65 lines
2.0 KiB
Go
65 lines
2.0 KiB
Go
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/*
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Package influxql implements a parser for the InfluxDB query language.
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InfluxQL is a DML and DDL language for the InfluxDB time series database.
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It provides the ability to query for aggregate statistics as well as create
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and configure the InfluxDB server.
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Selecting data
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The SELECT query is used for retrieving data from one or more series. It allows
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for a list of columns followed by a list of series to select from.
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SELECT value FROM cpu_load
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You can also add a a conditional expression to limit the results of the query:
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SELECT value FROM cpu_load WHERE host = 'influxdb.com'
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Two or more series can be combined into a single query and executed together:
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SELECT cpu0.value + cpu1.value
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FROM cpu_load AS cpu0 INNER JOIN cpu_load cpu1 ON cpu0.host = cpu1.host
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Limits and ordering can be set on selection queries as well:
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SELECT value FROM cpu_load LIMIT 100 ORDER DESC;
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Removing data
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The DELETE query is available to remove time series data points from the
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database. This query will delete "cpu_load" values older than an hour:
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DELETE FROM cpu_load WHERE time < now() - 1h
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Continuous Queries
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Queries can be run indefinitely on the server in order to generate new series.
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This is done by running a "SELECT INTO" query. For example, this query computes
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the hourly mean for cpu_load and stores it into a "cpu_load" series in the
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"daily" shard space.
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SELECT mean(value) AS value FROM cpu_load GROUP BY 1h
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INTO daily.cpu_load
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If there is existing data on the source series then this query will be run for
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all historic data. To only execute the query on new incoming data you can append
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"NO BACKFILL" to the end of the query:
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SELECT mean(value) AS value FROM cpu_load GROUP BY 1h
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INTO daily.cpu_load NO BACKFILL
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Continuous queries will return an id that can be used to remove them in the
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future. To remove a continous query, use the DROP CONTINUOUS QUERY statement:
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DROP CONTINUOUS QUERY 12
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You can also list all continuous queries by running:
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LIST CONTINUOUS QUERIES
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*/
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package influxql
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