Filtering with RowKey in Azure Table Storage using Azure.Data.Tables 12.8.3

Question

I recently updated to Azure.Data.Tables 12.8.3 and I used to filter data from tables in Azure Table Storage using row keys. I realize this is unlikely using the new implementation. I have shared my current approach using Expression Filters in the code snippet. Is there a better approach to achieve this or any alterations to make?

public virtual async Task<Page<T>> GetPagedFilteredResultsAsync(

Expression<Func<T, bool>> expressionFilter, string continuationToken, int pageSize = 0)

{

var query = _tableClient

.QueryAsync<T>(expressionFilter)

.AsPages(continuationToken, pageSize > 0 ? pageSize : defaultPageSize);

await foreach(var page in query)

{

return page;

}

return null;

}

The filter looks like this
Expression<Func<SomeEntity, bool>> expression =

e => e.PartitionKey == dto.SomeId

&& e.RowKey != null;

Answer 1

Hello Saumye Navarathna,

Thank you for posting your query here!

Your current approach using Expression<Func<T, bool>> to filter data from tables in Azure Table Storage is valid. However, if you want to filter by RowKey specifically, you can modify your expression filter as follows:

Expression<Func<SomeEntity, bool>> expression = e => e.PartitionKey == dto.SomeId && e.RowKey.CompareTo("YourRowKeyValue") > 0;

The CompareTo method returns a value indicating whether a specified String is less than, equal to, or greater than this instance.

Remember, Azure Table Storage supports querying records by a partial RowKey (in addition to the PartitionKey). For example, if your RowKey values contain words and you only want to filter the words starting with ‘a’ and ‘b’, you would add to your query: (RowKey ge 'a' and RowKey lt 'c'). This means (RowKey >= 'a' && RowKey < 'c'). https://stackoverflow.com/questions/38834919/filter-azure-table-storage-by-rowkey-and-startswith-using-the-python-sdk

I hope this helps! Please let me know if you have any other questions or need further clarification.

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