/// <summary>
///
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="importer"></param>
/// <param name="moveNextAsync"></param>
/// <param name="getCurrentAsync"></param>
/// <param name="writeAsync"></param>
/// <param name="identityBehavior"></param>
/// <param name="cancellationToken"></param>
/// <returns></returns>
private static async Task <int> BinaryImportWriteAsync <TEntity>(NpgsqlBinaryImporter importer,
Func <Task <bool> > moveNextAsync,
Func <Task <TEntity> > getCurrentAsync,
Func <TEntity, Task> writeAsync,
BulkImportIdentityBehavior identityBehavior,
CancellationToken cancellationToken = default)
where TEntity : class
{
var result = 0;
while (await moveNextAsync())
{
await importer.StartRowAsync(cancellationToken);
await EnsureCustomizedOrderColumnAsync(importer, identityBehavior, result,
cancellationToken);
await writeAsync(await getCurrentAsync());
result++;
}
await importer.CompleteAsync(cancellationToken);
return(result);
}
private async Task WriteToStreamAsync(NpgsqlBinaryImporter writer, TEntity entity, CancellationToken cancellationToken)
{
await writer.StartRowAsync(cancellationToken);
foreach (var columnDefinition in _columns)
{
await columnDefinition.WriteAsync(writer, entity, cancellationToken);
}
}
private async Task WriteToStream(NpgsqlBinaryImporter writer, IEnumerable <TEntity> entities)
{
foreach (var entity in entities)
{
await writer.StartRowAsync();
foreach (var columnDefinition in _columns)
{
await columnDefinition.Write(writer, entity);
}
}
}
public static async Task PerformBulkCopyAsync(this DbDataReader dr, NpgsqlBinaryImporter writer, DataColumnCollection columns = null)
{
columns ??= dr.GetSchemaTable().Columns;
while (await dr.ReadAsync())
{
await writer.StartRowAsync();
foreach (DataColumn col in columns)
{
switch (dr[col.Ordinal])
{
case bool x:
await writer.WriteAsync(x);
break;
case byte x:
await writer.WriteAsync(x);
break;
case sbyte x:
await writer.WriteAsync(x);
break;
case short x:
await writer.WriteAsync(x);
break;
case ushort x:
await writer.WriteAsync(x);
break;
case int x:
await writer.WriteAsync(x);
break;
case uint x:
await writer.WriteAsync(x);
break;
case long x:
await writer.WriteAsync(x);
break;
case ulong x:
await writer.WriteAsync(x);
break;
case Guid x:
await writer.WriteAsync(x);
break;
case DateTime x:
await writer.WriteAsync(x);
break;
case TimeSpan x:
await writer.WriteAsync(x);
break;
case string x:
await writer.WriteAsync(x);
break;
case null:
writer.WriteNull();
break;
}
}
}
await writer.CompleteAsync();
}
