版本：1.2

Trigger

Trigger 允许用户基于 SQL 语句定义触发规则，GreptimeDB 根据这些触发规则进行周期性计算，当满足条件后对外发出通知。

关键特性

SQL 原生：用 SQL 定义触发规则，复用 GreptimeDB 内置函数，无需额外学习成本
多阶段状态管理：内置 pending / firing / inactive 状态机，防止抖动和重复通知
丰富的上下文：自定义 labels 和 annotations，并自动注入查询结果字段，便于精准定位根因
生态友好：告警负载完全兼容 Prometheus Alertmanager，可直接使用其分组、抑制、静默和路由功能

快速入门示例

本节通过端到端示例展示如何监控系统负载（load1），当负载超过阈值时触发告警。

在本示例中你将：

创建指标表：建立 load1 表存储主机负载指标
定义 Trigger：通过 SQL 设定触发条件，配置 labels、annotations 及通知方式
模拟数据写入：依次注入正常与异常的负载数据，激活告警逻辑
观察状态变化：实时查看告警实例从 pending → firing → inactive 的完整生命周期

1. 创建数据表

使用 MySQL 客户端连接 GreptimeDB，并创建 load1 表：

CREATE TABLE `load1` (
    host            STRING,
    load1           FLOAT32,
    ts              TIMESTAMP TIME INDEX
) WITH ('append_mode'='true');

2. 创建 Trigger

使用 MySQL 客户端连接 GreptimeDB，并创建 load1_monitor Trigger：

CREATE TRIGGER IF NOT EXISTS `load1_monitor`
    ON (
        SELECT
            host          AS label_host,
            avg(load1)    AS avg_load1,
            max(ts)       AS ts
        FROM public.load1
        WHERE ts >= NOW() - '1 minutes'::INTERVAL
        GROUP BY host
        HAVING avg(load1) > 10
    ) EVERY '1 minutes'::INTERVAL
    FOR '3 minutes'::INTERVAL
    KEEP FIRING FOR '3 minutes'::INTERVAL
    LABELS (severity=warning)
    ANNOTATIONS (comment='Your computer is smoking, should take a break.')
    NOTIFY(
        WEBHOOK alert_manager URL 'http://localhost:9093' WITH (timeout='1m')
    );

该 Trigger 每分钟运行一次，计算过去 60 秒内每台主机的平均负载，并为每个满足 avg(load1) > 10 的主机生成告警实例。

关键参数说明：

FOR：指定条件需要持续多久才会进入 firing 状态
KEEP FIRING FOR：指定条件不再满足后，告警实例在 firing 状态保持多久

详见 Trigger 语法。

3. 查看 Trigger 状态

列出所有 Trigger

SHOW TRIGGERS;

输出：

+---------------+
| Triggers      |
+---------------+
| load1_monitor |
+---------------+

查看创建语句

SHOW CREATE TRIGGER `load1_monitor`\G

输出：

*************************** 1. row ***************************
       Trigger: load1_monitor
Create Trigger: CREATE TRIGGER IF NOT EXISTS `load1_monitor`
  ON (SELECT host AS label_host, avg(load1) AS avg_load1 ...) EVERY '1 minutes'::INTERVAL
  FOR '3 minutes'::INTERVAL
  KEEP FIRING FOR '3 minutes'::INTERVAL
  LABELS (severity = 'warning')
  ANNOTATIONS (comment = 'Your computer is smoking, should take a break.')
  NOTIFY(
    WEBHOOK `alert_manager` URL `http://localhost:9093` WITH (timeout = '1m'),
  )

查看 Trigger 详情

SELECT * FROM information_schema.triggers\G

输出：

*************************** 1. row ***************************
   trigger_name: load1_monitor
     trigger_id: 1024
        raw_sql: (SELECT host AS label_host, avg(load1) AS avg_load1, ...)
       interval: 60
         labels: {"severity":"warning"}
    annotations: {"comment":"Your computer is smoking, should take a break."}
            for: 180
keep_firing_for: 180
       channels: [{"channel_type":{"Webhook":{"opts":{"timeout":"1m"}, ...}]
    flownode_id: 0

关于更多字段说明，参见 Triggers。

查看告警实例

SELECT * FROM information_schema.alerts;

如果尚未写入数据，将返回空结果。

关于更多字段说明，参见 Alerts。

4. 写入数据并观察告警状态

下面的脚本模拟数据写入：先写入 1 分钟正常值，再写入 6 分钟的高值触发告警，随后恢复到正常值。

#!/usr/bin/env bash

MYSQL="mysql -h 127.0.0.1 -P 4002"

insert_normal() {
  $MYSQL -e "INSERT INTO load1 (host, load1, ts) VALUES
    ('newyork1', 1.2, now()),
    ('newyork2', 1.1, now()),
    ('newyork3', 1.3, now());"
}

insert_high() {
  $MYSQL -e "INSERT INTO load1 (host, load1, ts) VALUES
    ('newyork1', 1.2, now()),
    ('newyork2', 12.1, now()),
    ('newyork3', 11.5, now());"
}

# 第一分钟：正常数据
for i in {1..4}; do insert_normal; sleep 15; done

# 接下来 6 分钟：高负载
for i in {1..24}; do insert_high; sleep 15; done

# 之后：恢复正常
while true; do insert_normal; sleep 15; done

状态变迁

在另一个终端中查询告警状态：

阶段 1：无告警

SELECT * FROM information_schema.alerts\G

输出：

Empty set

阶段 2：pending（条件首次满足，未达 FOR 时长）

SELECT trigger_id, labels, active_at, fired_at, resolved_at FROM information_schema.alerts;

+------------+-----------------------------------------------------------------------+----------------------------+----------+-------------+
| trigger_id | labels                                                                | active_at                  | fired_at | resolved_at |
+------------+-----------------------------------------------------------------------+----------------------------+----------+-------------+
|       1024 | {"alert_name":"load1_monitor","host":"newyork3","severity":"warning"} | 2025-12-29 11:58:20.992670 | NULL     | NULL        |
|       1024 | {"alert_name":"load1_monitor","host":"newyork2","severity":"warning"} | 2025-12-29 11:58:20.992670 | NULL     | NULL        |
+------------+-----------------------------------------------------------------------+----------------------------+----------+-------------+

阶段 3：firing（满足 FOR，开始发送通知）

SELECT trigger_id, labels, active_at, fired_at, resolved_at FROM information_schema.alerts;

+------------+-----------------------------------------------------------------------+----------------------------+----------------------------+-------------+
| trigger_id | labels                                                                | active_at                  | fired_at                   | resolved_at |
+------------+-----------------------------------------------------------------------+----------------------------+----------------------------+-------------+
|       1024 | {"alert_name":"load1_monitor","host":"newyork3","severity":"warning"} | 2025-12-29 11:58:20.992670 | 2025-12-29 12:02:20.991713 | NULL        |
|       1024 | {"alert_name":"load1_monitor","host":"newyork2","severity":"warning"} | 2025-12-29 11:58:20.992670 | 2025-12-29 12:02:20.991713 | NULL        |
+------------+-----------------------------------------------------------------------+----------------------------+----------------------------+-------------+

阶段 4：inactive（条件不满足 + KEEP FIRING FOR 期满，发送恢复通知）

SELECT trigger_id, labels, active_at, fired_at, resolved_at FROM information_schema.alerts;

+------------+-----------------------------------------------------------------------+----------------------------+----------------------------+----------------------------+
| trigger_id | labels                                                                | active_at                  | fired_at                   | resolved_at                |
+------------+-----------------------------------------------------------------------+----------------------------+----------------------------+----------------------------+
|       1024 | {"alert_name":"load1_monitor","host":"newyork3","severity":"warning"} | 2025-12-29 11:58:20.992670 | 2025-12-29 12:02:20.991713 | 2025-12-29 12:05:20.991750 |
|       1024 | {"alert_name":"load1_monitor","host":"newyork2","severity":"warning"} | 2025-12-29 11:58:20.992670 | 2025-12-29 12:02:20.991713 | 2025-12-29 12:05:20.991750 |
+------------+-----------------------------------------------------------------------+----------------------------+----------------------------+----------------------------+

5. 集成 Alertmanager（可选）

如果已部署 Prometheus Alertmanager，GreptimeDB 会自动将 firing 和 inactive 状态的告警推送过去。

每次评估后，Trigger 会将查询结果中的字段注入 labels 和 annotations。本示例中， host 会作为 label，avg_load1 会作为 annotation。这些字段会传递到 Alertmanager，并可在通知模板中使用。

由于 payload 与 Alertmanager 兼容，你可以直接复用其分组、抑制、静默和路由能力，无需适配器。

参考资料

Trigger 语法: 与 TRIGGER 相关的 SQL 语句的语法细节
INFORMATION_SCHEMA.TRIGGERS: 关于 Trigger 元数据的视图
INFORMATION_SCHEMA.ALERTS: 关于告警实例元数据的视图

Trigger

关键特性​

快速入门示例​

1. 创建数据表​

2. 创建 Trigger​

3. 查看 Trigger 状态​

列出所有 Trigger​

查看创建语句​

查看 Trigger 详情​

查看告警实例​

4. 写入数据并观察告警状态​

状态变迁​

5. 集成 Alertmanager（可选）​

参考资料​