apache-arrow/src/enum.ts

Apache Arrow columnar in-memory format

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export { MetadataVersion } from './fb/metadata-version.js';
export { UnionMode } from './fb/union-mode.js';
export { Precision } from './fb/precision.js';
export { DateUnit } from './fb/date-unit.js';
export { TimeUnit } from './fb/time-unit.js';
export { IntervalUnit } from './fb/interval-unit.js';
export { MessageHeader } from './fb/message-header.js';

/**
 * Main data type enumeration.
 *
 * Data types in this library are all *logical*. They can be expressed as
 * either a primitive physical type (bytes or bits of some fixed size), a
 * nested type consisting of other data types, or another data type (e.g. a
 * timestamp encoded as an int64).
 *
 * **Note**: Only non-negative enum values are written to an Arrow IPC payload.
 *
 * The rest of the values are specified here so TypeScript can narrow the type
 * signatures further beyond the base Arrow Types. The Arrow DataTypes include
 * metadata like `bitWidth` that impact the type signatures of the values we
 * accept and return.
 *
 * For example, the `Int8Vector` reads 1-byte numbers from an `Int8Array`, an
 * `Int32Vector` reads a 4-byte number from an `Int32Array`, and an `Int64Vector`
 * reads a pair of 4-byte lo, hi 32-bit integers as a zero-copy slice from the
 * underlying `Int32Array`.
 *
 * Library consumers benefit by knowing the narrowest type, since we can ensure
 * the types across all public methods are propagated, and never bail to `any`.
 * These values are _never_ used at runtime, and they will _never_ be written
 * to the flatbuffers metadata of serialized Arrow IPC payloads.
 */
export enum Type {
    NONE = 0, /** The default placeholder type */
    Null = 1, /** A NULL type having no physical storage */
    Int = 2, /** Signed or unsigned 8, 16, 32, or 64-bit little-endian integer */
    Float = 3, /** 2, 4, or 8-byte floating point value */
    Binary = 4, /** Variable-length bytes (no guarantee of UTF8-ness) */
    Utf8 = 5, /** UTF8 variable-length string as List<Char> */
    Bool = 6, /** Boolean as 1 bit, LSB bit-packed ordering */
    Decimal = 7, /** Precision-and-scale-based decimal type. Storage type depends on the parameters. */
    Date = 8, /** int32_t days or int64_t milliseconds since the UNIX epoch */
    Time = 9, /** Time as signed 32 or 64-bit integer, representing either seconds, milliseconds, microseconds, or nanoseconds since midnight since midnight */
    Timestamp = 10, /** Exact timestamp encoded with int64 since UNIX epoch (Default unit millisecond) */
    Interval = 11, /** YEAR_MONTH or DAY_TIME interval in SQL style */
    List = 12, /** A list of some logical data type */
    Struct = 13, /** Struct of logical types */
    Union = 14, /** Union of logical types */
    FixedSizeBinary = 15, /** Fixed-size binary. Each value occupies the same number of bytes */
    FixedSizeList = 16, /** Fixed-size list. Each value occupies the same number of bytes */
    Map = 17, /** Map of named logical types */
    Duration = 18, /** Measure of elapsed time in either seconds, milliseconds, microseconds or nanoseconds */
    LargeBinary = 19, /** Large variable-length bytes (no guarantee of UTF8-ness) */
    LargeUtf8 = 20, /** Large variable-length string as List<Char> */

    Dictionary = -1, /** Dictionary aka Category type */
    Int8 = -2,
    Int16 = -3,
    Int32 = -4,
    Int64 = -5,
    Uint8 = -6,
    Uint16 = -7,
    Uint32 = -8,
    Uint64 = -9,
    Float16 = -10,
    Float32 = -11,
    Float64 = -12,
    DateDay = -13,
    DateMillisecond = -14,
    TimestampSecond = -15,
    TimestampMillisecond = -16,
    TimestampMicrosecond = -17,
    TimestampNanosecond = -18,
    TimeSecond = -19,
    TimeMillisecond = -20,
    TimeMicrosecond = -21,
    TimeNanosecond = -22,
    DenseUnion = -23,
    SparseUnion = -24,
    IntervalDayTime = -25,
    IntervalYearMonth = -26,
    DurationSecond = -27,
    DurationMillisecond = -28,
    DurationMicrosecond = -29,
    DurationNanosecond = -30,
}

export enum BufferType {
    /**
     * used in List type, Dense Union and variable length primitive types (String, Binary)
     */
    OFFSET = 0,

    /**
     * actual data, either fixed width primitive types in slots or variable width delimited by an OFFSET vector
     */
    DATA = 1,

    /**
     * Bit vector indicating if each value is null
     */
    VALIDITY = 2,

    /**
     * Type vector used in Union type
     */
    TYPE = 3
}