BLOB type (C#)

Use the blob type for binary data.

Although you can store binary-encoded vector data in a blob column, you cannot create a vector index or perform a vector search on the column. Instead, use the vector type to store vector data.

Due to a known issue with filtering on blob, DataStax does not recommend using blob in primary keys.

You can insert binary data as a byte array.

The C# client automatically converts byte[] values into a Base64-encoded string.

Typed

using DataStax.AstraDB.DataApi;
using DataStax.AstraDB.DataApi.Core;
using DataStax.AstraDB.DataApi.Tables;

namespace Examples;

public class ExampleRow
{
  [ColumnPrimaryKey]
  [ColumnName("title")]
  public string Title { get; set; } = null!;

  [ColumnName("example_blob")]
  public byte[]? ExampleBlob { get; set; }
}

public class Program
{
  static async Task Main()
  {
    // Get an existing table
    var client = new DataAPIClient(
      new CommandOptions() { Destination = DataAPIDestination.HCD }
    );

    var database = client.GetDatabase(
      "API_ENDPOINT",
      DataAPIClient.UsernamePasswordTokenProvider(
        "USERNAME",
        "PASSWORD"
      ),
      "KEYSPACE_NAME"
    );

    var table = database.GetTable<ExampleRow>("TABLE_NAME");

    // Insert a binary value
    var row = new ExampleRow()
    {
      ExampleBlob = new byte[]
      {
        0x3D,
        0xFB,
        0xE7,
        0x6D,
        0x3E,
        0xE9,
        0x78,
        0xD5,
        0x3F,
        0x49,
        0xFB,
        0xE7,
      },
      Title = "Example",
    };

    await table.InsertOneAsync(row);
  }
}

Untyped

using DataStax.AstraDB.DataApi;
using DataStax.AstraDB.DataApi.Core;
using DataStax.AstraDB.DataApi.Tables;

namespace Examples;

public class Program
{
  static async Task Main()
  {
    // Get an existing table
    var client = new DataAPIClient(
      new CommandOptions() { Destination = DataAPIDestination.HCD }
    );

    var database = client.GetDatabase(
      "API_ENDPOINT",
      DataAPIClient.UsernamePasswordTokenProvider(
        "USERNAME",
        "PASSWORD"
      ),
      "KEYSPACE_NAME"
    );

    var table = database.GetTable("TABLE_NAME");

    // Insert a binary value
    var row = new Row()
    {
      {
        "example_blob",
        new byte[]
        {
          0x3D,
          0xFB,
          0xE7,
          0x6D,
          0x3E,
          0xE9,
          0x78,
          0xD5,
          0x3F,
          0x49,
          0xFB,
          0xE7,
        }
      },
      { "title", "Example" },
    };

    await table.InsertOneAsync(row);
  }
}

BLOB type (C#)

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