1. 与MySQL的比较

InfluxDB	MySQL	解释
Bucket	Database	数据库
Measurement	Table	表
Tag	Indexed Column	索引列
Field	Column	普通列
Point	Row	每行数据

2. 安装FluxDB

brew update

默认安装 2.x的版本

brew install influxdb

查看influxdb版本

influxd version # InfluxDB 2.7.11 (git: fbf5d4ab5e) build_date: 2024-11-26T18:06:07Z

启动influxdb

influxd

访问面板

http://localhost:8086/

配置用户信息

保存token

L5IeK5vutRmkCuyzbz781GVKj4fR6fKGQdl3CaWAPNEKmigrI0Yt8IlEN5_qkO9Lgb80BpcISK0U4WSkWDcqIQ==

3. 使用行协议写入数据

官网规范

• 首先是一个measurementName，和指定MySQL的表名一样
• 然后是Tag，和指定MySQL的索引列一样，多个Tag通过逗号分隔
• 然后是Field，和指定MySQL的普通列一样多个Field通过逗号分隔，与Tag通过空格分隔
• 最后是时间戳(选填，下面测试时单位为秒)

测试写入：

user,name=jack age=11 1748264631

结果：

4. 使用Flux查询数据

• from：从哪个Bucket即桶中查询数据
• range：根据时间筛选数据，单位有ms毫秒，s秒，m分钟，h消失，d天，w星期，mo月，y年，比如range(start: -1d, stop:now())就是过去一天内的数据，其中stop:now()是默认的，可以不写。
• filter：根据列筛选数据

样例并解释：

from(bucket: "demo") # 从demo这个数据库中去数据
    |> range(start: -1d, stop:now()) # 时间范围筛选
    |> filter(fn: (r) => r["_measurement"] == "user") # 从这个user这个表查询数据
    |> filter(fn: (r) => r["name"] == "jack") # 根据索引等值查询，相当于MySQL后面的where条件，influx会根据这个tag上的倒排索引加快查询速度
    |> filter(fn: (r) => r["_field"] == "age") # 相当于MySQL查询具体的列的数据，只不过有多个Field会被拆分为多行，每行对应一个Field的数据

关于r["_field"] == "age"的问题：为什么需要这么查询？因为Field如果有多个，就会被拆成多行
比如我们插入数据时是这样的：user,name=jack age=18,height=180 1716715200000000000，虽然这是一个数据点Point，但是由于有两个Field，那么查询到的数据其实是两行，如果加了r["_field"] == "age"，就只会出现第一条数据，注意Tag不会被拆分为多行

_measurement	name	_field	_value	_time
user	jack	age	18	2024-05-26 00:00:00Z
user	jack	height	180	2024-05-26 00:00:00Z

5. SpringBoot集成

5.1 引入依赖

<dependency>
    <groupId>com.influxdb</groupId>
    <artifactId>influxdb-client-java</artifactId>
    <version>6.9.0</version>
</dependency>
<dependency>
    <groupId>org.jetbrains.kotlin</groupId>
    <artifactId>kotlin-stdlib</artifactId>
    <version>1.8.20</version>
</dependency>

5.2. 插入数据

5.2.1 基础数据

private final static String token = "L5IeK5vutRmkCuyzbz781GVKj4fR6fKGQdl3CaWAPNEKmigrI0Yt8IlEN5_qkO9Lgb80BpcISK0U4WSkWDcqIQ==";
private final static String org = "test";
private final static String bucket = "demo";
private final static String url = "http://127.0.0.1:8086";

5.2.2 通过行协议插入

private static void writeDataByLine() {
    InfluxDBClient influxDBClient = InfluxDBClientFactory.create(url, token.toCharArray());
    WriteApiBlocking writeApi = influxDBClient.getWriteApiBlocking();
    String data = "user,name=tom age=18 1748270504";
    writeApi.writeRecord(bucket, org, WritePrecision.S, data);
}

5.2.3 通过Point插入

private static void writeDataByPoint() {
    InfluxDBClient influxDBClient = InfluxDBClientFactory.create(url, token.toCharArray());
    WriteApiBlocking writeApi = influxDBClient.getWriteApiBlocking();
    Point point = Point.measurement("user")
            .addTag("name", "jerry")
            .addField("age", 20f)
            .time(Instant.now(), WritePrecision.S);
    writeApi.writePoint(bucket, org, point);
}

5.2.4 通过Pojo类插入

import com.influxdb.annotations.Column;
import com.influxdb.annotations.Measurement;
import lombok.AllArgsConstructor;
import lombok.NoArgsConstructor;

import java.time.Instant;

@Measurement(name = "user")
@NoArgsConstructor
@AllArgsConstructor
public class InfluxData {
    @Column(tag = true)
    String name;
    @Column
    Float age;
    @Column(timestamp = true)
    Instant time;
}

private static void writeDataByPojo() {
    InfluxDBClient influxDBClient = InfluxDBClientFactory.create(url, token.toCharArray());
    WriteApiBlocking writeApi = influxDBClient.getWriteApiBlocking();
    InfluxData influxData = new InfluxData("cat", 30f, Instant.now());
    writeApi.writeMeasurement(bucket, org, WritePrecision.S, influxData);
}

5.3 查询数据

private static void queryData() {
    InfluxDBClient influxDBClient = InfluxDBClientFactory.create(url, token.toCharArray());
    String query = "from(bucket: \"demo\")\n" +
            "    |> range(start: -1d, stop:now())\n" +
            "    |> filter(fn: (r) => r[\"_measurement\"] == \"user\")";
    List<FluxTable> fluxTables = influxDBClient.getQueryApi().query(query, org);
    for (FluxTable fluxTable : fluxTables) {// 根据索引列分组
        for (FluxRecord record : fluxTable.getRecords()) { // 每组的数据
            System.out.println(record.getValues());
        }
        System.out.println();
    }
}

最终结果：

5.4 查询升级

自定义查询参数，时间范围查询

@Data
public class InfluxDataQuery {
    private String plcName;
    @DateTimeFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    private LocalDateTime startTime;
    @DateTimeFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    private LocalDateTime stopTime;
    private String topic;
}

public List<Map<String, Object>> queryData(InfluxDataQuery queryParams) {
    String plcName = queryParams.getPlcName();
    LocalDateTime startTime = queryParams.getStartTime(), stopTime = queryParams.getStopTime();
    String topic = queryParams.getTopic();
    if (startTime == null) {
        throw new RuntimeException("startTime不能为空");
    }
    InfluxDBClient influxDBClient = InfluxDBClientFactory.create(url, token.toCharArray());
    StringBuilder sb = new StringBuilder();
    sb.append("\nfrom(bucket: \"").append(bucket).append("\")\n");
    if (stopTime == null) {
        stopTime = LocalDateTime.now();
    }
    sb.append("    |> range(start:").append(startTime.atOffset(ZoneOffset.UTC).format(DateTimeFormatter.ISO_OFFSET_DATE_TIME))
            .append(",stop:").append(stopTime.atOffset(ZoneOffset.UTC).format(DateTimeFormatter.ISO_OFFSET_DATE_TIME)).append(")\n");
    if (StringUtils.hasText(plcName)) {
        sb.append("    |> filter(fn: (r) => r[\"plcName\"] == \"").append(plcName).append("\")\n");
    }
    if (StringUtils.hasText(topic)) {
        sb.append("    |> filter(fn: (r) => r[\"_measurement\"] == \"").append(topic).append("\")\n");
    }
    log.info("query: {}", sb);
    List<FluxTable> fluxTables = influxDBClient.getQueryApi().query(sb.toString(), org);
    List<Map<String, Object>> dataList = new ArrayList<>();
    for (FluxTable fluxTable : fluxTables) {// 根据索引列分组
        for (FluxRecord record : fluxTable.getRecords()) { // 每组的数据
            dataList.add(record.getValues());
        }
    }

    return dataList;
}

拼接好的SQL大概长这样子：