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Signed-off-by: xxchan <xxchan22f@gmail.com>

operate/view-configure-runtime-parameters.mdx

@@ -4,7 +4,7 @@ title: "View and configure runtime parameters"
 
 ## What are runtime parameters?
 
-Runtime parameters are variables that can be set at runtime to configure the behavior of RisingWave.
+Runtime parameters are variables that can be set at runtime to configure the behavior of RisingWave. They are also known as session variables.
 
 ## How to view runtime parameters?
 
@@ -94,6 +94,10 @@ Where `parameter_name` is the name of the parameter, and `value` or `'value'` is
 
 For details about the `set_config()` function, see [System administration functions](/sql/functions/sys-admin#set-config), and for details about the `SET` command, see [SET](/sql/commands/sql-set).
 
+<Note>
+`SET` only takes effect in the current session.
+</Note>
+
 You can also use the [ALTER SYSTEM SET](/sql/commands/sql-alter-system) command to set a system-wide default value for a runtime parameter. This configuration will then be applied to every new session.
 
 <Note>