Resize cluster 3 => 1, unused buddies

I think you'll need to drop the b1 projections yourself, but it's really easy to automate the drops..

Example:

dbadmin=> SELECT current_fault_tolerance FROM system;
 current_fault_tolerance
-------------------------
                       1
(1 row)

dbadmin=> SELECT COUNT(*) FROM nodes;
 COUNT
-------
     3
(1 row)

dbadmin=> CREATE TABLE test (c1 INT) SEGMENTED BY HASH(c1) ALL NODES;
CREATE TABLE

dbadmin=> INSERT /*+ DIRECT */ INTO test SELECT RANDOMINT(10000) FROM vs_columns;
 OUTPUT
--------
   9319
(1 row)

dbadmin=> COMMIT;
COMMIT

dbadmin=> SELECT node_name, projection_name, row_count FROM projection_storage ORDER BY 1, 2;
        node_name         | projection_name | row_count
--------------------------+-----------------+-----------
 v_test_k1_to_k0_node0001 | test_b0         |      3106
 v_test_k1_to_k0_node0001 | test_b1         |      3111
 v_test_k1_to_k0_node0002 | test_b0         |      3102
 v_test_k1_to_k0_node0002 | test_b1         |      3106
 v_test_k1_to_k0_node0003 | test_b0         |      3111
 v_test_k1_to_k0_node0003 | test_b1         |      3102
(6 rows)

dbadmin=> SELECT MARK_DESIGN_KSAFE(0);
WARNING 6022:  Setting K-safety to 0 could result in catastrophic data loss in the event of a failure.  Do not use k=0 in a production environment. For test, dev or other non-production environments, K=0 may be acceptable however Vertica still recommends a minimum value of K=1
  MARK_DESIGN_KSAFE
----------------------
 Marked design 0-safe
(1 row)

dbadmin=> \q

[dbadmin@vertica01 ~]$ admintools -t list_allnodes
 Node                     | Host          | State | Version         | DB
--------------------------+---------------+-------+-----------------+---------------
 v_test_k1_to_k0_node0001 | 192.168.2.200 | UP    | vertica-9.1.1.4 | test_k1_to_k0
 v_test_k1_to_k0_node0002 | 192.168.2.201 | UP    | vertica-9.1.1.4 | test_k1_to_k0
 v_test_k1_to_k0_node0003 | 192.168.2.202 | UP    | vertica-9.1.1.4 | test_k1_to_k0

[dbadmin@vertica01 ~]$ admintools -t db_remove_node -d test_k1_to_k0 -s v_test_k1_to_k0_node0002,v_test_k1_to_k0_node0003
connecting to 192.168.2.200

Starting Data Rebalancing tasks.  Please wait....
This process could take a long time; allow it to complete uninterrupted.
Use Ctrl+C if you must cancel the session.

        Data Rebalance completed successfully.
Attempting to drop node v_test_k1_to_k0_node0002 ( 192.168.2.201 )
        Shutting down node v_test_k1_to_k0_node0002
        Sending node shutdown command to '['v_test_k1_to_k0_node0002', '192.168.2.201', '/home/dbadmin', '/home/dbadmin']'
        Deleting catalog and data directories
        Update admintools metadata for v_test_k1_to_k0_node0002
Attempting to drop node v_test_k1_to_k0_node0003 ( 192.168.2.202 )
        Shutting down node v_test_k1_to_k0_node0003
        Sending node shutdown command to '['v_test_k1_to_k0_node0003', '192.168.2.202', '/home/dbadmin', '/home/dbadmin']'
        Deleting catalog and data directories
        Update admintools metadata for v_test_k1_to_k0_node0003
        Reload spread configuration
        Replicating configuration to all nodes
        Checking database state
        Node Status: v_test_k1_to_k0_node0001: (UP)

[dbadmin@vertica01 ~]$ vsql -c "SELECT node_name, projection_name, row_count FROM projection_storage ORDER BY 1, 2;"
        node_name         | projection_name | row_count
--------------------------+-----------------+-----------
 v_test_k1_to_k0_node0001 | test_b0         |      9319
 v_test_k1_to_k0_node0001 | test_b1         |      9319
(2 rows)

[dbadmin@vertica01 ~]$ vsql -Atc "SELECT 'DROP PROJECTION ' || projection_schema || '.' || projection_name || ' CASCADE;' FROM projections WHERE is_segmented LIMIT 1 OVER(PARTITION BY anchor_table_id ORDER BY projection_schema, projection_name DESC);" | vsql
DROP PROJECTION

[dbadmin@vertica01 ~]$ vsql -c "SELECT node_name, projection_name, row_count FROM projection_storage ORDER BY 1, 2;"                                                                                                                                 node_name         | projection_name | row_count
--------------------------+-----------------+-----------
 v_test_k1_to_k0_node0001 | test_b0         |      9319
(1 row)

Be careful! First run this command and make sure the DROP commands are for the projections you want to DROP!

vsql -Atc "SELECT 'DROP PROJECTION ' || projection_schema || '.' || projection_name || ' CASCADE;' FROM projections WHERE is_segmented LIMIT 1 OVER(PARTITION BY anchor_table_id ORDER BY projection_schema, projection_name DESC);"

In the example above the output from that command are a series of DROP PROJECTION commands that are piped through vsql where they'll run.