influxdb/QUERIES.md

The top level name is called a measurement. These names can contain any characters. Then there are field names, field values, tag keys and tag values, which can also contain any characters. Because of this, anywhere a measurement name, field name, field value, tag name, or tag value appears should be able to get wrapped in double quotes to deal with special characters.

Select

-- get the top 10 host measurements for the last hour (same host can appear multiple times)
SELECT top(10, value), host FROM cpu WHERE time > now() - 1h

-- get the top 10 unique hosts for the last hour
SELECT top(10, value), distinct(host) FROM cpu WHERE time > now() - 1h

Group By

Delete

Series

Destroy

DROP MEASUREMENT <name>
DROP MEASUREMENT cpu WHERE region = 'uswest'

List

List series queries are for pulling out individual series from measurement names and tag data. They're useful for discovery.

-- list all series across all measurements/tagsets
LIST SERIES

-- get a list of all series for any measurements where tag key region = tak value 'uswest'
LIST SERIES WHERE region = 'uswest'

-- get a list of all tag keys across all measurements
LIST KEYS

-- list all the tag keys for a given measurement
LIST KEYS FROM cpu
LIST KEYS FROM temperature, wind_speed

-- list all the tag values. note that at least one WHERE key = '...' clause is required
LIST VALUES WHERE key = 'region'
LIST VALUES FROM cpu WHERE region = 'uswest' and key = 'host'

Note that FROM and WHERE are optional clauses in all of the list series queries.

And the list series output looks like this:

[
    {
        "name": "cpu",
        "columns": ["id", "region", "host"],
        "values": [
            1, "uswest", "servera",
            2, "uswest", "serverb"
        ]
    },
    {
        "name": "reponse_time",
        "columns": ["id", "application", "host"],
        "values": [
            3, "myRailsApp", "servera"
        ]
    }
]

Continuous Queries

Continous queries are going to be inspired by MySQL TRIGGER syntax:

http://dev.mysql.com/doc/refman/5.0/en/trigger-syntax.html

Instead of having automatically-assigned ids, named continuous queries allows for some level of duplication prevention, particularly in the case where creation is scripted.

Create

CREATE CONTINUOUS QUERY <name> AS SELECT ... FROM ...

Destroy

DROP CONTINUOUS QUERY <name>

List

LIST CONTINUOUS QUERIES