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    Class NpgsqlBinaryExporter

    Provides an API for a binary COPY TO operation, a high-performance data export mechanism from a PostgreSQL table. Initiated by BeginBinaryExport(String)

    Inheritance
    Object
    NpgsqlBinaryExporter
    Implements
    IDisposable
    IAsyncDisposable
    Inherited Members
    Object.Equals(Object)
    Object.Equals(Object, Object)
    Object.GetHashCode()
    Object.GetType()
    Object.MemberwiseClone()
    Object.ReferenceEquals(Object, Object)
    Object.ToString()
    Namespace: Npgsql
    Assembly: Npgsql.dll
    Syntax
    public sealed class NpgsqlBinaryExporter : IDisposable, IAsyncDisposable

    Properties

    IsNull

    Returns whether the current column is null.

    Declaration
    public bool IsNull { get; }
    Property Value
    Type Description
    Boolean

    Timeout

    Current timeout

    Declaration
    public TimeSpan Timeout { set; }
    Property Value
    Type Description
    TimeSpan

    Methods

    Cancel()

    Cancels an ongoing export.

    Declaration
    public void Cancel()

    CancelAsync()

    Async cancels an ongoing export.

    Declaration
    public Task CancelAsync()
    Returns
    Type Description
    Task

    Dispose()

    Completes that binary export and sets the connection back to idle state

    Declaration
    public void Dispose()

    DisposeAsync()

    Async completes that binary export and sets the connection back to idle state

    Declaration
    public ValueTask DisposeAsync()
    Returns
    Type Description
    ValueTask

    Read<T>()

    Reads the current column, returns its value and moves ahead to the next column. If the column is null an exception is thrown.

    Declaration
    public T Read<T>()
    Returns
    Type Description
    T

    The value of the column

    Type Parameters
    Name Description
    T

    The type of the column to be read. This must correspond to the actual type or data corruption will occur. If in doubt, use Read<T>(NpgsqlDbType) to manually specify the type.

    Read<T>(NpgsqlDbType)

    Reads the current column, returns its value according to type and moves ahead to the next column. If the column is null an exception is thrown.

    Declaration
    public T Read<T>(NpgsqlDbType type)
    Parameters
    Type Name Description
    NpgsqlDbType type

    In some cases T isn't enough to infer the data type coming in from the database. This parameter can be used to unambiguously specify the type. An example is the JSONB type, for which T will be a simple string but for which type must be specified as Jsonb.

    Returns
    Type Description
    T

    The value of the column

    Type Parameters
    Name Description
    T

    The .NET type of the column to be read.

    ReadAsync<T>(NpgsqlDbType, CancellationToken)

    Reads the current column, returns its value according to type and moves ahead to the next column. If the column is null an exception is thrown.

    Declaration
    public ValueTask<T> ReadAsync<T>(NpgsqlDbType type, CancellationToken cancellationToken = default(CancellationToken))
    Parameters
    Type Name Description
    NpgsqlDbType type

    In some cases T isn't enough to infer the data type coming in from the database. This parameter can be used to unambiguously specify the type. An example is the JSONB type, for which T will be a simple string but for which type must be specified as Jsonb.

    CancellationToken cancellationToken

    An optional token to cancel the asynchronous operation. The default value is None.

    Returns
    Type Description
    ValueTask<T>

    The value of the column

    Type Parameters
    Name Description
    T

    The .NET type of the column to be read.

    ReadAsync<T>(CancellationToken)

    Reads the current column, returns its value and moves ahead to the next column. If the column is null an exception is thrown.

    Declaration
    public ValueTask<T> ReadAsync<T>(CancellationToken cancellationToken = default(CancellationToken))
    Parameters
    Type Name Description
    CancellationToken cancellationToken
    Returns
    Type Description
    ValueTask<T>

    The value of the column

    Type Parameters
    Name Description
    T

    The type of the column to be read. This must correspond to the actual type or data corruption will occur. If in doubt, use Read<T>(NpgsqlDbType) to manually specify the type.

    Skip()

    Skips the current column without interpreting its value.

    Declaration
    public void Skip()

    SkipAsync(CancellationToken)

    Skips the current column without interpreting its value.

    Declaration
    public Task SkipAsync(CancellationToken cancellationToken = default(CancellationToken))
    Parameters
    Type Name Description
    CancellationToken cancellationToken
    Returns
    Type Description
    Task

    StartRow()

    Starts reading a single row, must be invoked before reading any columns.

    Declaration
    public int StartRow()
    Returns
    Type Description
    Int32

    The number of columns in the row. -1 if there are no further rows. Note: This will currently be the same value for all rows, but this may change in the future.

    StartRowAsync(CancellationToken)

    Starts reading a single row, must be invoked before reading any columns.

    Declaration
    public ValueTask<int> StartRowAsync(CancellationToken cancellationToken = default(CancellationToken))
    Parameters
    Type Name Description
    CancellationToken cancellationToken
    Returns
    Type Description
    ValueTask<Int32>

    The number of columns in the row. -1 if there are no further rows. Note: This will currently be the same value for all rows, but this may change in the future.

    Implements

    System.IDisposable
    System.IAsyncDisposable
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