Use DescribeDBParameters with an Amazon SDK or CLI

    /// <summary>
    /// Get a list of DB parameters from a specific parameter group.
    /// </summary>
    /// <param name="dbParameterGroupName">Name of a specific DB parameter group.</param>
    /// <param name="source">Optional source for selecting parameters.</param>
    /// <returns>List of parameter values.</returns>
    public async Task<List<Parameter>> DescribeDBParameters(string dbParameterGroupName, string source = null)
    {
        var results = new List<Parameter>();
        var paginateParameters = _amazonRDS.Paginators.DescribeDBParameters(
            new DescribeDBParametersRequest()
            {
                DBParameterGroupName = dbParameterGroupName,
                Source = source
            });
        // Get the entire list using the paginator.
        await foreach (var parameters in paginateParameters.Parameters)
        {
            results.Add(parameters);
        }
        return results;
    }

        Aws::Client::ClientConfiguration clientConfig;
        // Optional: Set to the AWS Region (overrides config file).
        // clientConfig.region = "us-east-1";

    Aws::RDS::RDSClient client(clientConfig);


//! Routine which gets DB parameters using the 'DescribeDBParameters' api.
/*!
 \sa getDBParameters()
 \param parameterGroupName: The name of the parameter group.
 \param namePrefix: Prefix string to filter results by parameter name.
 \param source: A source such as 'user', ignored if empty.
 \param parametersResult: Vector of 'Parameter' objects returned by the routine.
 \param client: 'RDSClient' instance.
 \return bool: Successful completion.
 */
bool AwsDoc::RDS::getDBParameters(const Aws::String &parameterGroupName,
                                  const Aws::String &namePrefix,
                                  const Aws::String &source,
                                  Aws::Vector<Aws::RDS::Model::Parameter> &parametersResult,
                                  const Aws::RDS::RDSClient &client) {
    Aws::String marker;
    do {
        Aws::RDS::Model::DescribeDBParametersRequest request;
        request.SetDBParameterGroupName(PARAMETER_GROUP_NAME);
        if (!marker.empty()) {
            request.SetMarker(marker);
        }
        if (!source.empty()) {
            request.SetSource(source);
        }

        Aws::RDS::Model::DescribeDBParametersOutcome outcome =
                client.DescribeDBParameters(request);

        if (outcome.IsSuccess()) {
            const Aws::Vector<Aws::RDS::Model::Parameter> &parameters =
                    outcome.GetResult().GetParameters();
            for (const Aws::RDS::Model::Parameter &parameter: parameters) {
                if (!namePrefix.empty()) {
                    if (parameter.GetParameterName().find(namePrefix) == 0) {
                        parametersResult.push_back(parameter);
                    }
                }
                else {
                    parametersResult.push_back(parameter);
                }
            }

            marker = outcome.GetResult().GetMarker();
        }
        else {
            std::cerr << "Error with RDS::DescribeDBParameters. "
                      << outcome.GetError().GetMessage()
                      << std::endl;
            return false;
        }
    } while (!marker.empty());

    return true;
}

To describe the parameters in a DB parameter group

The following describe-db-parameters example retrieves the details of the specified DB parameter group.

aws rds describe-db-parameters \
    --db-parameter-group-name mydbpg

Output:

{
    "Parameters": [
        {
            "ParameterName": "allow-suspicious-udfs",
            "Description": "Controls whether user-defined functions that have only an xxx symbol for the main function can be loaded",
            "Source": "engine-default",
            "ApplyType": "static",
            "DataType": "boolean",
            "AllowedValues": "0,1",
            "IsModifiable": false,
            "ApplyMethod": "pending-reboot"
        },
        {
            "ParameterName": "auto_generate_certs",
            "Description": "Controls whether the server autogenerates SSL key and certificate files in the data directory, if they do not already exist.",
            "Source": "engine-default",
            "ApplyType": "static",
            "DataType": "boolean",
            "AllowedValues": "0,1",
            "IsModifiable": false,
            "ApplyMethod": "pending-reboot"
        },
        ...some output truncated...
    ]
}

For more information, see Working with DB Parameter Groups in the Amazon RDS User Guide.

type DbInstances struct {
	RdsClient *rds.Client
}



// GetParameters gets the parameters that are contained in a DB parameter group.
func (instances *DbInstances) GetParameters(parameterGroupName string, source string) (
	[]types.Parameter, error) {

	var output *rds.DescribeDBParametersOutput
	var params []types.Parameter
	var err error
	parameterPaginator := rds.NewDescribeDBParametersPaginator(instances.RdsClient,
		&rds.DescribeDBParametersInput{
			DBParameterGroupName: aws.String(parameterGroupName),
			Source:               aws.String(source),
		})
	for parameterPaginator.HasMorePages() {
		output, err = parameterPaginator.NextPage(context.TODO())
		if err != nil {
			log.Printf("Couldn't get parameters for %v: %v\n", parameterGroupName, err)
			break
		} else {
			params = append(params, output.Parameters...)
		}
	}
	return params, err
}

    // Retrieve parameters in the group.
    public static void describeDbParameters(RdsClient rdsClient, String dbGroupName, int flag) {
        try {
            DescribeDbParametersRequest dbParameterGroupsRequest;
            if (flag == 0) {
                dbParameterGroupsRequest = DescribeDbParametersRequest.builder()
                        .dbParameterGroupName(dbGroupName)
                        .build();
            } else {
                dbParameterGroupsRequest = DescribeDbParametersRequest.builder()
                        .dbParameterGroupName(dbGroupName)
                        .source("user")
                        .build();
            }

            DescribeDbParametersResponse response = rdsClient.describeDBParameters(dbParameterGroupsRequest);
            List<Parameter> dbParameters = response.parameters();
            String paraName;
            for (Parameter para : dbParameters) {
                // Only print out information about either auto_increment_offset or
                // auto_increment_increment.
                paraName = para.parameterName();
                if ((paraName.compareTo("auto_increment_offset") == 0)
                        || (paraName.compareTo("auto_increment_increment ") == 0)) {
                    System.out.println("*** The parameter name is  " + paraName);
                    System.out.println("*** The parameter value is  " + para.parameterValue());
                    System.out.println("*** The parameter data type is " + para.dataType());
                    System.out.println("*** The parameter description is " + para.description());
                    System.out.println("*** The parameter allowed values  is " + para.allowedValues());
                }
            }

        } catch (RdsException e) {
            System.out.println(e.getLocalizedMessage());
            System.exit(1);
        }
    }

class InstanceWrapper:
    """Encapsulates Amazon RDS DB instance actions."""

    def __init__(self, rds_client):
        """
        :param rds_client: A Boto3 Amazon RDS client.
        """
        self.rds_client = rds_client

    @classmethod
    def from_client(cls):
        """
        Instantiates this class from a Boto3 client.
        """
        rds_client = boto3.client("rds")
        return cls(rds_client)


    def get_parameters(self, parameter_group_name, name_prefix="", source=None):
        """
        Gets the parameters that are contained in a DB parameter group.

        :param parameter_group_name: The name of the parameter group to query.
        :param name_prefix: When specified, the retrieved list of parameters is filtered
                            to contain only parameters that start with this prefix.
        :param source: When specified, only parameters from this source are retrieved.
                       For example, a source of 'user' retrieves only parameters that
                       were set by a user.
        :return: The list of requested parameters.
        """
        try:
            kwargs = {"DBParameterGroupName": parameter_group_name}
            if source is not None:
                kwargs["Source"] = source
            parameters = []
            paginator = self.rds_client.get_paginator("describe_db_parameters")
            for page in paginator.paginate(**kwargs):
                parameters += [
                    p
                    for p in page["Parameters"]
                    if p["ParameterName"].startswith(name_prefix)
                ]
        except ClientError as err:
            logger.error(
                "Couldn't get parameters for %s. Here's why: %s: %s",
                parameter_group_name,
                err.response["Error"]["Code"],
                err.response["Error"]["Message"],
            )
            raise
        else:
            return parameters

require "aws-sdk-rds"  # v2: require 'aws-sdk'

# List all Amazon Relational Database Service (Amazon RDS) parameter groups.
#
# @param rds_resource [Aws::RDS::Resource] An SDK for Ruby Amazon RDS resource.
# @return [Array, nil] List of all parameter groups, or nil if error.
def list_parameter_groups(rds_resource)
  parameter_groups = []
  rds_resource.db_parameter_groups.each do |p|
    parameter_groups.append({
                              "name": p.db_parameter_group_name,
                              "description": p.description
                            })
  end
  parameter_groups
rescue Aws::Errors::ServiceError => e
  puts "Couldn't list parameter groups:\n #{e.message}"
end