CREATE TABLE system_metrics (
    host STRING,
    idc STRING,
    cpu_util DOUBLE,
    memory_util DOUBLE,
    disk_util DOUBLE,
    ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    PRIMARY KEY(host, idc),
    TIME INDEX(ts)
);

Affected Rows: 0

INSERT INTO system_metrics
VALUES
    ("host1", "idc_a", 11.8, 10.3, 10.3, 1667446797450),
    ("host2", "idc_a", 80.1, 70.3, 90.0, 1667446797450),
    ("host1", "idc_b", 50.0, 66.7, 40.6, 1667446797450);

Affected Rows: 3

SELECT * FROM system_metrics;

+-------+-------+----------+-------------+-----------+-------------------------+
| host  | idc   | cpu_util | memory_util | disk_util | ts                      |
+-------+-------+----------+-------------+-----------+-------------------------+
| host1 | idc_a | 11.8     | 10.3        | 10.3      | 2022-11-03T03:39:57.450 |
| host1 | idc_b | 50       | 66.7        | 40.6      | 2022-11-03T03:39:57.450 |
| host2 | idc_a | 80.1     | 70.3        | 90        | 2022-11-03T03:39:57.450 |
+-------+-------+----------+-------------+-----------+-------------------------+

SELECT count(*) FROM system_metrics;

+-----------------+
| COUNT(UInt8(1)) |
+-----------------+
| 3               |
+-----------------+

SELECT avg(cpu_util) FROM system_metrics;

+------------------------------+
| AVG(system_metrics.cpu_util) |
+------------------------------+
| 47.29999999999999            |
+------------------------------+

SELECT idc, avg(memory_util) FROM system_metrics GROUP BY idc ORDER BY idc;

+-------+---------------------------------+
| idc   | AVG(system_metrics.memory_util) |
+-------+---------------------------------+
| idc_a | 40.3                            |
| idc_b | 66.7                            |
+-------+---------------------------------+

DROP TABLE system_metrics;

Affected Rows: 1