinality.h

@@ -67,7 +67,7 @@ class ColumnLowCardinality : public Column {
     size_t Size() const override;
 
     /// Makes slice of current column, with compacted dictionary
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
 
     void Swap(Column& other) override;
     ItemView GetItem(size_t index) const override;

clickhouse/columns/nothing.h

@@ -35,7 +35,7 @@ class ColumnNothing : public Column {
 	std::nullptr_t operator [] (size_t) const { return nullptr; };
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t, size_t len) override {
+    ColumnRef Slice(size_t, size_t len) const override {
 		return std::make_shared<ColumnNothing>(len);
 	}
 

clickhouse/columns/nullable.cpp

@@ -70,7 +70,7 @@ size_t ColumnNullable::Size() const {
     return nulls_->Size();
 }
 
-ColumnRef ColumnNullable::Slice(size_t begin, size_t len) {
+ColumnRef ColumnNullable::Slice(size_t begin, size_t len) const {
     return std::make_shared<ColumnNullable>(nested_->Slice(begin, len), nulls_->Slice(begin, len));
 }
 

clickhouse/columns/nullable.h

@@ -41,7 +41,7 @@ class ColumnNullable : public Column {
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
     void Swap(Column&) override;
 
     ItemView GetItem(size_t) const override;

clickhouse/columns/numeric.cpp

@@ -76,7 +76,7 @@ size_t ColumnVector<T>::Size() const {
 }
 
 template <typename T>
-ColumnRef ColumnVector<T>::Slice(size_t begin, size_t len) {
+ColumnRef ColumnVector<T>::Slice(size_t begin, size_t len) const {
     return std::make_shared<ColumnVector<T>>(SliceVector(data_, begin, len));
 }
 

clickhouse/columns/numeric.h

@@ -46,7 +46,7 @@ class ColumnVector : public Column {
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
     void Swap(Column& other) override;
 
     ItemView GetItem(size_t index) const override;

clickhouse/columns/string.cpp

@@ -94,7 +94,7 @@ size_t ColumnFixedString::Size() const {
     return data_.size() / string_size_;
 }
 
-ColumnRef ColumnFixedString::Slice(size_t begin, size_t len) {
+ColumnRef ColumnFixedString::Slice(size_t begin, size_t len) const {
     auto result = std::make_shared<ColumnFixedString>(string_size_);
 
     if (begin < Size()) {
@@ -255,7 +255,7 @@ size_t ColumnString::Size() const {
     return items_.size();
 }
 
-ColumnRef ColumnString::Slice(size_t begin, size_t len) {
+ColumnRef ColumnString::Slice(size_t begin, size_t len) const {
     auto result = std::make_shared<ColumnString>();
 
     if (begin < items_.size()) {

clickhouse/columns/string.h

@@ -55,7 +55,7 @@ class ColumnFixedString : public Column {
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
 
     void Swap(Column& other) override;
 
@@ -107,7 +107,7 @@ class ColumnString : public Column {
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
     void Swap(Column& other) override;
     ItemView GetItem(size_t) const override;
 

clickhouse/columns/tuple.h

@@ -37,7 +37,7 @@ class ColumnTuple : public Column {
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t, size_t) override { return ColumnRef(); }
+    ColumnRef Slice(size_t, size_t) const override { return ColumnRef(); }
     void Swap(Column& other) override;
 
 private:

clickhouse/columns/uuid.cpp

@@ -55,7 +55,7 @@ size_t ColumnUUID::Size() const {
     return data_->Size() / 2;
 }
 
-ColumnRef ColumnUUID::Slice(size_t begin, size_t len) {
+ColumnRef ColumnUUID::Slice(size_t begin, size_t len) const {
     return std::make_shared<ColumnUUID>(data_->Slice(begin * 2, len * 2));
 }
 

clickhouse/columns/uuid.h

@@ -42,7 +42,7 @@ class ColumnUUID : public Column {
     size_t Size() const override;
 
     /// Makes slice of the current column.
-    ColumnRef Slice(size_t begin, size_t len) override;
+    ColumnRef Slice(size_t begin, size_t len) const override;
     void Swap(Column& other) override;
 
     ItemView GetItem(size_t) const override;