Query on freshly inserted Table Entities on Azure storage do not return all entities

Question

After inserting a 1000 table entities, the first read gives Less entities. I have a very simple program

        public static async Task RunTest(TableClient client)
        {
            List<TableEntity> tableEntities = new List<TableEntity>();

            // Create 1000 table entities 
            for (int i = 0; i < 1000; i++)
            {
                TableEntity entity = new TableEntity();
                entity.PartitionKey = $"{new Random().Next(1, 10)}";
                entity.RowKey = $"{Guid.NewGuid()}";
                tableEntities.Add(entity);
            }

            Parallel.ForEach(tableEntities, async entity =>
            {
                await client.UpsertEntityAsync(entity);
            });

            for (int i = 0; i < 10; i++)
            {
                List<TableEntity> results = new();
                var asyncdata = client.QueryAsync<TableEntity>(maxPerPage: 200).ConfigureAwait(false);
                await foreach (TableEntity page in asyncdata)
                {
                    results.Add(page);
                }
                Console.WriteLine($"Read entities :{results.Count}");    
            }
        }

I would expect 1000 table entities when reading them. But i get less entities than i inserted. Below is some output from the program.

Read entities :999
Read entities :1000
Read entities :1000
Read entities :1000
Read entities :1000
Read entities :1000
Read entities :1000
Read entities :1000
Read entities :1000
Read entities :1000

The behaviour is pretty consistent, when i run it for a second time:

Read entities :1999
Read entities :2000
Read entities :2000
Read entities :2000
Read entities :2000
Read entities :2000
Read entities :2000
Read entities :2000
Read entities :2000
Read entities :2000

This time there are 1000 new entities added but again not all are read. Sometimes i miss 1 record, or 4, the number differs from time to time.

Answer 1

Hi Patrick,

You are seeing incorrect results because you are querying the table before your code has finished inserting all of the entities. Please test using modified code below:

public static async Task RunTest(TableClient client)
{
    List<TableEntity> tableEntities = new List<TableEntity>();

    // Create 1000 table entities 
    for (int i = 0; i < 1000; i++)
    {
        TableEntity entity = new TableEntity();
        entity.PartitionKey = $"{new Random().Next(1, 10)}";
        entity.RowKey = $"{Guid.NewGuid()}";
        tableEntities.Add(entity);
    }

    await Parallel.ForEachAsync(tableEntities, async (entity, token) =>
        {
            await client.UpsertEntityAsync(entity);
        });

    for (int i = 0; i < 10; i++)
    {
        List<TableEntity> results = new();
        var asyncdata = client.QueryAsync<TableEntity>(maxPerPage: 200).ConfigureAwait(false);
        await foreach (TableEntity page in asyncdata)
        {
            results.Add(page);
        }
        Console.WriteLine($"Read entities :{results.Count}");
    }
}

Please click Accept Answer and upvote if the above was helpful.

Thanks.

-TP