Use DescribeTable with an Amazon SDK or CLI - Amazon DynamoDB
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Use DescribeTable with an Amazon SDK or CLI

The following code examples show how to use DescribeTable.

Action examples are code excerpts from larger programs and must be run in context. You can see this action in context in the following code example:

.NET
Amazon SDK for .NET
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

private static async Task GetTableInformation() { Console.WriteLine("\n*** Retrieving table information ***"); var response = await Client.DescribeTableAsync(new DescribeTableRequest { TableName = ExampleTableName }); var table = response.Table; Console.WriteLine($"Name: {table.TableName}"); Console.WriteLine($"# of items: {table.ItemCount}"); Console.WriteLine($"Provision Throughput (reads/sec): " + $"{table.ProvisionedThroughput.ReadCapacityUnits}"); Console.WriteLine($"Provision Throughput (writes/sec): " + $"{table.ProvisionedThroughput.WriteCapacityUnits}"); }
  • For API details, see DescribeTable in Amazon SDK for .NET API Reference.

Bash
Amazon CLI with Bash script
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

############################################################################### # function dynamodb_describe_table # # This function returns the status of a DynamoDB table. # # Parameters: # -n table_name -- The name of the table. # # Response: # - TableStatus: # And: # 0 - Table is active. # 1 - If it fails. ############################################################################### function dynamodb_describe_table { local table_name local option OPTARG # Required to use getopts command in a function. ####################################### # Function usage explanation ####################################### function usage() { echo "function dynamodb_describe_table" echo "Describe the status of a DynamoDB table." echo " -n table_name -- The name of the table." echo "" } # Retrieve the calling parameters. while getopts "n:h" option; do case "${option}" in n) table_name="${OPTARG}" ;; h) usage return 0 ;; \?) echo "Invalid parameter" usage return 1 ;; esac done export OPTIND=1 if [[ -z "$table_name" ]]; then errecho "ERROR: You must provide a table name with the -n parameter." usage return 1 fi local table_status table_status=$( aws dynamodb describe-table \ --table-name "$table_name" \ --output text \ --query 'Table.TableStatus' ) local error_code=${?} if [[ $error_code -ne 0 ]]; then aws_cli_error_log "$error_code" errecho "ERROR: AWS reports describe-table operation failed.$table_status" return 1 fi echo "$table_status" return 0 }

The utility functions used in this example.

############################################################################### # function errecho # # This function outputs everything sent to it to STDERR (standard error output). ############################################################################### function errecho() { printf "%s\n" "$*" 1>&2 } ############################################################################## # function aws_cli_error_log() # # This function is used to log the error messages from the AWS CLI. # # See https://docs.aws.amazon.com/cli/latest/topic/return-codes.html#cli-aws-help-return-codes. # # The function expects the following argument: # $1 - The error code returned by the AWS CLI. # # Returns: # 0: - Success. # ############################################################################## function aws_cli_error_log() { local err_code=$1 errecho "Error code : $err_code" if [ "$err_code" == 1 ]; then errecho " One or more S3 transfers failed." elif [ "$err_code" == 2 ]; then errecho " Command line failed to parse." elif [ "$err_code" == 130 ]; then errecho " Process received SIGINT." elif [ "$err_code" == 252 ]; then errecho " Command syntax invalid." elif [ "$err_code" == 253 ]; then errecho " The system environment or configuration was invalid." elif [ "$err_code" == 254 ]; then errecho " The service returned an error." elif [ "$err_code" == 255 ]; then errecho " 255 is a catch-all error." fi return 0 }
  • For API details, see DescribeTable in Amazon CLI Command Reference.

C++
SDK for C++
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

//! Describe an Amazon DynamoDB table. /*! \sa describeTable() \param tableName: The DynamoDB table name. \param clientConfiguration: AWS client configuration. \return bool: Function succeeded. */ bool AwsDoc::DynamoDB::describeTable(const Aws::String &tableName, const Aws::Client::ClientConfiguration &clientConfiguration) { Aws::DynamoDB::DynamoDBClient dynamoClient(clientConfiguration); Aws::DynamoDB::Model::DescribeTableRequest request; request.SetTableName(tableName); const Aws::DynamoDB::Model::DescribeTableOutcome &outcome = dynamoClient.DescribeTable( request); if (outcome.IsSuccess()) { const Aws::DynamoDB::Model::TableDescription &td = outcome.GetResult().GetTable(); std::cout << "Table name : " << td.GetTableName() << std::endl; std::cout << "Table ARN : " << td.GetTableArn() << std::endl; std::cout << "Status : " << Aws::DynamoDB::Model::TableStatusMapper::GetNameForTableStatus( td.GetTableStatus()) << std::endl; std::cout << "Item count : " << td.GetItemCount() << std::endl; std::cout << "Size (bytes): " << td.GetTableSizeBytes() << std::endl; const Aws::DynamoDB::Model::ProvisionedThroughputDescription &ptd = td.GetProvisionedThroughput(); std::cout << "Throughput" << std::endl; std::cout << " Read Capacity : " << ptd.GetReadCapacityUnits() << std::endl; std::cout << " Write Capacity: " << ptd.GetWriteCapacityUnits() << std::endl; const Aws::Vector<Aws::DynamoDB::Model::AttributeDefinition> &ad = td.GetAttributeDefinitions(); std::cout << "Attributes" << std::endl; for (const auto &a: ad) std::cout << " " << a.GetAttributeName() << " (" << Aws::DynamoDB::Model::ScalarAttributeTypeMapper::GetNameForScalarAttributeType( a.GetAttributeType()) << ")" << std::endl; } else { std::cerr << "Failed to describe table: " << outcome.GetError().GetMessage(); } return outcome.IsSuccess(); }
  • For API details, see DescribeTable in Amazon SDK for C++ API Reference.

CLI
Amazon CLI

To describe a table

The following describe-table example describes the MusicCollection table.

aws dynamodb describe-table \ --table-name MusicCollection

Output:

{ "Table": { "AttributeDefinitions": [ { "AttributeName": "Artist", "AttributeType": "S" }, { "AttributeName": "SongTitle", "AttributeType": "S" } ], "ProvisionedThroughput": { "NumberOfDecreasesToday": 0, "WriteCapacityUnits": 5, "ReadCapacityUnits": 5 }, "TableSizeBytes": 0, "TableName": "MusicCollection", "TableStatus": "ACTIVE", "KeySchema": [ { "KeyType": "HASH", "AttributeName": "Artist" }, { "KeyType": "RANGE", "AttributeName": "SongTitle" } ], "ItemCount": 0, "CreationDateTime": 1421866952.062 } }

For more information, see Describing a Table in the Amazon DynamoDB Developer Guide.

  • For API details, see DescribeTable in Amazon CLI Command Reference.

Go
SDK for Go V2
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

import ( "context" "errors" "log" "time" "github.com/aws/aws-sdk-go-v2/aws" "github.com/aws/aws-sdk-go-v2/feature/dynamodb/attributevalue" "github.com/aws/aws-sdk-go-v2/feature/dynamodb/expression" "github.com/aws/aws-sdk-go-v2/service/dynamodb" "github.com/aws/aws-sdk-go-v2/service/dynamodb/types" ) // TableBasics encapsulates the Amazon DynamoDB service actions used in the examples. // It contains a DynamoDB service client that is used to act on the specified table. type TableBasics struct { DynamoDbClient *dynamodb.Client TableName string } // TableExists determines whether a DynamoDB table exists. func (basics TableBasics) TableExists(ctx context.Context) (bool, error) { exists := true _, err := basics.DynamoDbClient.DescribeTable( ctx, &dynamodb.DescribeTableInput{TableName: aws.String(basics.TableName)}, ) if err != nil { var notFoundEx *types.ResourceNotFoundException if errors.As(err, &notFoundEx) { log.Printf("Table %v does not exist.\n", basics.TableName) err = nil } else { log.Printf("Couldn't determine existence of table %v. Here's why: %v\n", basics.TableName, err) } exists = false } return exists, err }
  • For API details, see DescribeTable in Amazon SDK for Go API Reference.

Java
SDK for Java 2.x
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeDefinition; import software.amazon.awssdk.services.dynamodb.model.DescribeTableRequest; import software.amazon.awssdk.services.dynamodb.model.ProvisionedThroughputDescription; import software.amazon.awssdk.services.dynamodb.model.TableDescription; import java.util.List; /** * Before running this Java V2 code example, set up your development * environment, including your credentials. * * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class DescribeTable { public static void main(String[] args) { final String usage = """ Usage: <tableName> Where: tableName - The Amazon DynamoDB table to get information about (for example, Music3). """; if (args.length != 1) { System.out.println(usage); System.exit(1); } String tableName = args[0]; System.out.format("Getting description for %s\n\n", tableName); Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); describeDymamoDBTable(ddb, tableName); ddb.close(); } public static void describeDymamoDBTable(DynamoDbClient ddb, String tableName) { DescribeTableRequest request = DescribeTableRequest.builder() .tableName(tableName) .build(); try { TableDescription tableInfo = ddb.describeTable(request).table(); if (tableInfo != null) { System.out.format("Table name : %s\n", tableInfo.tableName()); System.out.format("Table ARN : %s\n", tableInfo.tableArn()); System.out.format("Status : %s\n", tableInfo.tableStatus()); System.out.format("Item count : %d\n", tableInfo.itemCount()); System.out.format("Size (bytes): %d\n", tableInfo.tableSizeBytes()); ProvisionedThroughputDescription throughputInfo = tableInfo.provisionedThroughput(); System.out.println("Throughput"); System.out.format(" Read Capacity : %d\n", throughputInfo.readCapacityUnits()); System.out.format(" Write Capacity: %d\n", throughputInfo.writeCapacityUnits()); List<AttributeDefinition> attributes = tableInfo.attributeDefinitions(); System.out.println("Attributes"); for (AttributeDefinition a : attributes) { System.out.format(" %s (%s)\n", a.attributeName(), a.attributeType()); } } } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } System.out.println("\nDone!"); } }
  • For API details, see DescribeTable in Amazon SDK for Java 2.x API Reference.

JavaScript
SDK for JavaScript (v3)
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

import { DescribeTableCommand, DynamoDBClient } from "@aws-sdk/client-dynamodb"; const client = new DynamoDBClient({}); export const main = async () => { const command = new DescribeTableCommand({ TableName: "Pastries", }); const response = await client.send(command); console.log(`TABLE NAME: ${response.Table.TableName}`); console.log(`TABLE ITEM COUNT: ${response.Table.ItemCount}`); return response; };
SDK for JavaScript (v2)
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

// Load the AWS SDK for Node.js var AWS = require("aws-sdk"); // Set the region AWS.config.update({ region: "REGION" }); // Create the DynamoDB service object var ddb = new AWS.DynamoDB({ apiVersion: "2012-08-10" }); var params = { TableName: process.argv[2], }; // Call DynamoDB to retrieve the selected table descriptions ddb.describeTable(params, function (err, data) { if (err) { console.log("Error", err); } else { console.log("Success", data.Table.KeySchema); } });
PowerShell
Tools for PowerShell

Example 1: Returns details of the specified table.

Get-DDBTable -TableName "myTable"
  • For API details, see DescribeTable in Amazon Tools for PowerShell Cmdlet Reference.

Python
SDK for Python (Boto3)
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

class Movies: """Encapsulates an Amazon DynamoDB table of movie data. Example data structure for a movie record in this table: { "year": 1999, "title": "For Love of the Game", "info": { "directors": ["Sam Raimi"], "release_date": "1999-09-15T00:00:00Z", "rating": 6.3, "plot": "A washed up pitcher flashes through his career.", "rank": 4987, "running_time_secs": 8220, "actors": [ "Kevin Costner", "Kelly Preston", "John C. Reilly" ] } } """ def __init__(self, dyn_resource): """ :param dyn_resource: A Boto3 DynamoDB resource. """ self.dyn_resource = dyn_resource # The table variable is set during the scenario in the call to # 'exists' if the table exists. Otherwise, it is set by 'create_table'. self.table = None def exists(self, table_name): """ Determines whether a table exists. As a side effect, stores the table in a member variable. :param table_name: The name of the table to check. :return: True when the table exists; otherwise, False. """ try: table = self.dyn_resource.Table(table_name) table.load() exists = True except ClientError as err: if err.response["Error"]["Code"] == "ResourceNotFoundException": exists = False else: logger.error( "Couldn't check for existence of %s. Here's why: %s: %s", table_name, err.response["Error"]["Code"], err.response["Error"]["Message"], ) raise else: self.table = table return exists
  • For API details, see DescribeTable in Amazon SDK for Python (Boto3) API Reference.

Ruby
SDK for Ruby
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

# Encapsulates an Amazon DynamoDB table of movie data. class Scaffold attr_reader :dynamo_resource, :table_name, :table def initialize(table_name) client = Aws::DynamoDB::Client.new(region: 'us-east-1') @dynamo_resource = Aws::DynamoDB::Resource.new(client: client) @table_name = table_name @table = nil @logger = Logger.new($stdout) @logger.level = Logger::DEBUG end # Determines whether a table exists. As a side effect, stores the table in # a member variable. # # @param table_name [String] The name of the table to check. # @return [Boolean] True when the table exists; otherwise, False. def exists?(table_name) @dynamo_resource.client.describe_table(table_name: table_name) @logger.debug("Table #{table_name} exists") rescue Aws::DynamoDB::Errors::ResourceNotFoundException @logger.debug("Table #{table_name} doesn't exist") false rescue Aws::DynamoDB::Errors::ServiceError => e puts("Couldn't check for existence of #{table_name}:\n") puts("\t#{e.code}: #{e.message}") raise end
  • For API details, see DescribeTable in Amazon SDK for Ruby API Reference.

SAP ABAP
SDK for SAP ABAP
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

TRY. oo_result = lo_dyn->describetable( iv_tablename = iv_table_name ). DATA(lv_tablename) = oo_result->get_table( )->ask_tablename( ). DATA(lv_tablearn) = oo_result->get_table( )->ask_tablearn( ). DATA(lv_tablestatus) = oo_result->get_table( )->ask_tablestatus( ). DATA(lv_itemcount) = oo_result->get_table( )->ask_itemcount( ). MESSAGE 'The table name is ' && lv_tablename && '. The table ARN is ' && lv_tablearn && '. The tablestatus is ' && lv_tablestatus && '. Item count is ' && lv_itemcount TYPE 'I'. CATCH /aws1/cx_dynresourcenotfoundex. MESSAGE 'The table ' && lv_tablename && ' does not exist' TYPE 'E'. ENDTRY.
  • For API details, see DescribeTable in Amazon SDK for SAP ABAP API reference.

For a complete list of Amazon SDK developer guides and code examples, see Using DynamoDB with an Amazon SDK. This topic also includes information about getting started and details about previous SDK versions.