Help Center/ Distributed Database Middleware/ API Reference (Kuala Lumpur Region)/ DDM Instance Management/ Querying Parameters of a Specified DDM Instance

Updated on 2022-08-17 GMT+08:00

View PDF

Querying Parameters of a Specified DDM Instance

Function

This API is used to query parameters of a specified DDM instance.

Constraints

None

URI

GET /v3/{project_id}/instances/{instance_id}/configurations

**Table 1** Path parameters
Parameter	Mandatory	Type	Description
project_id	Yes	String	Project ID of a tenant in a region
instance_id	Yes	String	DDM instance ID

Request Parameters

**Table 2** Request header parameters
Parameter	Mandatory	Type	Description
X-Language	No	String	Language. The value can be zh-cn or en-us. The default value is zh-cn.
X-Auth-Token	Yes	String	User token It can be obtained by calling the IAM API (value of X-Subject-Token in the response header).

Response Parameters

Status code: 200

**Table 3** Response body parameters
Parameter	Type	Description
updated	String	Time when the instance parameter is last updated
configuration_parameter	Array of ConfigurationParameterList objects	Information about DDM instance parameters

**Table 4** ConfigurationParameterList
Parameter	Type	Description
name	String	Parameter name
value	String	Parameter value
need_restart	String	Whether the DDM instance needs to be restarted
read_only	String	Whether the parameter is read-only
value_range	String	Parameter value range
data_type	String	Data type of the parameter
description	String	Parameter description

Status code: 400

**Table 5** Response body parameters
Parameter	Type	Description
errCode	String	Service error code
externalMessage	String	Error message

Status code: 500

**Table 6** Response body parameters
Parameter	Type	Description
errCode	String	Service error code
externalMessage	String	Error message

Example Request

GET https://{endpoint}/v3/{project_id}/instances/{instance_id}/configurations

Example Response

Status code: 200

{
    "updated": "2021-04-08 07:10:43",
    "configuration_parameter": [
        {
            "name": "bind_table",
            "value": "",
            "need_restart": "0",
            "readonly": "0",
            "value_range": null,
            "datatype": "string",
            "description": 'Data association among multiple sharded tables. Based on the association, the optimizer processes JOIN operations at the MySQL layer. The format is: [{tb.col1,tb2.col2},{tb.col2,tb3.col1},...]'
        },
        {
            "name": "character_set_server",
            "value": "gbk",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "gbk|utf8|utf8mb4",
            "datatype": "string",
            "description": DDM server's character set. To store emoticons, set both this parameter and the character set on RDS to utf8mb4.
        },
        {
            "name": "collation_server",
            "value": "gbk_bin",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "utf8_unicode_ci|utf8_bin|gbk_chinese_ci|gbk_bin|utf8mb4_unicode_ci|utf8mb4_bin",
            "datatype": "string",
            "description": "DDM server's collation."
        },
        {
            "name": "concurrent_execution_level",
            "value": "DATA_NODE",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "RDS_INSTANCE|DATA_NODE|PHY_TABLE",
            "datatype": "string",
            "description": "Concurrency level of scanning table shards in a logical table: DATA_NODE: indicates that database shards are scanned in parallel and table shards in each database shard are scanned in serial. RDS_INSTANCE: indicates that RDS DB instances are scanned in parallel and shards in each DB instance are scanned in serial. PHY_TABLE: indicates that all table shards are scanned in parallel."
        },
        {
            "name": "connection_idle_timeout",
            "value": "28801",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "60-86400",
            "datatype": "integer",
            "description": "Number of seconds that the server waits for activity on a connection before closing it. The default value is 28800, indicating that the server waits for 28800 seconds before closing the connection."
        },
        {
            "name": "enable_table_recycle",
            "value": "OFF",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "OFF|ON",
            "datatype": "boolean",
            "description": "Whether the table recycle bin is enabled."
        },
        {
            "name": "insert_to_load_data",
            "value": "OFF",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "OFF|ON",
            "datatype": "boolean",
            "description": "Whether the constant values are inserted by executing the LOAD DATA statement."
        },
        {
            "name": "live_transaction_timeout_on_shutdown",
            "value": "1",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "0-100",
            "datatype": "integer",
            "description": "Timeout limit of an in-transit transaction, in seconds. The default value is 1, indicating that the server waits for 1 second before closing the connection."
        },
        {
            "name": "long_query_time",
            "value": "1",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "0.01-10",
            "datatype": "float",
            "description": "Minimum duration of a query to be logged as slow, in seconds. The default value is 1, indicating that the query is considered as a slow query if its execution duration is greater than or equal to 1 second."
        },
        {
            "name": "max_allowed_packet",
            "value": "16777216",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "1024-1073741824",
            "datatype": "integer",
          "description":"Maximum size of a packet or any generated intermediate string. The packet message buffer is initialized to net_buffer_length bytes, but can grow up to max_allowed_packet bytes if required. By default, this parameter is set to a small value to detect large (and possibly incorrect) packets. The value should be a multiple of 1024. The default value is 16777216."
        },
        {
            "name": "max_backend_connections",
            "value": "0",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "0-10000000",
            "datatype": "integer",
            "description": "Maximum concurrent connections from a DDM node to an RDS DB instance. When this parameter is set to 0 (default), the maximum concurrent connections from a DDM node to an RDS DB instance is: (RDS DB instance's maximum connections - 20)/Number of DDM nodes."
        },
        {
            "name": "max_connections",
            "value": "20000",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "10-40000",
            "datatype": "integer",
            "description": "Maximum number of concurrent connections allowed per DDM instance. The value is related to the class and number of associated RDS DB instances. The default value is 20000, indicating that the maximum number of concurrent connections cannot exceed 40000."
        },
        {
            "name": "min_backend_connections",
            "value": "10",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "0-10000000",
            "datatype": "integer",
            "description": "Minimum concurrent connections from a DDM node to an RDS DB instance. The default value is 10."
        },
        {
            "name": "not_from_pushdown",
            "value": "OFF",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "OFF|ON",
            "datatype": "boolean",
            "description": "Whether the SELECT statements that do not contain any FROM clauses are pushed down."
        },
        {
            "name": "seconds_behind_master",
            "value": "30",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "0-7200",
            "datatype": "integer",
            "description": "Threshold in seconds of the replication lag between a primary RDS DB instance to its read replica. The default value is 30, indicating that the time for data replication between the primary RDS DB instance and its read replica cannot exceed 30 seconds. If the time exceeds 30 seconds, the data read requests are no longer forwarded to the read replica.
        },
        {
            "name": "sql_audit",
            "value": "OFF",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "OFF|ON",
            "datatype": "boolean",
            "description": "Whether SQL audit is enabled."
        },
        {
            "name": "sql_execute_timeout",
            "value": "28800",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "100-28800",
            "datatype": "integer",
            "description": "Number of seconds to wait for a SQL statement to execute before it times out. The default value is 28800, indicating that the SQL statement times out if its execution time is greater than or equal to 28800 seconds."
        },
        {
            "name": "support_ddl_binlog_hint",
            "value": "OFF",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "OFF|ON",
            "datatype": "boolean",
            "description": " Whether a binlog hint is added to each DDL statement."
        },
        {
            "name": "transaction_policy",
            "value": "XA",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "XA|FREE|NO_DTX",
            "datatype": "string",
            "description": "Transactions supported by DDM: * XA transaction, which attempts to ensure atomicity and isolation. * FREE transaction, which is a best-effort commit transaction that allows data to be written to multiple shards, without impacting performance. FREE transactions do not ensure atomicity. * NO_DTX transaction, which is a single-shard transaction."
        },
        {
            "name": "ultimate_optimize",
            "value": "ON",
            "need_restart": "0",
            "readonly": "0",
            "value_range": "OFF|ON",
            "datatype": "boolean",
            "description": "Optimize the SQL execution plan based on parameter values."
        }
    ]
}

Status code: 400

bad request

{
  "externalMessage" : "Parameter error.",
  "errCode" : "DBS.280001"
}

Status code: 500

server error

{
  "externalMessage" : "Parameter error.",
  "errCode" : "DBS.280001"
}

Status Codes

Status Code	Description
200	OK
400	bad request
500	server error

Error Codes

For details, see Error Codes.

Parent topic: DDM Instance Management

Previous topic: Querying Details of a DDM Instance Node

Next topic: Modifying Parameters of a DDM Instance

Feedback

Was this page helpful?

Helpful Not helpful

Provide feedback

Thank you very much for your feedback. We will continue working to improve the documentation.See the reply and handling status in My Cloud VOC.

The system is busy. Please try again later.

Which of the following issues have you encountered?

Content is inconsistent with the product UI

Unclear descriptions

Lack of examples or code

Incorrect steps

Can't find what I need

Lack of best practices

Feedback (optional)

0/500

Select at least one type of issue, and enter your comments or suggestions.

Enter a maximum of 500 characters.

Submit Cancel

For any further questions, feel free to contact us through the chatbot.

Chatbot