runtime_filter_max_in_num

Description

The runtime_filter_max_in_num variable specifies the maximum number of distinct values (NDV) in a column for which the runtime in filter is used.

Privilege requirements

• Query variables

  • Global level

    Users in the sys tenant and all user tenants can execute the SHOW VARIABLES statement or view SYS.TENANT_VIRTUAL_GLOBAL_VARIABLE (Oracle mode) or information_schema.GLOBAL_VARIABLES (MySQL mode) to query the value of a global system variable.

  • Session level

    Users in the sys tenant and all user tenants can execute the SHOW VARIABLES statement or view SYS.TENANT_VIRTUAL_SESSION_VARIABLE (Oracle mode) or information_schema.SESSION_VARIABLES (MySQL mode) to query the value of a session system variable.

• Modify variables

  • Set the variable at the global level

    • Users in the sys tenant can directly modify the value of a global system variable.

    • MySQL users in a user tenant must have the SUPER or ALTER SYSTEM privilege to modify the value of a global system variable.

    • Oracle users in a user tenant of V4.x must have the ALTER SYSTEM privilege to modify the value of a global system variable, starting from V4.2.0.

  • Set the variable at the session level

    Users in the sys tenant and all user tenants can directly modify the value of a session system variable in their own tenant.

Attributes

Sample configurations

set runtime_filter_wait_time_ms = 100;

set global runtime_filter_max_in_num = 512;