The following code examples show how to:
Get an item by running a SELECT statement.
Add an item by running an INSERT statement.
Update an item by running an UPDATE statement.
Delete an item by running a DELETE statement.
- AWS SDK for .NET
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Note
There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository
. namespace PartiQL_Basics_Scenario { public class PartiQLMethods { private static readonly AmazonDynamoDBClient Client = new AmazonDynamoDBClient(); /// <summary> /// Inserts movies imported from a JSON file into the movie table by /// using an Amazon DynamoDB PartiQL INSERT statement. /// </summary> /// <param name="tableName">The name of the table where the movie /// information will be inserted.</param> /// <param name="movieFileName">The name of the JSON file that contains /// movie information.</param> /// <returns>A Boolean value that indicates the success or failure of /// the insert operation.</returns> public static async Task<bool> InsertMovies(string tableName, string movieFileName) { // Get the list of movies from the JSON file. var movies = ImportMovies(movieFileName); var success = false; if (movies is not null) { // Insert the movies in a batch using PartiQL. Because the // batch can contain a maximum of 25 items, insert 25 movies // at a time. string insertBatch = $"INSERT INTO {tableName} VALUE {{'title': ?, 'year': ?}}"; var statements = new List<BatchStatementRequest>(); try { for (var indexOffset = 0; indexOffset < 250; indexOffset += 25) { for (var i = indexOffset; i < indexOffset + 25; i++) { statements.Add(new BatchStatementRequest { Statement = insertBatch, Parameters = new List<AttributeValue> { new AttributeValue { S = movies[i].Title }, new AttributeValue { N = movies[i].Year.ToString() }, }, }); } var response = await Client.BatchExecuteStatementAsync(new BatchExecuteStatementRequest { Statements = statements, }); // Wait between batches for movies to be successfully added. System.Threading.Thread.Sleep(3000); success = response.HttpStatusCode == System.Net.HttpStatusCode.OK; // Clear the list of statements for the next batch. statements.Clear(); } } catch (AmazonDynamoDBException ex) { Console.WriteLine(ex.Message); } } return success; } /// <summary> /// Loads the contents of a JSON file into a list of movies to be /// added to the DynamoDB table. /// </summary> /// <param name="movieFileName">The full path to the JSON file.</param> /// <returns>A generic list of movie objects.</returns> public static List<Movie> ImportMovies(string movieFileName) { if (!File.Exists(movieFileName)) { return null!; } using var sr = new StreamReader(movieFileName); string json = sr.ReadToEnd(); var allMovies = JsonConvert.DeserializeObject<List<Movie>>(json); if (allMovies is not null) { // Return the first 250 entries. return allMovies.GetRange(0, 250); } else { return null!; } } /// <summary> /// Uses a PartiQL SELECT statement to retrieve a single movie from the /// movie database. /// </summary> /// <param name="tableName">The name of the movie table.</param> /// <param name="movieTitle">The title of the movie to retrieve.</param> /// <returns>A list of movie data. If no movie matches the supplied /// title, the list is empty.</returns> public static async Task<List<Dictionary<string, AttributeValue>>> GetSingleMovie(string tableName, string movieTitle) { string selectSingle = $"SELECT * FROM {tableName} WHERE title = ?"; var parameters = new List<AttributeValue> { new AttributeValue { S = movieTitle }, }; var response = await Client.ExecuteStatementAsync(new ExecuteStatementRequest { Statement = selectSingle, Parameters = parameters, }); return response.Items; } /// <summary> /// Retrieve multiple movies by year using a SELECT statement. /// </summary> /// <param name="tableName">The name of the movie table.</param> /// <param name="year">The year the movies were released.</param> /// <returns></returns> public static async Task<List<Dictionary<string, AttributeValue>>> GetMovies(string tableName, int year) { string selectSingle = $"SELECT * FROM {tableName} WHERE year = ?"; var parameters = new List<AttributeValue> { new AttributeValue { N = year.ToString() }, }; var response = await Client.ExecuteStatementAsync(new ExecuteStatementRequest { Statement = selectSingle, Parameters = parameters, }); return response.Items; } /// <summary> /// Inserts a single movie into the movies table. /// </summary> /// <param name="tableName">The name of the table.</param> /// <param name="movieTitle">The title of the movie to insert.</param> /// <param name="year">The year that the movie was released.</param> /// <returns>A Boolean value that indicates the success or failure of /// the INSERT operation.</returns> public static async Task<bool> InsertSingleMovie(string tableName, string movieTitle, int year) { string insertBatch = $"INSERT INTO {tableName} VALUE {{'title': ?, 'year': ?}}"; var response = await Client.ExecuteStatementAsync(new ExecuteStatementRequest { Statement = insertBatch, Parameters = new List<AttributeValue> { new AttributeValue { S = movieTitle }, new AttributeValue { N = year.ToString() }, }, }); return response.HttpStatusCode == System.Net.HttpStatusCode.OK; } /// <summary> /// Updates a single movie in the table, adding information for the /// producer. /// </summary> /// <param name="tableName">the name of the table.</param> /// <param name="producer">The name of the producer.</param> /// <param name="movieTitle">The movie title.</param> /// <param name="year">The year the movie was released.</param> /// <returns>A Boolean value that indicates the success of the /// UPDATE operation.</returns> public static async Task<bool> UpdateSingleMovie(string tableName, string producer, string movieTitle, int year) { string insertSingle = $"UPDATE {tableName} SET Producer=? WHERE title = ? AND year = ?"; var response = await Client.ExecuteStatementAsync(new ExecuteStatementRequest { Statement = insertSingle, Parameters = new List<AttributeValue> { new AttributeValue { S = producer }, new AttributeValue { S = movieTitle }, new AttributeValue { N = year.ToString() }, }, }); return response.HttpStatusCode == System.Net.HttpStatusCode.OK; } /// <summary> /// Deletes a single movie from the table. /// </summary> /// <param name="tableName">The name of the table.</param> /// <param name="movieTitle">The title of the movie to delete.</param> /// <param name="year">The year that the movie was released.</param> /// <returns>A Boolean value that indicates the success of the /// DELETE operation.</returns> public static async Task<bool> DeleteSingleMovie(string tableName, string movieTitle, int year) { var deleteSingle = $"DELETE FROM {tableName} WHERE title = ? AND year = ?"; var response = await Client.ExecuteStatementAsync(new ExecuteStatementRequest { Statement = deleteSingle, Parameters = new List<AttributeValue> { new AttributeValue { S = movieTitle }, new AttributeValue { N = year.ToString() }, }, }); return response.HttpStatusCode == System.Net.HttpStatusCode.OK; } /// <summary> /// Displays the list of movies returned from a database query. /// </summary> /// <param name="items">The list of movie information to display.</param> private static void DisplayMovies(List<Dictionary<string, AttributeValue>> items) { if (items.Count > 0) { Console.WriteLine($"Found {items.Count} movies."); items.ForEach(item => Console.WriteLine($"{item["year"].N}\t{item["title"].S}")); } else { Console.WriteLine($"Didn't find a movie that matched the supplied criteria."); } } } } /// <summary> /// Uses a PartiQL SELECT statement to retrieve a single movie from the /// movie database. /// </summary> /// <param name="tableName">The name of the movie table.</param> /// <param name="movieTitle">The title of the movie to retrieve.</param> /// <returns>A list of movie data. If no movie matches the supplied /// title, the list is empty.</returns> public static async Task<List<Dictionary<string, AttributeValue>>> GetSingleMovie(string tableName, string movieTitle) { string selectSingle = $"SELECT * FROM {tableName} WHERE title = ?"; var parameters = new List<AttributeValue> { new AttributeValue { S = movieTitle }, }; var response = await Client.ExecuteStatementAsync(new ExecuteStatementRequest { Statement = selectSingle, Parameters = parameters, }); return response.Items; } /// <summary> /// Inserts a single movie into the movies table. /// </summary> /// <param name="tableName">The name of the table.</param> /// <param name="movieTitle">The title of the movie to insert.</param> /// <param name="year">The year that the movie was released.</param> /// <returns>A Boolean value that indicates the success or failure of /// the INSERT operation.</returns> public static async Task<bool> InsertSingleMovie(string tableName, string movieTitle, int year) { string insertBatch = $"INSERT INTO {tableName} VALUE {{'title': ?, 'year': ?}}"; var response = await Client.ExecuteStatementAsync(new ExecuteStatementRequest { Statement = insertBatch, Parameters = new List<AttributeValue> { new AttributeValue { S = movieTitle }, new AttributeValue { N = year.ToString() }, }, }); return response.HttpStatusCode == System.Net.HttpStatusCode.OK; } /// <summary> /// Updates a single movie in the table, adding information for the /// producer. /// </summary> /// <param name="tableName">the name of the table.</param> /// <param name="producer">The name of the producer.</param> /// <param name="movieTitle">The movie title.</param> /// <param name="year">The year the movie was released.</param> /// <returns>A Boolean value that indicates the success of the /// UPDATE operation.</returns> public static async Task<bool> UpdateSingleMovie(string tableName, string producer, string movieTitle, int year) { string insertSingle = $"UPDATE {tableName} SET Producer=? WHERE title = ? AND year = ?"; var response = await Client.ExecuteStatementAsync(new ExecuteStatementRequest { Statement = insertSingle, Parameters = new List<AttributeValue> { new AttributeValue { S = producer }, new AttributeValue { S = movieTitle }, new AttributeValue { N = year.ToString() }, }, }); return response.HttpStatusCode == System.Net.HttpStatusCode.OK; } /// <summary> /// Deletes a single movie from the table. /// </summary> /// <param name="tableName">The name of the table.</param> /// <param name="movieTitle">The title of the movie to delete.</param> /// <param name="year">The year that the movie was released.</param> /// <returns>A Boolean value that indicates the success of the /// DELETE operation.</returns> public static async Task<bool> DeleteSingleMovie(string tableName, string movieTitle, int year) { var deleteSingle = $"DELETE FROM {tableName} WHERE title = ? AND year = ?"; var response = await Client.ExecuteStatementAsync(new ExecuteStatementRequest { Statement = deleteSingle, Parameters = new List<AttributeValue> { new AttributeValue { S = movieTitle }, new AttributeValue { N = year.ToString() }, }, }); return response.HttpStatusCode == System.Net.HttpStatusCode.OK; }-
For API details, see ExecuteStatement in AWS SDK for .NET API Reference.
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For a complete list of AWS SDK developer guides and code examples, see Using DynamoDB with an AWS SDK. This topic also includes information about getting started and details about previous SDK versions.
