We use IEnumerables to return huge datasets from database:
public IEnumerable<Data> Read(...)
{
using(var connection = new SqlConnection(...))
{
// ...
while(reader.Read())
{
// ...
yield return item;
}
}
}
Now we want to use async methods to do the same. However there is no IEnumerables for async, so we have to collect data into a list until the entire dataset is loaded:
public async Task<List<Data>> ReadAsync(...)
{
var result = new List<Data>();
using(var connection = new SqlConnection(...))
{
// ...
while(await reader.ReadAsync().ConfigureAwait(false))
{
// ...
result.Add(item);
}
}
return result;
}
This will consume a huge amount of resources on server, because all data must be in the list before return. What is the best and easy to use async alternative for IEnumerables to work with large data streams? I would like to avoid storing all the data in memory while processing.
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