Creating a SQL Throttling Rule

Function

This API is used to create a SQL throttling rule. Currently, this function is supported only for MySQL databases. The restrictions are as follows:

Keywords are separated by a tilde (~), for example, select~a. A throttling rule will be applied to SQL statements containing keywords select and a.
If a SQL statement matches multiple rules, only the latest rule is applied.
Keywords of a throttling rule are sorted in a specific order, and the system will match them from first to last. For example, if one rule contains the keyword a~and~b, the system only matches xxx a>1 and b>2.
Generated keywords may be case-sensitive. Execute show variables like 'rds_sqlfilter_case_sensitive' or go to the console to check parameter settings for specifying case-sensitivity.
Throttling rules can only be added for primary instances.
System catalogs are not restricted, queries which do not involve data are not restricted, and the root user is not restricted in specific versions.

URI

POST /v3/{project_id}/instances/{instance_id}/sql-limit/rules

**Table 1** URI parameters
Parameter	Mandatory	Type	Description
project_id	Yes	String	Explanation: Project ID of a tenant in a region To obtain this value, see Obtaining a Project ID. Constraints: N/A Values: The value can contain 32 characters. Only letters and digits are allowed. Default value: N/A
instance_id	Yes	String	Explanation: Unique ID of an instance Constraints: N/A Values: The value can contain 32 characters. Only letters and digits are allowed. Default value: N/A

Request Parameters

**Table 2** Request body parameters
Parameter	Mandatory	Type	Description
datastore_type	Yes	String	Explanation: Database type Constraints: N/A Values: MySQL Default value: N/A
sql_limit_rules	Yes	Array of CreateSqlLimitRuleOption objects	Explanation: SQL throttling rules to be created. A maximum of 5 rules can be created at a time. Constraints: N/A Values: N/A Default value: N/A
database_name	No	String	Explanation: Database name Constraints: Only MySQL databases are supported. Values: N/A Default value: N/A

**Table 3** CreateSqlLimitRuleOption
Parameter	Mandatory	Type	Description
sql_type	Yes	String	Explanation: SQL type Constraints: N/A Values: SELECT UPDATE DELETE Default value: N/A
max_concurrency	Yes	Integer	Explanation: Maximum concurrent SQL statements Constraints: N/A Values: [0, 2^31-1]. The actual value depends on the query result. Default value: N/A
pattern	Yes	String	Explanation: SQL throttling rule Constraints: Keywords are separated by a tilde (~), for example, select~a. The throttling rule will be applied to SQL statements containing keywords select and a. Values: N/A Default value: N/A
max_waiting	No	Integer	Explanation: Maximum waiting time Constraints: N/A Values: [0, 2^31-1]. The actual value depends on the query result. Default value: N/A
his_sql_limit_switch	No	Boolean	Explanation: Whether historical SQL throttling rules are enabled Constraints: This parameter takes effect only for the current SQL throttling rule. When this parameter is set to ON, existing sessions that match the SQL throttling rule will be killed. Values: true false Default value: N/A

Response Parameters

Status code: 200

None

Example Request

Creating a SQL throttling rule

POST https://das.cn-north-1.myhuaweicloud.com/v3/054c630ff780d4cc2f40c00d7f6fb21d/instances/d871e13ee1044e21a473330cd67047cbin01/sql-limit/rules

{
  "sql_limit_rules" : [ {
    "sql_type" : "SELECT",
    "pattern" : "select~t2~var",
    "max_concurrency" : 100
  }, {
    "sql_type" : "DELETE",
    "pattern" : "delete~t1~name",
    "max_concurrency" : 1
  } ],
  "datastore_type" : "MySQL"
}