Left join in influx DB

问题

I am new to influx DB. Now I need to migrate MySQL db into influxDB. I chose influx DB because it support SQL like queries. But I could not found left join in it. I have a series called statistics which contains browser_id and another series contains browser list. How can I join these 2 tables like relational database concept? I wrote this query but it is not giving any result.

select * from statistics as s inner join browsers as b where s.browser_type_id  = b.id

statistics

browsers

回答1:

You cannot join series in InfluxDB using arbitrary columns. InfluxDB only supports joining time series based on the time column. This is a special type of join unlike the one you're used to in relational databases. Time join in InfluxDB tries to correlate points from different time series that happened at approximately the same time. You can read more about joins in InfluxDB in the docs

回答2:

Seems that now is possible. Check again documentation: https://docs.influxdata.com/influxdb/v0.8/api/query_language/#joining-series

select hosta.value + hostb.value
from cpu_load as hosta
inner join cpu_load as hostb
where hosta.host = 'hosta.influxdb.orb' and hostb.host = 'hostb.influxdb.org';

来源：https://stackoverflow.com/questions/26376807/left-join-in-influx-db