Viewing Current Data Retention Policy

To view the current retention policy for a Data Collector component, use the GET_DATA_COLLECTOR_POLICY() function and supply the component name as the function's argument.

To retrieve a list of all current component names, query the V_MONITOR.DATA_COLLECTOR system table, which returns Data Collector components, their current retention policies, and statistics about how much data is retained. For example:

mcdb=> \xExpanded display is on.
mcdb=> SELECT * from data_collector;
-[ RECORD 1 ]----------+-------------------------------------------------------------------------------------------
node_name              | v_mcdb_node0001
component              | AllocationPoolStatistics
table_name             | dc_allocation_pool_statistics
description            | Information about global memory pools, which generally cannot be recovered without restart
access_restricted      | t
in_db_log              | f
in_vertica_log         | f
memory_buffer_size_kb  | 64
disk_size_kb           | 256
record_too_big_errors  | 0
lost_buffers           | 0
lost_records           | 0
retired_files          | 1429
retired_records        | 647358
current_memory_records | 0
current_disk_records   | 1493
current_memory_bytes   | 0
current_disk_bytes     | 215737
first_time             | 2012-11-30 07:04:30.000726-05
last_time              | 2012-11-30 07:16:56.000631-05
kb_per_day             | 24377.3198211312
-[ RECORD 2 ]----------+-------------------------------------------------------------------------------------------

The following command returns the retention policy for a specific component, NodeState.

=> SELECT get_data_collector_policy('NodeState');

The results let you know that 10KB is retained in memory and 100KB on disk:

        get_data_collector_policy------------------------------------------
 10KB kept in memory, 100KB kept on disk.
(1 row)