利用高级监控仪表板解决常见数据库问题

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<clickhouse>
    <metric_log>
        <database>system</database>
        <table>metric_log</table>
        <flush_interval_milliseconds>7500</flush_interval_milliseconds>
        <collect_interval_milliseconds>1000</collect_interval_milliseconds>
        <max_size_rows>1048576</max_size_rows>
        <reserved_size_rows>8192</reserved_size_rows>
        <buffer_size_rows_flush_threshold>524288</buffer_size_rows_flush_threshold>
        <flush_on_crash>false</flush_on_crash>
    </metric_log>
    <asynchronous_metric_log>
        <database>system</database>
        <table>asynchronous_metric_log</table>
        <flush_interval_milliseconds>7500</flush_interval_milliseconds>
        <collect_interval_milliseconds>1000</collect_interval_milliseconds>
        <max_size_rows>1048576</max_size_rows>
        <reserved_size_rows>8192</reserved_size_rows>
        <buffer_size_rows_flush_threshold>524288</buffer_size_rows_flush_threshold>
        <flush_on_crash>false</flush_on_crash>
    </asynchronous_metric_log>
</clickhouse>

-- Create dashboard user
CREATE USER dashboard_user IDENTIFIED BY ;


-- Grant rights to access advanced dashboards
GRANT REMOTE ON *.* to dashboard;
GRANT CREATE TEMPORARY TABLE on *.* to dashboard;
GRANT SELECT ON system.metric_log to dashboard;
GRANT SELECT ON system.asynchronous_metric_log to dashboard;
GRANT SELECT ON system.dashboards to dashboard;

-- Load dashboard definition
SELECT title, query FROM system.dashboards WHERE dashboard = 'Overview'

SELECT toStartOfInterval(event_time, INTERVAL {rounding:UInt32} SECOND)::INT AS t, avg(value) FROM merge('system', '^asynchronous_metric_log') WHERE event_date >= toDate(now() - {seconds:UInt32}) AND event_time >= now() - {seconds:UInt32} AND metric = 'TotalPrimaryKeyBytesInMemory' GROUP BY t ORDER BY t WITH FILL STEP {rounding:UInt32}

-- Create a separate database
CREATE DATABASE custom;


-- Create the custom dashboard table
CREATE TABLE custom.dashboards
(
    `dashboard` String,
    `title` String,
    `query` String
) ORDER BY ()

-- Total size primary keys visualization query
INSERT INTO custom.dashboards (dashboard, title, query)
VALUES (
    'Overview',
    'Total primary keys size',
    'SELECT toStartOfInterval(event_time, INTERVAL {rounding:UInt32} SECOND)::INT AS t, avg(value) FROM merge(\'system\', \'^asynchronous_metric_log\') WHERE event_date >= toDate(now() - {seconds:UInt32}) AND event_time >= now() - {seconds:UInt32} AND metric = \'TotalPrimaryKeyBytesInMemory\' GROUP BY t  ORDER BY t WITH FILL STEP  {rounding:UInt32}'
);

SELECT title, query FROM merge(REGEXP('custom|system'),'dashboards') WHERE dashboard = 'Overview'

SELECT
    type,
    event_time,
    query_duration_ms,
    query,
    read_rows,
    tables
FROM system.query_log
WHERE has(databases, 'default') AND (event_time >= '2024-12-23 11:20:00') AND (event_time <= '2024-12-23 11:30:00') AND (type = 'QueryFinish')
ORDER BY query_duration_ms DESC
LIMIT 5
FORMAT VERTICAL


Row 1:
──────
type:              QueryFinish
event_time:        2024-12-23 11:22:55
query_duration_ms: 37407
query:             SELECT
    toStartOfMonth(review_date) AS month,
    any(product_title),
    avg(star_rating) AS avg_stars
FROM amazon_reviews_no_pk
WHERE
    product_category = 'Home'
GROUP BY
    month,
    product_id
ORDER BY
    month DESC,
    product_id ASC
LIMIT 20
read_rows:         150957260
tables:            ['default.amazon_reviews_no_pk']


Row 2:
──────
type:              QueryFinish
event_time:        2024-12-23 11:26:50
query_duration_ms: 7325
query:             SELECT
    toStartOfMonth(review_date) AS month,
    any(product_title),
    avg(star_rating) AS avg_stars
FROM amazon_reviews_no_pk
WHERE
    product_category = 'Home'
GROUP BY
    month,
    product_id
ORDER BY
    month DESC,
    product_id ASC
LIMIT 20
read_rows:         150957260
tables:            ['default.amazon_reviews_no_pk']


Row 3:
──────
type:              QueryFinish
event_time:        2024-12-23 11:24:10
query_duration_ms: 3270
query:             SELECT
    toStartOfMonth(review_date) AS month,
    any(product_title),
    avg(star_rating) AS avg_stars
FROM amazon_reviews_pk
WHERE
    product_category = 'Home'
GROUP BY
    month,
    product_id
ORDER BY
    month DESC,
    product_id ASC
LIMIT 20
read_rows:         6242304
tables:            ['default.amazon_reviews_pk']


Row 4:
──────
type:              QueryFinish
event_time:        2024-12-23 11:28:10
query_duration_ms: 2786
query:             SELECT
    toStartOfMonth(review_date) AS month,
    any(product_title),
    avg(star_rating) AS avg_stars
FROM amazon_reviews_pk
WHERE
    product_category = 'Home'
GROUP BY
    month,
    product_id
ORDER BY
    month DESC,
    product_id ASC
LIMIT 20
read_rows:         6242304
tables:            ['default.amazon_reviews_pk']