Insert a row (C#)

Inserts a single row into a table.

This method can insert a row in an existing CQL table, but the Data API does not support all CQL data types or modifiers. For more information, see Data type compatibility in tables (C#).

For general information about working with tables and rows, see About tables with the Data API (C#).

Ready to write code? See the examples for this method to get started. If you are new to the Data API, check out the quickstart.

Result

Inserts the specified row and returns a TableInsertOneResult instance that includes the primary key of the inserted row and the schema of the primary key.

If a row with the specified primary key already exists in the table, the row will be overwritten with the specified column values. Unspecified columns will remain unchanged.

If any of the inserted columns use the wrong datatype or improper encoding, then the entire insert fails.

Parameters

Use the InsertOneAsync method, which belongs to the Table class. You can also use InsertOne, which is the synchronous version of the method.

Method signature 
public Task<TableInsertOneResult> InsertOneAsync(
  T row, TableInsertOneOptions options = null
);
Name Type Summary

row

T

An object that defines the row to insert.

All primary key values are required. If you use a custom class, any unspecified columns are set to null.

The table definition determines the columns in the row, the type for each column, and the primary key. To get this information, see List table metadata (C#).

options

TableInsertOneOptions

Optional. General API options for this operation, including the timeout. For more information and examples, see Customize API interaction.

Examples

The following examples demonstrate how to insert a row into a table.

Insert a row

When you insert a row, you must specify a non-null value for each primary key column. Non-primary key columns are optional. To reduce tombstones, you should not explicitly set a column to null.

  • Typed

  • Untyped

You can manually define a client-side type for your table to help statically catch errors. For more information and examples, see Custom typing for tables.

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

namespace Examples;

public class Book
{
  [ColumnPrimaryKey(1)]
  [ColumnName("title")]
  public string Title { get; set; } = null!;

  [ColumnPrimaryKey(2)]
  [ColumnName("author")]
  public string Author { get; set; } = null!;

  [ColumnName("number_of_pages")]
  public int? NumberOfPages { get; set; }

  [ColumnName("genres")]
  public HashSet<string>? Genres { get; set; }

  [ColumnName("due_date")]
  public DateOnly? DueDate { get; set; }
}

public class Program
{
  static async Task Main()
  {
    // Get an existing table
    var client = new DataAPIClient();
    var database = client.GetDatabase(
      "API_ENDPOINT",
      "APPLICATION_TOKEN"
    );
    var table = database.GetTable<Book>("TABLE_NAME");

    // Insert a row into the table
    var row = new Book()
    {
      Title = "Computed Wilderness",
      Author = "Ryan Eau",
      NumberOfPages = 432,
      DueDate = new DateOnly(2024, 12, 18),
      Genres = new HashSet<string> { "History", "Biography" },
    };

    await table.InsertOneAsync(row);
  }
}

If you don’t pass a type parameter, the collection or table remains untyped. This is a more flexible but less type-safe option.

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

namespace Examples;

public class Program
{
  static async Task Main()
  {
    // Get an existing table
    var client = new DataAPIClient();
    var database = client.GetDatabase(
      "API_ENDPOINT",
      "APPLICATION_TOKEN"
    );
    var table = database.GetTable("TABLE_NAME");

    // Insert a row into the table
    var row = new Row()
    {
      { "title", "Computed Wilderness" },
      { "author", "Ryan Eau" },
      { "number_of_pages", 432 },
      { "due_date", new DateOnly(2024, 12, 18) },
      {
        "genres",
        new HashSet<string> { "History", "Biography" }
      },
    };

    await table.InsertOneAsync(row);
  }
}

Insert a row with vector embeddings

You can only insert vector embeddings into vector columns.

To create a table with a vector column, see Create a table (C#). To add a vector column to an existing table, see Alter a table (C#).

All embeddings in the column should use the same provider, model, and dimensions. Mismatched embeddings can cause inaccurate vector searches.

The C# client automatically encodes your vector embeddings when you insert to a vector column.

  • Typed

  • Untyped

You can manually define a client-side type for your table to help statically catch errors. For more information and examples, see Custom typing for tables.

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

namespace Examples;

public class Book
{
  [ColumnPrimaryKey(1)]
  [ColumnName("title")]
  public string Title { get; set; } = null!;

  [ColumnPrimaryKey(2)]
  [ColumnName("author")]
  public string Author { get; set; } = null!;

  [ColumnVector(3)]
  [ColumnName("summary_genres_vector")]
  public double[]? SummaryGenresVector { get; set; }
}

public class Program
{
  static async Task Main()
  {
    // Get an existing table
    var client = new DataAPIClient();
    var database = client.GetDatabase(
      "API_ENDPOINT",
      "APPLICATION_TOKEN"
    );
    var table = database.GetTable<Book>("TABLE_NAME");

    // Insert a row into the table
    var embeddings = new double[] { 0.08f, -0.62f, 0.39f };
    var row = new Book()
    {
      Title = "Computed Wilderness",
      Author = "Ryan Eau",
      SummaryGenresVector = embeddings,
    };

    await table.InsertOneAsync(row);
  }
}

If you don’t pass a type parameter, the collection or table remains untyped. This is a more flexible but less type-safe option.

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

namespace Examples;

public class Program
{
  static async Task Main()
  {
    // Get an existing table
    var client = new DataAPIClient();
    var database = client.GetDatabase(
      "API_ENDPOINT",
      "APPLICATION_TOKEN"
    );
    var table = database.GetTable("TABLE_NAME");

    // Insert a row into the table
    var embeddings = new double[] { 0.08f, -0.62f, 0.39f };
    var row = new Row()
    {
      { "title", "Computed Wilderness" },
      { "author", "Ryan Eau" },
      { "summary_genres_vector", embeddings },
    };

    await table.InsertOneAsync(row);
  }
}

Insert a row and generate vector embeddings

To automatically generate vector embeddings, your table must have a vector column with an embedding provider integration. You can configure embedding provider integrations when you create a table, add a vector column to an existing table, or alter an existing vector column.

When you insert a row, you can pass a string to the vector column. Astra DB uses the embedding provider integration to generate vector embeddings from that string.

The strings used to generate the vector embeddings are not stored. If you want to store the original strings, you must store them in a separate column.

In the following examples, summary_genres_vector is a vector column that has an embedding provider integration configured, and summary_genres_original_text is a text column to store the original text.

  • Typed

  • Untyped

You can manually define a client-side type for your table to help statically catch errors. For more information and examples, see Custom typing for tables.

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

namespace Examples;

public class Book
{
  [ColumnPrimaryKey(1)]
  [ColumnName("title")]
  public string Title { get; set; } = null!;

  [ColumnPrimaryKey(2)]
  [ColumnName("author")]
  public string Author { get; set; } = null!;

  [ColumnVectorize(
    provider: "nvidia",
    modelName: "nvidia/nv-embedqa-e5-v5",
    dimension: 1024
  )]
  [ColumnName("summary_genres_vector")]
  public object? SummaryGenresVector { get; set; }

  [ColumnName("summary_genres_original_text")]
  public string? SummaryGenresOriginalText { get; set; }
}

public class Program
{
  static async Task Main()
  {
    // Get an existing table
    var client = new DataAPIClient();
    var database = client.GetDatabase(
      "API_ENDPOINT",
      "APPLICATION_TOKEN"
    );
    var table = database.GetTable<Book>("TABLE_NAME");

    // Insert a row into the table
    var row = new Book()
    {
      Title = "Computed Wilderness",
      Author = "Ryan Eau",
      SummaryGenresVector = "Text to vectorize",
      SummaryGenresOriginalText = "Text to vectorize",
    };

    await table.InsertOneAsync(row);
  }
}

If you don’t pass a type parameter, the collection or table remains untyped. This is a more flexible but less type-safe option.

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

namespace Examples;

public class Program
{
  static async Task Main()
  {
    // Get an existing table
    var client = new DataAPIClient();
    var database = client.GetDatabase(
      "API_ENDPOINT",
      "APPLICATION_TOKEN"
    );
    var table = database.GetTable("TABLE_NAME");

    // Insert a row into the table
    var row = new Row()
    {
      { "title", "Computed Wilderness" },
      { "author", "Ryan Eau" },
      { "summary_genres_vector", "Text to vectorize" },
      { "summary_genres_original_text", "Text to vectorize" },
    };

    await table.InsertOneAsync(row);
  }
}

Insert a row with a map column that uses non-string keys

The C# client supports insertion of a row with a map column that includes non-string keys. (You don’t need to use an array of key-value pairs to represent the map column.)

  • Typed

  • Untyped

You can manually define a client-side type for your collection to help statically catch errors. For more information and examples, see Custom typing for collections.

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

namespace Examples;

public class Book
{
  [ColumnPrimaryKey(1)]
  [ColumnName("title")]
  public string? Title { get; set; }

  [ColumnPrimaryKey(2)]
  [ColumnName("author")]
  public string? Author { get; set; }

  [ColumnName("map_column_int_str")]
  public Dictionary<int, string>? MapColumnIntStr { get; set; }

  [ColumnName("map_column_str_str")]
  public Dictionary<string, string>? MapColumnStrStr { get; set; }
}

public class Program
{
  static async Task Main()
  {
    // Get an existing table
    var client = new DataAPIClient();
    var database = client.GetDatabase(
      "API_ENDPOINT",
      "APPLICATION_TOKEN"
    );
    var table = database.GetTable<Book>("TABLE_NAME");

    // Insert a row into the table
    var row = new Book()
    {
      MapColumnIntStr = new Dictionary<int, string>
      {
        { 1, "value1" },
        { 2, "value2" },
      },
      MapColumnStrStr = new Dictionary<string, string>
      {
        { "key1", "value1" },
        { "key2", "value2" },
      },
      Title = "Once in a Living Memory",
      Author = "Kayla McMaster",
    };

    await table.InsertOneAsync(row);
  }
}

If you don’t pass a type parameter, the collection or table remains untyped. This is a more flexible but less type-safe option.

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

namespace Examples;

public class Program
{
  static async Task Main()
  {
    // Get an existing table
    var client = new DataAPIClient();
    var database = client.GetDatabase(
      "API_ENDPOINT",
      "APPLICATION_TOKEN"
    );
    var table = database.GetTable("TABLE_NAME");

    // Insert a row into the table
    var row = new Row()
    {
      {
        "map_column_int_str",
        new Dictionary<int, string> { { 1, "value1" }, { 2, "value2" } }
      },
      {
        "map_column_str_str",
        new Dictionary<string, string>
        {
          { "key1", "value1" },
          { "key2", "value2" },
        }
      },
      { "title", "Once in a Living Memory" },
      { "author", "Kayla McMaster" },
    };

    await table.InsertOneAsync(row);
  }
}

Client reference

For more information, see the client reference.

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