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Use LIMIT and SLIMIT to limit the number of points and series returned per query.

LIMIT clause

LIMIT <N> returns the first N points from the specified measurement.

Syntax

SELECT_clause FROM_clause [WHERE_clause] [GROUP_BY_clause] [ORDER_BY_clause] LIMIT <N>

N specifies the number of points to return from the specified measurement . If N is greater than the number of points in a measurement, InfluxDB returns all points from the measurement.

{{% note %}} IMPORTANT: The LIMIT clause must appear in the order outlined in the syntax above. {{% /note %}}

Examples

{{< expand-wrapper >}}

{{% expand "Limit the number of points returned" %}}

SELECT "water_level","location" FROM "h2o_feet" LIMIT 3

Output: {{% influxql/table-meta %}} Name: h2o_feet {{% /influxql/table-meta %}}

time water_level location
2019-08-17T00:00:00Z 8.1200000000 coyote_creek
2019-08-17T00:00:00Z 2.0640000000 santa_monica
2019-08-17T00:06:00Z 8.0050000000 coyote_creek

The query returns the three oldest points, determined by timestamp, from the h2o_feet measurement.

{{% /expand %}}

{{% expand "Limit the number of points returned and include a GROUP BY clause" %}}

SELECT MEAN("water_level") FROM "h2o_feet" WHERE time >= '2019-08-18T00:00:00Z' AND time <= '2019-08-18T00:42:00Z' GROUP BY *,time(12m) LIMIT 2

Output:
{{% influxql/table-meta %}} name: h2o_feet
tags: location=coyote_creek {{% /influxql/table-meta %}}

time mean
2019-08-18T00:00:00Z 8.4615000000
2019-08-18T00:12:00Z 8.2725000000

{{% influxql/table-meta %}} name: h2o_feet
tags: location=santa_monica {{% /influxql/table-meta %}}

time mean
2019-08-18T00:00:00Z 2.3655000000
2019-08-18T00:12:00Z 2.3360000000

This query uses the InfluxQL MEAN() function and a GROUP BY clause to calculate the average water_level for each tag and for each 12-minute interval in the queried time range. LIMIT 2 requests the two oldest 12-minute averages (determined by timestamp).

Note that without LIMIT 2, the query would return four points per series; one for each 12-minute interval in the queried time range.

{{% /expand %}}

{{< /expand-wrapper >}}

SLIMIT clause

SLIMIT <N> returns every point from N series in the specified measurement.

Syntax

SELECT_clause FROM_clause [WHERE_clause] GROUP BY *[,time(<time_interval>)] [ORDER_BY_clause] SLIMIT <N>

N specifies the number of series to return from the specified measurement. If N is greater than the number of series in a measurement, InfluxDB returns all series from that measurement.

SLIMIT queries must include GROUP BY *. Note that the SLIMIT clause must appear in the order outlined in the syntax above.

Examples

{{< expand-wrapper >}}

{{% expand "Limit the number of series returned" %}}

SELECT "water_level" FROM "h2o_feet" GROUP BY * SLIMIT 1

Output:
{{% influxql/table-meta %}} name: h2o_feet
tags: location=coyote_creek {{% /influxql/table-meta %}}

time water_level
2019-08-17T00:00:00Z 8.1200000000
2019-08-17T00:06:00Z 8.0050000000
2019-08-17T00:12:00Z 7.8870000000
2019-08-17T00:18:00Z 7.7620000000
2019-08-17T00:24:00Z 7.6350000000
2019-08-17T00:30:00Z 7.5000000000
2019-08-17T00:36:00Z 7.3720000000

The results above include only the first few rows, as the data set is quite large. The query returns all water_level points from one of the series associated with the h2o_feet measurement.

{{% /expand %}}

{{% expand "Limit the number of series returned and include a GROUP BY time() clause" %}}

SELECT MEAN("water_level") FROM "h2o_feet" WHERE time >= '2019-08-18T00:00:00Z' AND time <= '2019-08-18T00:42:00Z' GROUP BY *,time(12m) SLIMIT 1

Output:
{{% influxql/table-meta %}} name: h2o_feet
tags: location=coyote_creek {{% /influxql/table-meta %}}

time mean
2019-08-18T00:00:00Z 8.4615000000
2019-08-18T00:12:00Z 8.2725000000
2019-08-18T00:24:00Z 8.0710000000
2019-08-18T00:36:00Z 7.8330000000

The query uses the InfluxQL MEAN() function and a time interval in the GROUP BY clause to calculate the average water_level for each 12-minute interval in the queried time range.

SLIMIT 1 requests a single series associated with the h2o_feet measurement.

Note that without SLIMIT 1, the query would return results for the two series associated with the h2o_feet measurement: location=coyote_creek and location=santa_monica.

{{% /expand %}}

{{< /expand-wrapper >}}

Use LIMIT and SLIMIT together

LIMIT <N> followed by SLIMIT <2> returns the first N1 points from N2 series in the specified measurement.

Syntax

SELECT_clause FROM_clause [WHERE_clause] GROUP BY *[,time(<time_interval>)] [ORDER_BY_clause] LIMIT <N1> SLIMIT <N2>

N1 specifies the number of points to return per measurement. If N1 is greater than the number of points in a measurement, InfluxDB returns all points from that measurement.

N2 specifies the number of series to return from the specified measurement. If N2 is greater than the number of series in a measurement, InfluxDB returns all series from that measurement.

SLIMIT queries must include GROUP BY *. Note that the SLIMIT clause must appear in the order outlined in the syntax above.

Examples

{{< expand-wrapper >}}

{{% expand "Limit the number of points and series returned" %}}

SELECT "water_level" FROM "h2o_feet" GROUP BY * LIMIT 3 SLIMIT 1

Output: {{% influxql/table-meta %}} Name: h2o_feet
Tags: location=coyote_creek {{% /influxql/table-meta %}}

time water_level
2019-08-17T00:00:00Z 8.1200000000
2019-08-17T00:06:00Z 8.0050000000
2019-08-17T00:12:00Z 7.8870000000

The query returns the three oldest points, determined by timestamp, from one of the series associated with the measurement h2o_feet.

{{% /expand %}}

{{% expand "Limit the number of points and series returned and include a GROUP BY time() clause" %}}

SELECT MEAN("water_level") FROM "h2o_feet" WHERE time >= '2019-08-18T00:00:00Z' AND time <= '2019-08-18T00:42:00Z' GROUP BY *,time(12m) LIMIT 2 SLIMIT 1

Output: {{% influxql/table-meta %}} Name: h2o_feet
Tags: location=coyote_creek {{% /influxql/table-meta %}}

time mean
2019-08-18T00:00:00Z 8.4615000000
2019-08-18T00:12:00Z 8.2725000000

The query uses the InfluxQL function MEAN() and a time interval in the GROUP BY clause to calculate the average water_level for each 12-minute interval in the queried time range. LIMIT 2 requests the two oldest 12-minute averages (determined by timestamp) and SLIMIT 1 requests a single series associated with the h2o_feet measurement.

Note that without LIMIT 2 SLIMIT 1, the query would return four points for each of the two series associated with the h2o_feet measurement.

{{% /expand %}}

{{< /expand-wrapper >}}