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InfluxDB

Configuration

/etc/influxdb/influxdb.conf

[http]
  auth-enabled = true
Management

Create a new user and database

influx
> CREATE USER admin WITH PASSWORD 'adminpass' WITH ALL PRIVILEGES
> exit

influx -username admin -password adminpass
> set password for admin = 'newpass'
>
> create database mmap_nmon
> create user mon with password 'thisispassword'
> grant all on mmap_nmon to mon

Login to InfluxDB

# In the shell
influx -username admin -password thisispass

# In the InfluxDB CLI
> auth
username:
password

InfluxQL

> show databases
name: databases
name
----
_internal
nmon_reports
nmon2influxdb_log

> show users
user  admin
----  -----
admin true
mon   false

> use nmon_reports
Using database nmon_reports
> show measurements
name: measurements
name
----
CPU_ALL
DISKAVGRIO
DISKAVGWIO
DISKBSIZE
DISKBUSY
DISKREAD
DISKREADSERV
DISKRIO
DISKRXFER
DISKSERV
...

Retention Policy

# for current database
> show retention policies
name    duration  shardGroupDuration replicaN default
----    --------  ------------------ -------- -------
autogen 8760h0m0s 168h0m0s           1        true

# for specified database
> show retention policies on nmon2influxdb_log
name          duration shardGroupDuration replicaN default
----          -------- ------------------ -------- -------
autogen       0s       168h0m0s           1        false
log_retention 48h0m0s  24h0m0s            1        true

# Create a policy
> CREATE RETENTION POLICY "one_day_only" ON "NOAA_water_database" DURATION 1d REPLICATION 1

# Alter the policy
> ALTER RETENTION POLICY "what_is_time" ON "NOAA_water_database" DURATION 3w SHARD DURATION 2h DEFAULT

# Delete a policy
> DROP RETENTION POLICY "what_is_time" ON "NOAA_water_database"

Verify the account

curl -G http://localhost:8086/query -u mon:thisispassword --data-urlencode "q=SHOW DATABASES"
{"results":[{"statement_id":0,"series":[{"name":"databases","columns":["name"],"values":[["mmap_nmon"]]}]}]}

查詢表資訊

SHOW MEASUREMENTS  --查詢當前資料庫中含有的表
SHOW FIELD KEYS --查看當前資料庫所有表的欄位
SHOW series from pay --查看key數據
SHOW TAG KEYS FROM "pay" --查看key中tag key值
SHOW TAG VALUES FROM "pay" WITH KEY = "merId" --查看key中tag 指定key值對應的值
SHOW TAG VALUES FROM cpu WITH KEY IN ("region", "host") WHERE service = 'redis'
DROP SERIES FROM  WHERE ='' --刪除key
SHOW CONTINUOUS QUERIES   --查看連續執行命令
SHOW QUERIES  --查看最後執行命令
KILL QUERY  --結束命令
SHOW RETENTION POLICIES ON mydb  --查看保留數據

查詢資料

SELECT * FROM /.*/ LIMIT 1  --查詢當前資料庫下所有表的第一行記錄
select * from pay  order by time desc limit 2
select * from  db_name."POLICIES name".measurement_name --指定查詢資料庫下資料保留中的表資料 POLICIES name資料保留

刪除資料

delete from "query" --刪除表所有資料，則表就不存在了
drop MEASUREMENT "query"   --刪除表（注意會把資料保留刪除使用delete不會）
DELETE FROM cpu
DELETE FROM cpu WHERE time < '2000-01-01T00:00:00Z'
DELETE WHERE time < '2000-01-01T00:00:00Z'
DROP DATABASE “testDB” --刪除資料庫
DROP RETENTION POLICY "dbbak" ON mydb --刪除保留資料為dbbak資料
DROP SERIES from pay where tag_key='' --刪除key中的tag

函數使用

  • mean-平均值
  • sum-總和
  • min-最小值
  • max-最大值
  • count-總個數
select * from pay   order by time desc limit 2
select mean(allTime) from pay where time >= today() group by time(10m) time_zone(+8)
select * from pay time_zone(+8) limit 2
SELECT sum(allTime) FROM "pay" WHERE time > now() - 10s
select count(allTime) from pay  where time > now() - 10m  group by time(1s)

 

Services
systemctl start influxdb
systemctl enable influxdb

 

 

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