1.
rsbd1 > select * from master_get_active_worker_nodes();
 node_name | node_port
-----------+-----------
(0 rows)

Wezly robocze nie widza siebie nawzajem, komunikacja jest zarzadzana przez wezel nadzorczy.

2.
SELECT create_distributed_table('measurements', 'me_or_id', colocate_with=>'organizations');

3.
rsbd1=# \d measurements_102082
                     Table "public.measurements_102082"
     Column     |           Type           | Collation | Nullable | Default
----------------+--------------------------+-----------+----------+---------
 me_id          | integer                  |           | not null |
 me_time        | timestamp with time zone |           |          |
 me_temperature | numeric                  |           |          |
 me_lo_id       | integer                  |           |          |
 me_or_id       | integer                  |           | not null |
Indexes:
    "measurements_pkey_102082" PRIMARY KEY, btree (me_or_id, me_id)
Foreign-key constraints:
    "measurements_me_or_id_fkey1_102082" FOREIGN KEY (me_or_id, me_lo_id) REFERENCES loggers_102050(lo_or_id, lo_id)
    "measurements_me_or_id_fkey_102082" FOREIGN KEY (me_or_id) REFERENCES organizations_102018(or_id)

Wedlug dokumentacji Citus nie przeprowadza automatycznie balansowania obciazenia, wiec zapewne wierwsze nie zostaly podzielone po rowno.
4.
Distributed Query into pg_merge_job_0003
   Executor: Real-Time
   Task Count: 32
   Tasks Shown: One of 32
   ->  Task
         Node: host=localhost port=5432 dbname=postgres
         ->  Nested Loop  (cost=0.15..31.13 rows=1 width=232)
               ->  Seq Scan on measurements_102072 measurements  (cost=0.00..22.95 rows=1 width=22)
                     Filter: ((me_time >= '2017-03-15 08:13:00'::timestamp without time zone) AND (me_time <= '2017-03-15 09:18:00'::timestamp without time zo
ne))
               ->  Index Scan using loggers_pkey_102040 on loggers_102040 loggers  (cost=0.15..8.17 rows=1 width=226)
                     Index Cond: ((lo_or_id = measurements.me_or_id) AND (lo_id = measurements.me_lo_id))
 Master Query
   ->  Sort  (cost=0.00..0.00 rows=0 width=0)
         Sort Key: intermediate_column_3_1
         ->  Seq Scan on pg_merge_job_0003  (cost=0.00..0.00 rows=0 width=0)
(15 rows)


32 zadania, gdzie laczny koszt jednego to 62.25

5.
    "me_time_idx_102082" btree (me_time)

6.
Index Scan using me_time_idx_102072 on measurements_102072 measurements  (cost=0.28..8.29 rows=1 width=22)
Koszt spadl z 62.25 do 32.93

7.
Distributed Query
   Executor: Router
   Task Count: 1
   Tasks Shown: All
   ->  Task
         Node: host=localhost port=5432 dbname=postgres
         ->  Nested Loop  (cost=0.43..16.48 rows=1 width=232)
               ->  Index Scan using me_time_idx_102082 on measurements_102082 measurements  (cost=0.29..8.31 rows=1 width=22)
                     Index Cond: ((me_time >= '2017-03-15 08:13:00'::timestamp without time zone) AND (me_time <= '2017-03-15 09:18:00'::timestamp without time zone))

8.
rsbd1=# SELECT * from logger_types_102104;
 lt_id |   lt_name
-------+--------------
     4 | LoggerType4
     2 | LoggerType2
     1 | LoggerType1
     0 | LoggerType0
    -1 | LoggerType-1
    -2 | LoggerType-2
     6 | LoggerType6
(7 rows)

9.
rsbd1=# SELECT * from logger_types_102104;
 lt_id |     lt_name
-------+------------------
     4 | LoggerType4
     1 | LoggerType1
     0 | LoggerType0
    -1 | LoggerType-1
    -2 | LoggerType-2
     6 | LoggerType6
     2 | TypRejestratora2
(7 rows)

10.
Jedna baza danych

 Distributed Query
   Executor: Router
   Task Count: 1
   Tasks Shown: All
   ->  Task
         Node: host=localhost port=5432 dbname=postgres
         ->  Nested Loop  (cost=0.58..24.66 rows=1 width=290)
               ->  Nested Loop  (cost=0.43..16.48 rows=1 width=236)
                     ->  Index Scan using me_time_idx_102082 on measurements_102082 measurements  (cost=0.29..8.31 rows=1 width=22)
                           Index Cond: ((me_time >= '2017-03-15 08:13:00'::timestamp without time zone) AND (me_time <= '2017-03-15 09:18:00'::timestamp witho
ut time zone))
11.
mkdir -p /var/lib/pgsql/rsbd3
initdb /var/lib/pgsql/rsbd3
vim /var/lib/pgsql/rsbd3/postgres.conf
pg_ctl -D rsbd3 -l logfile_rsbd3 start


12.
rsbd3=# \dt
                List of relations
 Schema |        Name         | Type  |  Owner
--------+---------------------+-------+----------
 public | logger_types_102104 | table | postgres
(1 row)


                                                                                                                                            124,1         Bot