How to find the projections that are not used by the query optimizer from long time?

Hi,

There is a table that has the list of projection used.

dbadmin=> \d v_monitor.projection_usage
                                                  List of Fields by Tables
  Schema   |      Table       |        Column         |     Type     | Size | Default | Not Null | Primary Key | Foreign Key
-----------+------------------+-----------------------+--------------+------+---------+----------+-------------+-------------
 v_monitor | projection_usage | anchor_table_id       | int          |    8 |         | f        | f           |
 v_monitor | projection_usage | anchor_table_name     | varchar(128) |  128 |         | f        | f           |
 v_monitor | projection_usage | anchor_table_schema   | varchar(128) |  128 |         | f        | f           |
 v_monitor | projection_usage | io_type               | varchar(128) |  128 |         | f        | f           |
 v_monitor | projection_usage | node_name             | varchar(128) |  128 |         | f        | f           |
 v_monitor | projection_usage | projection_id         | int          |    8 |         | f        | f           |
 v_monitor | projection_usage | projection_name       | varchar(128) |  128 |         | f        | f           |
 v_monitor | projection_usage | query_start_timestamp | timestamptz  |    8 |         | f        | f           |
 v_monitor | projection_usage | request_id            | int          |    8 |         | f        | f           |
 v_monitor | projection_usage | session_id            | varchar(128) |  128 |         | f        | f           |
 v_monitor | projection_usage | statement_id          | int          |    8 |         | f        | f           |
 v_monitor | projection_usage | transaction_id        | int          |    8 |         | f        | f           |
 v_monitor |

you could do a left join with the projection tables and see the one that had not been used.

will this help?

Eugenia