In the DRDS console, you can view instance and database parameters and modify parameter values as needed.

Note

  • If your instance is read-only, you can set only Database parameters, and cannot set Instance parameters.
  • Some parameters are only supported for instances of specific versions. For more information, see Parameter description.

Parameter description

Level Parameter Description Supported version
Instance SLOW_SQL_TIME The threshold for slow SQL queries. SQL queries that exceed this threshold are recorded in slow logical SQL logs. 5.3.4-15378085 or later. .
LOGIC_IDLE_TIMEOUT The timeout period for an idle connection between the client and the DRDS instance. Unit: milliseconds. 5.3.4-15378085 or later. .
MAX_ALLOWED_PACKET The maximum size of a packet between the client and the DRDS instance. Unit: bytes. 5.3.4-15378085 or later. .
Database MAX_POOL_SIZE The maximum number of connections between a DRDS database and a single ApsaraDB for RDS database shard. All versions.
MIN_POOL_SIZE The minimum number of connections between a DRDS database and a single ApsaraDB for RDS database shard. All versions.
IDLE_TIMEOUT The timeout period for an idle connection between a DRDS database and an ApsaraDB for RDS database shard. All versions.
SOCKET_TIMEOUT The timeout period for an SQL query sent from DRDS database to an ApsaraDB for RDS database. All versions.
FORBID_EXECUTE_DML_ALL Specifies whether to prohibit full table deletion and update. All versions.
TEMP_TABLE_MAX_ROWS The size of an intermediate temporary table used during distributed queries in DRDS. 5.3.4-15378085 or later. .
MERGE_UNION_SIZE The maximum number of table shards that can be combined by executing the UNION statement when you query multiple table shards in a database. 5.3.4-15378085 or later. .
PURE_ASYNC_DDL_MODE Specifies whether to enable the pure asynchronous-mode when the asynchronous data definition language (DDL) engine is enabled.
  • When this mode is enabled, the client connects to the DRDS instance and immediately returns when a DDL statement is executed. You can use DDL management statements to view the execution status.
  • If this mode is disabled, the synchronous mode remains. The client does not return until the execution of a DDL statement is completed.
5.3.4-15378085 or later. .
ENABLE_RANDOM_PHY_TABLE_NAME Specifies whether a random name is used for a physical table. 5.3.4-15378085 or later. .

Procedure

  1. Log on to the DRDS console.
  2. In the top navigation bar, select the region where the target instance is located.
  3. In the left-side navigation pane, click Instances.
  4. Find the target instance and click its ID.
  5. In the left-side navigation pane, choose Diagnostics and Optimization > Parameter Settings. Then, you can click the Instance or Database tab to modify the values of corresponding parameters.
    • Modify the values of Instance parameters
      1. On the Instance tab, find the target parameter, and click Icon in the Parameter Value column.Modify the value of instance parameter 1
        Note You can click Parameter icon in the Description column to view the description of the target parameter.
      2. In the dialog box that appears, enter a value and click OK.Edit
        Note The value you entered must be in the Editable Value range. If the value is out of the range, when you click Submit, an error message appears.
    • Modify the values of Database parameters
      1. Click the Database tab, find the target database, and then click the target database tab.Database
      2. Find the target parameter, and click Icon in the Parameter Value column.Modify the values of database parameters
        Note You can click Parameter icon in the Description column to view the description of the target parameter.
      3. In the dialog box that appears, enter a value and click OK.Modify the values of database parameters
        Note The value you entered must be in the Editable Value range. If the value is out of the range, when you click Submit, an error message appears.
  6. After you modify a Parameter Value, click Submit.
    Submit
    Note For parameters whose Restart column is Yes, after you click Submit to submit new values of Parameter Value, you must restart the instance to make the new values take effect.