[ARROW-1785] Fix comment

cpp/src/arrow/ipc/json-internal.cc

@@ -43,22 +43,6 @@ namespace ipc {
 namespace json {
 namespace internal {
 
-static std::string GetBufferTypeName(BufferType type) {
-  switch (type) {
-    case BufferType::DATA:
-      return "DATA";
-    case BufferType::OFFSET:
-      return "OFFSET";
-    case BufferType::TYPE:
-      return "TYPE";
-    case BufferType::VALIDITY:
-      return "VALIDITY";
-    default:
-      break;
-  }
-  return "UNKNOWN";
-}
-
 static std::string GetFloatingPrecisionName(FloatingPoint::Precision precision) {
   switch (precision) {
     case FloatingPoint::HALF:
@@ -174,12 +158,9 @@ class SchemaWriter {
       RETURN_NOT_OK(WriteDictionaryMetadata(dict_type));
 
       const DataType& dictionary_type = *dict_type.dictionary()->type();
-      const DataType& index_type = *dict_type.index_type();
       RETURN_NOT_OK(WriteChildren(dictionary_type.children()));
-      WriteBufferLayout(index_type.GetBufferLayout());
     } else {
       RETURN_NOT_OK(WriteChildren(type.children()));
-      WriteBufferLayout(type.GetBufferLayout());
     }
 
     writer_->EndObject();
@@ -301,26 +282,6 @@ class SchemaWriter {
     return Status::OK();
   }
 
-  void WriteBufferLayout(const std::vector<BufferDescr>& buffer_layout) {
-    writer_->Key("typeLayout");
-    writer_->StartObject();
-    writer_->Key("vectors");
-    writer_->StartArray();
-
-    for (const BufferDescr& buffer : buffer_layout) {
-      writer_->StartObject();
-      writer_->Key("type");
-      writer_->String(GetBufferTypeName(buffer.type()));
-
-      writer_->Key("typeBitWidth");
-      writer_->Int(buffer.bit_width());
-
-      writer_->EndObject();
-    }
-    writer_->EndArray();
-    writer_->EndObject();
-  }
-
   Status WriteChildren(const std::vector<std::shared_ptr<Field>>& children) {
     writer_->Key("children");
     writer_->StartArray();

cpp/src/arrow/ipc/metadata-internal.cc

@@ -54,7 +54,6 @@ using DictionaryOffset = flatbuffers::Offset<flatbuf::DictionaryEncoding>;
 using FieldOffset = flatbuffers::Offset<flatbuf::Field>;
 using KeyValueOffset = flatbuffers::Offset<flatbuf::KeyValue>;
 using RecordBatchOffset = flatbuffers::Offset<flatbuf::RecordBatch>;
-using VectorLayoutOffset = flatbuffers::Offset<arrow::flatbuf::VectorLayout>;
 using Offset = flatbuffers::Offset<void>;
 using FBString = flatbuffers::Offset<flatbuffers::String>;
 
@@ -341,34 +340,8 @@ static Status TypeFromFlatbuffer(flatbuf::Type type, const void* type_data,
 // TODO(wesm): Convert this to visitor pattern
 static Status TypeToFlatbuffer(FBB& fbb, const DataType& type,
                                std::vector<FieldOffset>* children,
-                               std::vector<VectorLayoutOffset>* layout,
                                flatbuf::Type* out_type, DictionaryMemo* dictionary_memo,
                                Offset* offset) {
-  std::vector<BufferDescr> buffer_layout = type.GetBufferLayout();
-  for (const BufferDescr& descr : buffer_layout) {
-    flatbuf::VectorType vector_type;
-    switch (descr.type()) {
-      case BufferType::OFFSET:
-        vector_type = flatbuf::VectorType_OFFSET;
-        break;
-      case BufferType::DATA:
-        vector_type = flatbuf::VectorType_DATA;
-        break;
-      case BufferType::VALIDITY:
-        vector_type = flatbuf::VectorType_VALIDITY;
-        break;
-      case BufferType::TYPE:
-        vector_type = flatbuf::VectorType_TYPE;
-        break;
-      default:
-        vector_type = flatbuf::VectorType_DATA;
-        break;
-    }
-    auto offset = flatbuf::CreateVectorLayout(
-        fbb, static_cast<int16_t>(descr.bit_width()), vector_type);
-    layout->push_back(offset);
-  }
-
   const DataType* value_type = &type;
 
   if (type.id() == Type::DICTIONARY) {
@@ -543,14 +516,11 @@ static Status FieldToFlatbuffer(FBB& fbb, const Field& field,
 
   flatbuf::Type type_enum;
   Offset type_offset;
-  Offset type_layout;
   std::vector<FieldOffset> children;
-  std::vector<VectorLayoutOffset> layout;
 
-  RETURN_NOT_OK(TypeToFlatbuffer(fbb, *field.type(), &children, &layout, &type_enum,
+  RETURN_NOT_OK(TypeToFlatbuffer(fbb, *field.type(), &children, &type_enum,
                                  dictionary_memo, &type_offset));
   auto fb_children = fbb.CreateVector(children);
-  auto fb_layout = fbb.CreateVector(layout);
 
   DictionaryOffset dictionary = 0;
   if (field.type()->id() == Type::DICTIONARY) {
@@ -560,7 +530,7 @@ static Status FieldToFlatbuffer(FBB& fbb, const Field& field,
 
   // TODO: produce the list of VectorTypes
   *offset = flatbuf::CreateField(fbb, fb_name, field.nullable(), type_enum, type_offset,
-                                 dictionary, fb_children, fb_layout);
+                                 dictionary, fb_children);
 
   return Status::OK();
 }

cpp/src/arrow/type.cc

@@ -474,43 +474,6 @@ std::shared_ptr<DataType> decimal(int32_t precision, int32_t scale) {
   return std::make_shared<Decimal128Type>(precision, scale);
 }
 
-static const BufferDescr kValidityBuffer(BufferType::VALIDITY, 1);
-static const BufferDescr kOffsetBuffer(BufferType::OFFSET, 32);
-static const BufferDescr kTypeBuffer(BufferType::TYPE, 32);
-static const BufferDescr kBooleanBuffer(BufferType::DATA, 1);
-static const BufferDescr kValues64(BufferType::DATA, 64);
-static const BufferDescr kValues32(BufferType::DATA, 32);
-static const BufferDescr kValues16(BufferType::DATA, 16);
-static const BufferDescr kValues8(BufferType::DATA, 8);
-
-std::vector<BufferDescr> FixedWidthType::GetBufferLayout() const {
-  return {kValidityBuffer, BufferDescr(BufferType::DATA, bit_width())};
-}
-
-std::vector<BufferDescr> NullType::GetBufferLayout() const { return {}; }
-
-std::vector<BufferDescr> BinaryType::GetBufferLayout() const {
-  return {kValidityBuffer, kOffsetBuffer, kValues8};
-}
-
-std::vector<BufferDescr> FixedSizeBinaryType::GetBufferLayout() const {
-  return {kValidityBuffer, BufferDescr(BufferType::DATA, bit_width())};
-}
-
-std::vector<BufferDescr> ListType::GetBufferLayout() const {
-  return {kValidityBuffer, kOffsetBuffer};
-}
-
-std::vector<BufferDescr> StructType::GetBufferLayout() const { return {kValidityBuffer}; }
-
-std::vector<BufferDescr> UnionType::GetBufferLayout() const {
-  if (mode_ == UnionMode::SPARSE) {
-    return {kValidityBuffer, kTypeBuffer};
-  } else {
-    return {kValidityBuffer, kTypeBuffer, kOffsetBuffer};
-  }
-}
-
 std::string Decimal128Type::ToString() const {
   std::stringstream s;
   s << "decimal(" << precision_ << ", " << scale_ << ")";

cpp/src/arrow/type.h

@@ -133,20 +133,6 @@ struct Type {
   };
 };
 
-enum class BufferType : char { DATA, OFFSET, TYPE, VALIDITY };
-
-class BufferDescr {
- public:
-  BufferDescr(BufferType type, int bit_width) : type_(type), bit_width_(bit_width) {}
-
-  BufferType type() const { return type_; }
-  int bit_width() const { return bit_width_; }
-
- private:
-  BufferType type_;
-  int bit_width_;
-};
-
 class ARROW_EXPORT DataType {
  public:
   explicit DataType(Type::type id) : id_(id) {}
@@ -176,8 +162,6 @@ class ARROW_EXPORT DataType {
   /// \since 0.7.0
   virtual std::string name() const = 0;
 
-  virtual std::vector<BufferDescr> GetBufferLayout() const = 0;
-
   Type::type id() const { return id_; }
 
  protected:
@@ -201,8 +185,6 @@ class ARROW_EXPORT FixedWidthType : public DataType {
   using DataType::DataType;
 
   virtual int bit_width() const = 0;
-
-  std::vector<BufferDescr> GetBufferLayout() const override;
 };
 
 class ARROW_EXPORT PrimitiveCType : public FixedWidthType {
@@ -319,8 +301,6 @@ class ARROW_EXPORT NullType : public DataType, public NoExtraMeta {
   std::string ToString() const override;
 
   std::string name() const override { return "null"; }
-
-  std::vector<BufferDescr> GetBufferLayout() const override;
 };
 
 class ARROW_EXPORT BooleanType : public FixedWidthType, public NoExtraMeta {
@@ -425,8 +405,6 @@ class ARROW_EXPORT ListType : public NestedType {
   std::string ToString() const override;
 
   std::string name() const override { return "list"; }
-
-  std::vector<BufferDescr> GetBufferLayout() const override;
 };
 
 // BinaryType type is represents lists of 1-byte values.
@@ -440,8 +418,6 @@ class ARROW_EXPORT BinaryType : public DataType, public NoExtraMeta {
   std::string ToString() const override;
   std::string name() const override { return "binary"; }
 
-  std::vector<BufferDescr> GetBufferLayout() const override;
-
  protected:
   // Allow subclasses to change the logical type.
   explicit BinaryType(Type::type logical_type) : DataType(logical_type) {}
@@ -461,8 +437,6 @@ class ARROW_EXPORT FixedSizeBinaryType : public FixedWidthType, public Parametri
   std::string ToString() const override;
   std::string name() const override { return "fixed_size_binary"; }
 
-  std::vector<BufferDescr> GetBufferLayout() const override;
-
   int32_t byte_width() const { return byte_width_; }
   int bit_width() const override;
 
@@ -494,8 +468,6 @@ class ARROW_EXPORT StructType : public NestedType {
   Status Accept(TypeVisitor* visitor) const override;
   std::string ToString() const override;
   std::string name() const override { return "struct"; }
-
-  std::vector<BufferDescr> GetBufferLayout() const override;
 };
 
 class ARROW_EXPORT DecimalType : public FixedSizeBinaryType {
@@ -541,8 +513,6 @@ class ARROW_EXPORT UnionType : public NestedType {
   std::string name() const override { return "union"; }
   Status Accept(TypeVisitor* visitor) const override;
 
-  std::vector<BufferDescr> GetBufferLayout() const override;
-
   const std::vector<uint8_t>& type_codes() const { return type_codes_; }
 
   UnionMode::type mode() const { return mode_; }

format/Schema.fbs

@@ -211,32 +211,6 @@ union Type {
   Map
 }
 
-/// ----------------------------------------------------------------------
-/// The possible types of a vector
-
-enum VectorType: short {
-  /// used in List type, Dense Union and variable length primitive types (String, Binary)
-  OFFSET,
-  /// actual data, either wixed width primitive types in slots or variable width delimited by an OFFSET vector
-  DATA,
-  /// Bit vector indicating if each value is null
-  VALIDITY,
-  /// Type vector used in Union type
-  TYPE
-}
-
-/// ----------------------------------------------------------------------
-/// represents the physical layout of a buffer
-/// buffers have fixed width slots of a given type
-
-table VectorLayout {
-  /// the width of a slot in the buffer (typically 1, 8, 16, 32 or 64)
-  bit_width: short;
-  /// the purpose of the vector
-  type: VectorType;
-}
-
-
 /// ----------------------------------------------------------------------
 /// user defined key value pairs to add custom metadata to arrow
 /// key namespacing is the responsibility of the user
@@ -285,10 +259,7 @@ table Field {
 
   // children apply only to Nested data types like Struct, List and Union
   children: [Field];
-  /// layout of buffers produced for this type (as derived from the Type)
-  /// does not include children
-  /// each recordbatch will return instances of those Buffers.
-  layout: [ VectorLayout ];
+
   // User-defined metadata
   custom_metadata: [ KeyValue ];
 }

integration/data/simple.json

@@ -4,36 +4,20 @@
       {
         "name": "foo",
         "type": {"name": "int", "isSigned": true, "bitWidth": 32},
-        "nullable": true, "children": [],
-        "typeLayout": {
-          "vectors": [
-            {"type": "VALIDITY", "typeBitWidth": 1},
-            {"type": "DATA", "typeBitWidth": 32}
-          ]
-        }
+        "nullable": true,
+        "children": []
       },
       {
         "name": "bar",
         "type": {"name": "floatingpoint", "precision": "DOUBLE"},
-        "nullable": true, "children": [],
-        "typeLayout": {
-          "vectors": [
-            {"type": "VALIDITY", "typeBitWidth": 1},
-            {"type": "DATA", "typeBitWidth": 64}
-          ]
-        }
+        "nullable": true,
+        "children": []
       },
       {
         "name": "baz",
         "type": {"name": "utf8"},
-        "nullable": true, "children": [],
-        "typeLayout": {
-          "vectors": [
-            {"type": "VALIDITY", "typeBitWidth": 1},
-            {"type": "OFFSET", "typeBitWidth": 32},
-            {"type": "DATA", "typeBitWidth": 8}
-          ]
-        }
+        "nullable": true,
+        "children": []
       }
     ]
   },