@Rocky when we have VARIABLES they also like ADMIN SET CONFIGS? so we should also add that variables into fe config to be persistent after restart?

In StarRocks, System Variables and FE Configurations (ADMIN SET CONFIG) behave differently regarding persistence: 1. FE Configurations (

ADMIN SET FRONTEND CONFIG

) These are not persistent across restarts. * Behavior: When you use

ADMIN SET FRONTEND CONFIG ("key" = "value")

, the change is applied to the running FE process immediately. However, if the FE restarts, it reloads its configuration from the

fe.conf

file. * Action Required: To make these changes permanent, you must manually add the configuration item into your

fe.conf

file. 2. System Variables (

SET GLOBAL ...

) These are persistent across restarts. * Behavior: System variables (such as

query_mem_limit

,

wait_timeout

, etc.) are stored in the FE's internal metadata (the BDBJE catalog). When you run

SET GLOBAL <var_name> = <value>

, the change is written to the metadata and will automatically be reloaded even if the cluster or FE is restarted. * Action Required: You do not need to add these to

fe.conf

. In fact,

fe.conf

does not support system variables; it is only for FE engine parameters (like ports, JVM settings, and cluster management configs). Summary Comparison Feature | Command | Persists after restart? | Action for persistence FE Configs |

ADMIN SET FRONTEND CONFIG

| No | Add to

fe.conf

Global Variables |

SET GLOBAL <var>

| Yes | None (saved in metadata) Session Variables |

SET <var>

| No | Valid only for the current connection Note: If you want a global variable to take effect for the current session as well, remember that

SET GLOBAL

only affects future connections. You usually need to run both:

sql
SET query_mem_limit = 137438953472;        -- Current session
SET GLOBAL query_mem_limit = 137438953472; -- Future sessions (persistent)

References • quick_start/helm.md • administration/Meta_recovery.md • sql-reference/System_variable.md