System administration functions

This page lists both RisingWave system administration functions and PostgreSQL system administration functions that are supported in RisingWave.

current_setting()

Returns the current value of a specified runtime parameter. This function corresponds to the SQL command SHOW.

Example

SELECT current_setting ('server_version');
---------RESULT
 current_setting 
-----------------
 8.3.0
(1 row)

You can use the SHOW ALL command to get the complete list of runtime parameters and corresponding descriptions.

set_config()

Syntax

set_config ( setting_name text, new_value text, is_local boolean ) → text

Sets the parameter setting_name to new_value, and returns that value. If is_local is true, the new value will only apply during the current transaction. If you want the new value to apply for the rest of the current session, use false instead. This function corresponds to the SQL command SET.

Example

SELECT set_config('rw_implicit_flush', 'true', false);
-------
true

pg_indexes_size('table_name')

Returns the total size of all indexes associated with a particular table in bytes.

Example

SELECT pg_indexes_size('t1');
---------RESULT
 pg_indexes_size 
-----------------
               0
(1 row)

pg_table_size('table_name')

Returns the size of a table in bytes.

Example

SELECT pg_table_size('t1');
---------RESULT
 pg_table_size 
---------------
           240
(1 row)

pg_stat_get_numscans('table_name')

Returns the total number of scans (sequential and index scans) performed on a specified table since the server was started.

Example

SELECT pg_stat_get_numscans('my_table');
 pg_stat_get_numscans 
----------------------
                    0
(1 row)

note

This is a dummy function intended for compatibility with third-party tools. We keep it here only for reference and it will be eventually removed. Please do not use it in production environments or any important tasks.