| /** |
| * 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. |
| */ |
| |
| /** |
| * File format description for the parquet file format |
| */ |
| namespace cpp parquet |
| namespace java org.apache.parquet.format |
| |
| /** |
| * Types supported by Parquet. These types are intended to be used in combination |
| * with the encodings to control the on disk storage format. |
| * For example INT16 is not included as a type since a good encoding of INT32 |
| * would handle this. |
| */ |
| enum Type { |
| BOOLEAN = 0; |
| INT32 = 1; |
| INT64 = 2; |
| INT96 = 3; // deprecated, only used by legacy implementations. |
| FLOAT = 4; |
| DOUBLE = 5; |
| BYTE_ARRAY = 6; |
| FIXED_LEN_BYTE_ARRAY = 7; |
| } |
| |
| /** |
| * Common types used by frameworks(e.g. hive, pig) using parquet. This helps map |
| * between types in those frameworks to the base types in parquet. This is only |
| * metadata and not needed to read or write the data. |
| */ |
| enum ConvertedType { |
| /** a BYTE_ARRAY actually contains UTF8 encoded chars */ |
| UTF8 = 0; |
| |
| /** a map is converted as an optional field containing a repeated key/value pair */ |
| MAP = 1; |
| |
| /** a key/value pair is converted into a group of two fields */ |
| MAP_KEY_VALUE = 2; |
| |
| /** a list is converted into an optional field containing a repeated field for its |
| * values */ |
| LIST = 3; |
| |
| /** an enum is converted into a binary field */ |
| ENUM = 4; |
| |
| /** |
| * A decimal value. |
| * |
| * This may be used to annotate binary or fixed primitive types. The |
| * underlying byte array stores the unscaled value encoded as two's |
| * complement using big-endian byte order (the most significant byte is the |
| * zeroth element). The value of the decimal is the value * 10^{-scale}. |
| * |
| * This must be accompanied by a (maximum) precision and a scale in the |
| * SchemaElement. The precision specifies the number of digits in the decimal |
| * and the scale stores the location of the decimal point. For example 1.23 |
| * would have precision 3 (3 total digits) and scale 2 (the decimal point is |
| * 2 digits over). |
| */ |
| DECIMAL = 5; |
| |
| /** |
| * A Date |
| * |
| * Stored as days since Unix epoch, encoded as the INT32 physical type. |
| * |
| */ |
| DATE = 6; |
| |
| /** |
| * A time |
| * |
| * The total number of milliseconds since midnight. The value is stored |
| * as an INT32 physical type. |
| */ |
| TIME_MILLIS = 7; |
| |
| /** |
| * A time. |
| * |
| * The total number of microseconds since midnight. The value is stored as |
| * an INT64 physical type. |
| */ |
| TIME_MICROS = 8; |
| |
| /** |
| * A date/time combination |
| * |
| * Date and time recorded as milliseconds since the Unix epoch. Recorded as |
| * a physical type of INT64. |
| */ |
| TIMESTAMP_MILLIS = 9; |
| |
| /** |
| * A date/time combination |
| * |
| * Date and time recorded as microseconds since the Unix epoch. The value is |
| * stored as an INT64 physical type. |
| */ |
| TIMESTAMP_MICROS = 10; |
| |
| |
| /** |
| * An unsigned integer value. |
| * |
| * The number describes the maximum number of meainful data bits in |
| * the stored value. 8, 16 and 32 bit values are stored using the |
| * INT32 physical type. 64 bit values are stored using the INT64 |
| * physical type. |
| * |
| */ |
| UINT_8 = 11; |
| UINT_16 = 12; |
| UINT_32 = 13; |
| UINT_64 = 14; |
| |
| /** |
| * A signed integer value. |
| * |
| * The number describes the maximum number of meainful data bits in |
| * the stored value. 8, 16 and 32 bit values are stored using the |
| * INT32 physical type. 64 bit values are stored using the INT64 |
| * physical type. |
| * |
| */ |
| INT_8 = 15; |
| INT_16 = 16; |
| INT_32 = 17; |
| INT_64 = 18; |
| |
| /** |
| * An embedded JSON document |
| * |
| * A JSON document embedded within a single UTF8 column. |
| */ |
| JSON = 19; |
| |
| /** |
| * An embedded BSON document |
| * |
| * A BSON document embedded within a single BINARY column. |
| */ |
| BSON = 20; |
| |
| /** |
| * An interval of time |
| * |
| * This type annotates data stored as a FIXED_LEN_BYTE_ARRAY of length 12 |
| * This data is composed of three separate little endian unsigned |
| * integers. Each stores a component of a duration of time. The first |
| * integer identifies the number of months associated with the duration, |
| * the second identifies the number of days associated with the duration |
| * and the third identifies the number of milliseconds associated with |
| * the provided duration. This duration of time is independent of any |
| * particular timezone or date. |
| */ |
| INTERVAL = 21; |
| } |
| |
| /** |
| * Representation of Schemas |
| */ |
| enum FieldRepetitionType { |
| /** This field is required (can not be null) and each record has exactly 1 value. */ |
| REQUIRED = 0; |
| |
| /** The field is optional (can be null) and each record has 0 or 1 values. */ |
| OPTIONAL = 1; |
| |
| /** The field is repeated and can contain 0 or more values */ |
| REPEATED = 2; |
| } |
| |
| /** |
| * Statistics per row group and per page |
| * All fields are optional. |
| */ |
| struct Statistics { |
| /** |
| * DEPRECATED: min and max value of the column. Use min_value and max_value. |
| * |
| * Values are encoded using PLAIN encoding, except that variable-length byte |
| * arrays do not include a length prefix. |
| * |
| * These fields encode min and max values determined by signed comparison |
| * only. New files should use the correct order for a column's logical type |
| * and store the values in the min_value and max_value fields. |
| * |
| * To support older readers, these may be set when the column order is |
| * signed. |
| */ |
| 1: optional binary max; |
| 2: optional binary min; |
| /** count of null value in the column */ |
| 3: optional i64 null_count; |
| /** count of distinct values occurring */ |
| 4: optional i64 distinct_count; |
| /** |
| * Min and max values for the column, determined by its ColumnOrder. |
| * |
| * Values are encoded using PLAIN encoding, except that variable-length byte |
| * arrays do not include a length prefix. |
| */ |
| 5: optional binary max_value; |
| 6: optional binary min_value; |
| } |
| |
| /** Empty structs to use as logical type annotations */ |
| struct StringType {} // allowed for BINARY, must be encoded with UTF-8 |
| struct UUIDType {} // allowed for FIXED[16], must encoded raw UUID bytes |
| struct MapType {} // see LogicalTypes.md |
| struct ListType {} // see LogicalTypes.md |
| struct EnumType {} // allowed for BINARY, must be encoded with UTF-8 |
| struct DateType {} // allowed for INT32 |
| |
| /** |
| * Logical type to annotate a column that is always null. |
| * |
| * Sometimes when discovering the schema of existing data, values are always |
| * null and the physical type can't be determined. This annotation signals |
| * the case where the physical type was guessed from all null values. |
| */ |
| struct NullType {} // allowed for any physical type, only null values stored |
| |
| /** |
| * Decimal logical type annotation |
| * |
| * To maintain forward-compatibility in v1, implementations using this logical |
| * type must also set scale and precision on the annotated SchemaElement. |
| * |
| * Allowed for physical types: INT32, INT64, FIXED, and BINARY |
| */ |
| struct DecimalType { |
| 1: required i32 scale |
| 2: required i32 precision |
| } |
| |
| /** Time units for logical types */ |
| struct MilliSeconds {} |
| struct MicroSeconds {} |
| struct NanoSeconds {} |
| union TimeUnit { |
| 1: MilliSeconds MILLIS |
| 2: MicroSeconds MICROS |
| 3: NanoSeconds NANOS |
| } |
| |
| /** |
| * Timestamp logical type annotation |
| * |
| * Allowed for physical types: INT64 |
| */ |
| struct TimestampType { |
| 1: required bool isAdjustedToUTC |
| 2: required TimeUnit unit |
| } |
| |
| /** |
| * Time logical type annotation |
| * |
| * Allowed for physical types: INT32 (millis), INT64 (micros, nanos) |
| */ |
| struct TimeType { |
| 1: required bool isAdjustedToUTC |
| 2: required TimeUnit unit |
| } |
| |
| /** |
| * Integer logical type annotation |
| * |
| * bitWidth must be 8, 16, 32, or 64. |
| * |
| * Allowed for physical types: INT32, INT64 |
| */ |
| struct IntType { |
| 1: required byte bitWidth |
| 2: required bool isSigned |
| } |
| |
| /** |
| * Embedded JSON logical type annotation |
| * |
| * Allowed for physical types: BINARY |
| */ |
| struct JsonType { |
| } |
| |
| /** |
| * Embedded BSON logical type annotation |
| * |
| * Allowed for physical types: BINARY |
| */ |
| struct BsonType { |
| } |
| |
| /** |
| * LogicalType annotations to replace ConvertedType. |
| * |
| * To maintain compatibility, implementations using LogicalType for a |
| * SchemaElement must also set the corresponding ConvertedType from the |
| * following table. |
| */ |
| union LogicalType { |
| 1: StringType STRING // use ConvertedType UTF8 |
| 2: MapType MAP // use ConvertedType MAP |
| 3: ListType LIST // use ConvertedType LIST |
| 4: EnumType ENUM // use ConvertedType ENUM |
| 5: DecimalType DECIMAL // use ConvertedType DECIMAL |
| 6: DateType DATE // use ConvertedType DATE |
| |
| // use ConvertedType TIME_MICROS for TIME(isAdjustedToUTC = true, unit = MICROS) |
| // use ConvertedType TIME_MILLIS for TIME(isAdjustedToUTC = true, unit = MILLIS) |
| 7: TimeType TIME |
| |
| // use ConvertedType TIMESTAMP_MICROS for TIMESTAMP(isAdjustedToUTC = true, unit = MICROS) |
| // use ConvertedType TIMESTAMP_MILLIS for TIMESTAMP(isAdjustedToUTC = true, unit = MILLIS) |
| 8: TimestampType TIMESTAMP |
| |
| // 9: reserved for INTERVAL |
| 10: IntType INTEGER // use ConvertedType INT_* or UINT_* |
| 11: NullType UNKNOWN // no compatible ConvertedType |
| 12: JsonType JSON // use ConvertedType JSON |
| 13: BsonType BSON // use ConvertedType BSON |
| 14: UUIDType UUID |
| } |
| |
| /** |
| * Represents a element inside a schema definition. |
| * - if it is a group (inner node) then type is undefined and num_children is defined |
| * - if it is a primitive type (leaf) then type is defined and num_children is undefined |
| * the nodes are listed in depth first traversal order. |
| */ |
| struct SchemaElement { |
| /** Data type for this field. Not set if the current element is a non-leaf node */ |
| 1: optional Type type; |
| |
| /** If type is FIXED_LEN_BYTE_ARRAY, this is the byte length of the vales. |
| * Otherwise, if specified, this is the maximum bit length to store any of the values. |
| * (e.g. a low cardinality INT col could have this set to 3). Note that this is |
| * in the schema, and therefore fixed for the entire file. |
| */ |
| 2: optional i32 type_length; |
| |
| /** repetition of the field. The root of the schema does not have a repetition_type. |
| * All other nodes must have one */ |
| 3: optional FieldRepetitionType repetition_type; |
| |
| /** Name of the field in the schema */ |
| 4: required string name; |
| |
| /** Nested fields. Since thrift does not support nested fields, |
| * the nesting is flattened to a single list by a depth-first traversal. |
| * The children count is used to construct the nested relationship. |
| * This field is not set when the element is a primitive type |
| */ |
| 5: optional i32 num_children; |
| |
| /** When the schema is the result of a conversion from another model |
| * Used to record the original type to help with cross conversion. |
| */ |
| 6: optional ConvertedType converted_type; |
| |
| /** Used when this column contains decimal data. |
| * See the DECIMAL converted type for more details. |
| */ |
| 7: optional i32 scale |
| 8: optional i32 precision |
| |
| /** When the original schema supports field ids, this will save the |
| * original field id in the parquet schema |
| */ |
| 9: optional i32 field_id; |
| |
| /** |
| * The logical type of this SchemaElement |
| * |
| * LogicalType replaces ConvertedType, but ConvertedType is still required |
| * for some logical types to ensure forward-compatibility in format v1. |
| */ |
| 10: optional LogicalType logicalType |
| } |
| |
| /** |
| * Encodings supported by Parquet. Not all encodings are valid for all types. These |
| * enums are also used to specify the encoding of definition and repetition levels. |
| * See the accompanying doc for the details of the more complicated encodings. |
| */ |
| enum Encoding { |
| /** Default encoding. |
| * BOOLEAN - 1 bit per value. 0 is false; 1 is true. |
| * INT32 - 4 bytes per value. Stored as little-endian. |
| * INT64 - 8 bytes per value. Stored as little-endian. |
| * FLOAT - 4 bytes per value. IEEE. Stored as little-endian. |
| * DOUBLE - 8 bytes per value. IEEE. Stored as little-endian. |
| * BYTE_ARRAY - 4 byte length stored as little endian, followed by bytes. |
| * FIXED_LEN_BYTE_ARRAY - Just the bytes. |
| */ |
| PLAIN = 0; |
| |
| /** Group VarInt encoding for INT32/INT64. |
| * This encoding is deprecated. It was never used |
| */ |
| // GROUP_VAR_INT = 1; |
| |
| /** |
| * Deprecated: Dictionary encoding. The values in the dictionary are encoded in the |
| * plain type. |
| * in a data page use RLE_DICTIONARY instead. |
| * in a Dictionary page use PLAIN instead |
| */ |
| PLAIN_DICTIONARY = 2; |
| |
| /** Group packed run length encoding. Usable for definition/repetition levels |
| * encoding and Booleans (on one bit: 0 is false; 1 is true.) |
| */ |
| RLE = 3; |
| |
| /** Bit packed encoding. This can only be used if the data has a known max |
| * width. Usable for definition/repetition levels encoding. |
| */ |
| BIT_PACKED = 4; |
| |
| /** Delta encoding for integers. This can be used for int columns and works best |
| * on sorted data |
| */ |
| DELTA_BINARY_PACKED = 5; |
| |
| /** Encoding for byte arrays to separate the length values and the data. The lengths |
| * are encoded using DELTA_BINARY_PACKED |
| */ |
| DELTA_LENGTH_BYTE_ARRAY = 6; |
| |
| /** Incremental-encoded byte array. Prefix lengths are encoded using DELTA_BINARY_PACKED. |
| * Suffixes are stored as delta length byte arrays. |
| */ |
| DELTA_BYTE_ARRAY = 7; |
| |
| /** Dictionary encoding: the ids are encoded using the RLE encoding |
| */ |
| RLE_DICTIONARY = 8; |
| } |
| |
| /** |
| * Supported compression algorithms. |
| * |
| * Codecs added in 2.4 can be read by readers based on 2.4 and later. |
| * Codec support may vary between readers based on the format version and |
| * libraries available at runtime. Gzip, Snappy, and LZ4 codecs are |
| * widely available, while Zstd and Brotli require additional libraries. |
| */ |
| enum CompressionCodec { |
| UNCOMPRESSED = 0; |
| SNAPPY = 1; |
| GZIP = 2; |
| LZO = 3; |
| BROTLI = 4; // Added in 2.4 |
| LZ4 = 5; // Added in 2.4 |
| ZSTD = 6; // Added in 2.4 |
| } |
| |
| enum PageType { |
| DATA_PAGE = 0; |
| INDEX_PAGE = 1; |
| DICTIONARY_PAGE = 2; |
| DATA_PAGE_V2 = 3; |
| BLOOM_FILTER_PAGE = 4; |
| } |
| |
| /** |
| * Enum to annotate whether lists of min/max elements inside ColumnIndex |
| * are ordered and if so, in which direction. |
| */ |
| enum BoundaryOrder { |
| UNORDERED = 0; |
| ASCENDING = 1; |
| DESCENDING = 2; |
| } |
| |
| /** Data page header */ |
| struct DataPageHeader { |
| /** Number of values, including NULLs, in this data page. **/ |
| 1: required i32 num_values |
| |
| /** Encoding used for this data page **/ |
| 2: required Encoding encoding |
| |
| /** Encoding used for definition levels **/ |
| 3: required Encoding definition_level_encoding; |
| |
| /** Encoding used for repetition levels **/ |
| 4: required Encoding repetition_level_encoding; |
| |
| /** Optional statistics for the data in this page**/ |
| 5: optional Statistics statistics; |
| } |
| |
| struct IndexPageHeader { |
| // TODO |
| } |
| |
| struct DictionaryPageHeader { |
| /** Number of values in the dictionary **/ |
| 1: required i32 num_values; |
| |
| /** Encoding using this dictionary page **/ |
| 2: required Encoding encoding |
| |
| /** If true, the entries in the dictionary are sorted in ascending order **/ |
| 3: optional bool is_sorted; |
| } |
| |
| /** |
| * New page format allowing reading levels without decompressing the data |
| * Repetition and definition levels are uncompressed |
| * The remaining section containing the data is compressed if is_compressed is true |
| **/ |
| struct DataPageHeaderV2 { |
| /** Number of values, including NULLs, in this data page. **/ |
| 1: required i32 num_values |
| /** Number of NULL values, in this data page. |
| Number of non-null = num_values - num_nulls which is also the number of values in the data section **/ |
| 2: required i32 num_nulls |
| /** Number of rows in this data page. which means pages change on record boundaries (r = 0) **/ |
| 3: required i32 num_rows |
| /** Encoding used for data in this page **/ |
| 4: required Encoding encoding |
| |
| // repetition levels and definition levels are always using RLE (without size in it) |
| |
| /** length of the definition levels */ |
| 5: required i32 definition_levels_byte_length; |
| /** length of the repetition levels */ |
| 6: required i32 repetition_levels_byte_length; |
| |
| /** whether the values are compressed. |
| Which means the section of the page between |
| definition_levels_byte_length + repetition_levels_byte_length + 1 and compressed_page_size (included) |
| is compressed with the compression_codec. |
| If missing it is considered compressed */ |
| 7: optional bool is_compressed = 1; |
| |
| /** optional statistics for this column chunk */ |
| 8: optional Statistics statistics; |
| } |
| |
| /** Block-based algorithm type annotation. **/ |
| struct SplitBlockAlgorithm {} |
| /** The algorithm used in Bloom filter. **/ |
| union BloomFilterAlgorithm { |
| /** Block-based Bloom filter. **/ |
| 1: SplitBlockAlgorithm BLOCK; |
| } |
| |
| /** Hash strategy type annotation. xxHash is an extremely fast non-cryptographic hash |
| * algorithm. It uses 64 bits version of xxHash. |
| **/ |
| struct XxHash {} |
| |
| /** |
| * The hash function used in Bloom filter. This function takes the hash of a column value |
| * using plain encoding. |
| **/ |
| union BloomFilterHash { |
| /** xxHash Strategy. **/ |
| 1: XxHash XXHASH; |
| } |
| /** |
| * Bloom filter header is stored at beginning of Bloom filter data of each column |
| * and followed by its bitset. |
| **/ |
| struct BloomFilterPageHeader { |
| /** The size of bitset in bytes **/ |
| 1: required i32 numBytes; |
| /** The algorithm for setting bits. **/ |
| 2: required BloomFilterAlgorithm algorithm; |
| /** The hash function used for Bloom filter. **/ |
| 3: required BloomFilterHash hash; |
| } |
| |
| struct PageHeader { |
| /** the type of the page: indicates which of the *_header fields is set **/ |
| 1: required PageType type |
| |
| /** Uncompressed page size in bytes (not including this header) **/ |
| 2: required i32 uncompressed_page_size |
| |
| /** Compressed page size in bytes (not including this header) **/ |
| 3: required i32 compressed_page_size |
| |
| /** The 32bit CRC for the page, to be be calculated as follows: |
| * - Using the standard CRC32 algorithm |
| * - On the data only, i.e. this header should not be included. 'Data' |
| * hereby refers to the concatenation of the repetition levels, the |
| * definition levels and the column value, in this exact order. |
| * - On the encoded versions of the repetition levels, definition levels and |
| * column values |
| * - On the compressed versions of the repetition levels, definition levels |
| * and column values where possible; |
| * - For v1 data pages, the repetition levels, definition levels and column |
| * values are always compressed together. If a compression scheme is |
| * specified, the CRC shall be calculated on the compressed version of |
| * this concatenation. If no compression scheme is specified, the CRC |
| * shall be calculated on the uncompressed version of this concatenation. |
| * - For v2 data pages, the repetition levels and definition levels are |
| * handled separately from the data and are never compressed (only |
| * encoded). If a compression scheme is specified, the CRC shall be |
| * calculated on the concatenation of the uncompressed repetition levels, |
| * uncompressed definition levels and the compressed column values. |
| * If no compression scheme is specified, the CRC shall be calculated on |
| * the uncompressed concatenation. |
| * If enabled, this allows for disabling checksumming in HDFS if only a few |
| * pages need to be read. |
| **/ |
| 4: optional i32 crc |
| |
| // Headers for page specific data. One only will be set. |
| 5: optional DataPageHeader data_page_header; |
| 6: optional IndexPageHeader index_page_header; |
| 7: optional DictionaryPageHeader dictionary_page_header; |
| 8: optional DataPageHeaderV2 data_page_header_v2; |
| 9: optional BloomFilterPageHeader bloom_filter_page_header; |
| } |
| |
| /** |
| * Wrapper struct to store key values |
| */ |
| struct KeyValue { |
| 1: required string key |
| 2: optional string value |
| } |
| |
| /** |
| * Wrapper struct to specify sort order |
| */ |
| struct SortingColumn { |
| /** The column index (in this row group) **/ |
| 1: required i32 column_idx |
| |
| /** If true, indicates this column is sorted in descending order. **/ |
| 2: required bool descending |
| |
| /** If true, nulls will come before non-null values, otherwise, |
| * nulls go at the end. */ |
| 3: required bool nulls_first |
| } |
| |
| /** |
| * statistics of a given page type and encoding |
| */ |
| struct PageEncodingStats { |
| |
| /** the page type (data/dic/...) **/ |
| 1: required PageType page_type; |
| |
| /** encoding of the page **/ |
| 2: required Encoding encoding; |
| |
| /** number of pages of this type with this encoding **/ |
| 3: required i32 count; |
| |
| } |
| |
| /** |
| * Description for column metadata |
| */ |
| struct ColumnMetaData { |
| /** Type of this column **/ |
| 1: required Type type |
| |
| /** Set of all encodings used for this column. The purpose is to validate |
| * whether we can decode those pages. **/ |
| 2: required list<Encoding> encodings |
| |
| /** Path in schema **/ |
| 3: required list<string> path_in_schema |
| |
| /** Compression codec **/ |
| 4: required CompressionCodec codec |
| |
| /** Number of values in this column **/ |
| 5: required i64 num_values |
| |
| /** total byte size of all uncompressed pages in this column chunk (including the headers) **/ |
| 6: required i64 total_uncompressed_size |
| |
| /** total byte size of all compressed pages in this column chunk (including the headers) **/ |
| 7: required i64 total_compressed_size |
| |
| /** Optional key/value metadata **/ |
| 8: optional list<KeyValue> key_value_metadata |
| |
| /** Byte offset from beginning of file to first data page **/ |
| 9: required i64 data_page_offset |
| |
| /** Byte offset from beginning of file to root index page **/ |
| 10: optional i64 index_page_offset |
| |
| /** Byte offset from the beginning of file to first (only) dictionary page **/ |
| 11: optional i64 dictionary_page_offset |
| |
| /** optional statistics for this column chunk */ |
| 12: optional Statistics statistics; |
| |
| /** Set of all encodings used for pages in this column chunk. |
| * This information can be used to determine if all data pages are |
| * dictionary encoded for example **/ |
| 13: optional list<PageEncodingStats> encoding_stats; |
| |
| /** Byte offset from beginning of file to Bloom filter data. **/ |
| 14: optional i64 bloom_filter_offset; |
| } |
| |
| struct ColumnChunk { |
| /** File where column data is stored. If not set, assumed to be same file as |
| * metadata. This path is relative to the current file. |
| **/ |
| 1: optional string file_path |
| |
| /** Byte offset in file_path to the ColumnMetaData **/ |
| 2: required i64 file_offset |
| |
| /** Column metadata for this chunk. This is the same content as what is at |
| * file_path/file_offset. Having it here has it replicated in the file |
| * metadata. |
| **/ |
| 3: optional ColumnMetaData meta_data |
| |
| /** File offset of ColumnChunk's OffsetIndex **/ |
| 4: optional i64 offset_index_offset |
| |
| /** Size of ColumnChunk's OffsetIndex, in bytes **/ |
| 5: optional i32 offset_index_length |
| |
| /** File offset of ColumnChunk's ColumnIndex **/ |
| 6: optional i64 column_index_offset |
| |
| /** Size of ColumnChunk's ColumnIndex, in bytes **/ |
| 7: optional i32 column_index_length |
| } |
| |
| struct RowGroup { |
| /** Metadata for each column chunk in this row group. |
| * This list must have the same order as the SchemaElement list in FileMetaData. |
| **/ |
| 1: required list<ColumnChunk> columns |
| |
| /** Total byte size of all the uncompressed column data in this row group **/ |
| 2: required i64 total_byte_size |
| |
| /** Number of rows in this row group **/ |
| 3: required i64 num_rows |
| |
| /** If set, specifies a sort ordering of the rows in this RowGroup. |
| * The sorting columns can be a subset of all the columns. |
| */ |
| 4: optional list<SortingColumn> sorting_columns |
| } |
| |
| /** Empty struct to signal the order defined by the physical or logical type */ |
| struct TypeDefinedOrder {} |
| |
| /** |
| * Union to specify the order used for the min_value and max_value fields for a |
| * column. This union takes the role of an enhanced enum that allows rich |
| * elements (which will be needed for a collation-based ordering in the future). |
| * |
| * Possible values are: |
| * * TypeDefinedOrder - the column uses the order defined by its logical or |
| * physical type (if there is no logical type). |
| * |
| * If the reader does not support the value of this union, min and max stats |
| * for this column should be ignored. |
| */ |
| union ColumnOrder { |
| |
| /** |
| * The sort orders for logical types are: |
| * UTF8 - unsigned byte-wise comparison |
| * INT8 - signed comparison |
| * INT16 - signed comparison |
| * INT32 - signed comparison |
| * INT64 - signed comparison |
| * UINT8 - unsigned comparison |
| * UINT16 - unsigned comparison |
| * UINT32 - unsigned comparison |
| * UINT64 - unsigned comparison |
| * DECIMAL - signed comparison of the represented value |
| * DATE - signed comparison |
| * TIME_MILLIS - signed comparison |
| * TIME_MICROS - signed comparison |
| * TIMESTAMP_MILLIS - signed comparison |
| * TIMESTAMP_MICROS - signed comparison |
| * INTERVAL - unsigned comparison |
| * JSON - unsigned byte-wise comparison |
| * BSON - unsigned byte-wise comparison |
| * ENUM - unsigned byte-wise comparison |
| * LIST - undefined |
| * MAP - undefined |
| * |
| * In the absence of logical types, the sort order is determined by the physical type: |
| * BOOLEAN - false, true |
| * INT32 - signed comparison |
| * INT64 - signed comparison |
| * INT96 (only used for legacy timestamps) - undefined |
| * FLOAT - signed comparison of the represented value (*) |
| * DOUBLE - signed comparison of the represented value (*) |
| * BYTE_ARRAY - unsigned byte-wise comparison |
| * FIXED_LEN_BYTE_ARRAY - unsigned byte-wise comparison |
| * |
| * (*) Because the sorting order is not specified properly for floating |
| * point values (relations vs. total ordering) the following |
| * compatibility rules should be applied when reading statistics: |
| * - If the min is a NaN, it should be ignored. |
| * - If the max is a NaN, it should be ignored. |
| * - If the min is +0, the row group may contain -0 values as well. |
| * - If the max is -0, the row group may contain +0 values as well. |
| * - When looking for NaN values, min and max should be ignored. |
| */ |
| 1: TypeDefinedOrder TYPE_ORDER; |
| } |
| |
| struct PageLocation { |
| /** Offset of the page in the file **/ |
| 1: required i64 offset |
| |
| /** |
| * Size of the page, including header. Sum of compressed_page_size and header |
| * length |
| */ |
| 2: required i32 compressed_page_size |
| |
| /** |
| * Index within the RowGroup of the first row of the page; this means pages |
| * change on record boundaries (r = 0). |
| */ |
| 3: required i64 first_row_index |
| } |
| |
| struct OffsetIndex { |
| /** |
| * PageLocations, ordered by increasing PageLocation.offset. It is required |
| * that page_locations[i].first_row_index < page_locations[i+1].first_row_index. |
| */ |
| 1: required list<PageLocation> page_locations |
| } |
| |
| /** |
| * Description for ColumnIndex. |
| * Each <array-field>[i] refers to the page at OffsetIndex.page_locations[i] |
| */ |
| struct ColumnIndex { |
| /** |
| * A list of Boolean values to determine the validity of the corresponding |
| * min and max values. If true, a page contains only null values, and writers |
| * have to set the corresponding entries in min_values and max_values to |
| * byte[0], so that all lists have the same length. If false, the |
| * corresponding entries in min_values and max_values must be valid. |
| */ |
| 1: required list<bool> null_pages |
| |
| /** |
| * Two lists containing lower and upper bounds for the values of each page. |
| * These may be the actual minimum and maximum values found on a page, but |
| * can also be (more compact) values that do not exist on a page. For |
| * example, instead of storing ""Blart Versenwald III", a writer may set |
| * min_values[i]="B", max_values[i]="C". Such more compact values must still |
| * be valid values within the column's logical type. Readers must make sure |
| * that list entries are populated before using them by inspecting null_pages. |
| */ |
| 2: required list<binary> min_values |
| 3: required list<binary> max_values |
| |
| /** |
| * Stores whether both min_values and max_values are orderd and if so, in |
| * which direction. This allows readers to perform binary searches in both |
| * lists. Readers cannot assume that max_values[i] <= min_values[i+1], even |
| * if the lists are ordered. |
| */ |
| 4: required BoundaryOrder boundary_order |
| |
| /** A list containing the number of null values for each page **/ |
| 5: optional list<i64> null_counts |
| } |
| |
| /** |
| * Description for file metadata |
| */ |
| struct FileMetaData { |
| /** Version of this file **/ |
| 1: required i32 version |
| |
| /** Parquet schema for this file. This schema contains metadata for all the columns. |
| * The schema is represented as a tree with a single root. The nodes of the tree |
| * are flattened to a list by doing a depth-first traversal. |
| * The column metadata contains the path in the schema for that column which can be |
| * used to map columns to nodes in the schema. |
| * The first element is the root **/ |
| 2: required list<SchemaElement> schema; |
| |
| /** Number of rows in this file **/ |
| 3: required i64 num_rows |
| |
| /** Row groups in this file **/ |
| 4: required list<RowGroup> row_groups |
| |
| /** Optional key/value metadata **/ |
| 5: optional list<KeyValue> key_value_metadata |
| |
| /** String for application that wrote this file. This should be in the format |
| * <Application> version <App Version> (build <App Build Hash>). |
| * e.g. impala version 1.0 (build 6cf94d29b2b7115df4de2c06e2ab4326d721eb55) |
| **/ |
| 6: optional string created_by |
| |
| /** |
| * Sort order used for the min_value and max_value fields of each column in |
| * this file. Sort orders are listed in the order matching the columns in the |
| * schema. The indexes are not necessary the same though, because only leaf |
| * nodes of the schema are represented in the list of sort orders. |
| * |
| * Without column_orders, the meaning of the min_value and max_value fields is |
| * undefined. To ensure well-defined behaviour, if min_value and max_value are |
| * written to a Parquet file, column_orders must be written as well. |
| * |
| * The obsolete min and max fields are always sorted by signed comparison |
| * regardless of column_orders. |
| */ |
| 7: optional list<ColumnOrder> column_orders; |
| } |
| |