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Use the WHERE clause to filter data based on fields, tags, and/or timestamps.

Syntax

SELECT_clause FROM_clause WHERE <conditional_expression> [(AND|OR) <conditional_expression> [...]]

The WHERE clause supports conditional_expressions on fields, tags, and timestamps.

{{% note %}} Note: InfluxDB does not support using OR in the WHERE clause to specify multiple time ranges. For example, InfluxDB returns an empty response for the following query:

SELECT * FROM "mydb" WHERE time = '2020-07-31T20:07:00Z' OR time = '2020-07-31T23:07:17Z'`

{{% /note %}}

Fields

field_key <operator> ['string' | boolean | float | integer]

The WHERE clause supports comparisons against string, boolean, float, and integer field values.

Single quote string field values in the WHERE clause. Queries with unquoted string field values or double quoted string field values will not return any data and, in most cases, will not return an error.

Supported operators

Operator Meaning
= equal to
<> not equal to
!= not equal to
> greater than
>= greater than or equal to
< less than
<= less than or equal to

InfluxQL also supports Regular Expressions.

Tags

tag_key <operator> ['tag_value']

Single quote tag values in the WHERE clause. Queries with unquoted tag values or double quoted tag values will not return any data and, in most cases, will not return an error.

Supported operators

Operator Meaning
= equal to
<> not equal to
!= not equal to

Timestamps

For most SELECT statements, the default time range is between 1677-09-21 00:12:43.145224194 and 2262-04-11T23:47:16.854775806Z UTC. For SELECT statements with a GROUP BY time() clause, the default time range is between 1677-09-21 00:12:43.145224194 UTC and now().

See Time Syntax for information on how to specify alternative time ranges in the WHERE clause.

Examples

{{< expand-wrapper >}} {{% expand "Select data with specific field key-values" %}}

SELECT * FROM "h2o_feet" WHERE "water_level" > 9

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

time level description location water_level
2019-08-25T04:00:00Z at or greater than 9 feet coyote_creek 9.0320000000
2019-08-25T04:06:00Z at or greater than 9 feet coyote_creek 9.0780000000
2019-08-25T04:12:00Z at or greater than 9 feet coyote_creek 9.1110000000
2019-08-25T04:18:00Z at or greater than 9 feet coyote_creek 9.1500000000
2019-08-25T04:24:00Z at or greater than 9 feet coyote_creek 9.1800000000

The query returns data from the h2o_feet measurement with field values of water_level that are greater than nine. This is a partial data set.

{{% /expand %}}

{{% expand "Select data with a specific string field key-value" %}}

SELECT * FROM "h2o_feet" WHERE "level description" = 'below 3 feet'

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

time level description location water_level
2019-08-17T00:00:00Z below 3 feet santa_monica 2.0640000000
2019-08-17T00:06:00Z below 3 feet santa_monica 2.1160000000
2019-08-17T00:12:00Z below 3 feet santa_monica 2.0280000000
2019-08-17T00:18:00Z below 3 feet santa_monica 2.1260000000
2019-08-17T00:24:00Z below 3 feet santa_monica 2.0410000000
2019-08-17T00:30:00Z below 3 feet santa_monica 2.0510000000

The query returns data from the h2o_feet measurement with field values of level description that equal the below 3 feet string. InfluxQL requires single quotes around string field values in the WHERE clause.

{{% /expand %}}

{{% expand "Select data with a specific field key-value and perform basic arithmetic" %}}

SELECT * FROM "h2o_feet" WHERE "water_level" + 2 > 11.9

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

time level description location water_level
2019-08-28T07:06:00Z at or greater than 9 feet coyote_creek 9.9020000000
2019-08-28T07:12:00Z at or greater than 9 feet coyote_creek 9.9380000000
2019-08-28T07:18:00Z at or greater than 9 feet coyote_creek 9.9570000000
2019-08-28T07:24:00Z at or greater than 9 feet coyote_creek 9.9640000000
2019-08-28T07:30:00Z at or greater than 9 feet coyote_creek 9.9540000000
2019-08-28T07:36:00Z at or greater than 9 feet coyote_creek 9.9410000000
2019-08-28T07:42:00Z at or greater than 9 feet coyote_creek 9.9250000000
2019-08-28T07:48:00Z at or greater than 9 feet coyote_creek 9.9020000000
2019-09-01T23:30:00Z at or greater than 9 feet coyote_creek 9.9020000000

The query returns data from the h2o_feet measurement with field values of water_level plus two that are greater than 11.9. Note that InfluxDB follows the standard order of operations.

See Mathematical operators for more on supported operators.

{{% /expand %}}

{{% expand "Select data with a specific tag key-value" %}}

SELECT "water_level" FROM "h2o_feet" WHERE "location" = 'santa_monica'

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

time water_level
2019-08-17T00:00:00Z 2.0640000000
2019-08-17T00:06:00Z 2.1160000000
2019-08-17T00:12:00Z 2.0280000000
2019-08-17T00:18:00Z 2.1260000000
2019-08-17T00:24:00Z 2.0410000000

The query returns data from the h2o_feet measurement where the tag key location is set to santa_monica. InfluxQL requires single quotes around tag values in the WHERE clause.

{{% /expand %}}

{{% expand "Select data with specific field key-values and tag key-valuest" %}}

SELECT "water_level" FROM "h2o_feet" WHERE "location" <> 'santa_monica' AND (water_level < -0.59 OR water_level > 9.95)

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

time water_level
2019-08-28T07:18:00Z 9.9570000000
2019-08-28T07:24:00Z 9.9640000000
2019-08-28T07:30:00Z 9.9540000000
2019-08-28T14:30:00Z -0.6100000000
2019-08-28T14:36:00Z -0.5910000000
2019-08-29T15:18:00Z -0.5940000000

The query returns data from the h2o_feet measurement where the tag key location is not set to santa_monica and where the field values of water_level are either less than -0.59 or greater than 9.95. The WHERE clause supports the operators AND and OR, and supports separating logic with parentheses.

{{% /expand %}}

{{< /expand-wrapper >}}

SELECT * FROM "h2o_feet" WHERE time > now() - 7d

The query returns data from the h2o_feet measurement with timestamps within the past seven days. See Time Syntax for more in-depth information on supported time syntax in the WHERE clause.

Common issues with the WHERE clause

A WHERE clause query unexpectedly returns no data

In most cases, this issue is the result of missing single quotes around tag values or string field values. Queries with unquoted or double quoted tag values or string field values will not return any data and, in most cases, will not return an error.

The first two queries in the code block below attempt to specify the tag value santa_monica without any quotes and with double quotes. Those queries return no results. The third query single quotes santa_monica (this is the supported syntax) and returns the expected results.

SELECT "water_level" FROM "h2o_feet" WHERE "location" = santa_monica
No results

SELECT "water_level" FROM "h2o_feet" WHERE "location" = "santa_monica"
No results

SELECT "water_level" FROM "h2o_feet" WHERE "location" = 'santa_monica'

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

time water_level
2019-08-17T00:00:00Z 2.0640000000
2019-08-17T00:06:00Z 2.1160000000
2019-08-17T00:12:00Z 2.0280000000
2019-08-17T00:18:00Z 2.1260000000
2019-08-17T00:24:00Z 2.0410000000
2019-08-17T00:30:00Z 2.0510000000

The first two queries in the code block below attempt to specify the string field value at or greater than 9 feet without any quotes and with double quotes. The first query returns an error because the string field value includes white spaces. The second query returns no results. The third query single quotes at or greater than 9 feet (this is the supported syntax) and returns the expected results.

SELECT "level description" FROM "h2o_feet" WHERE "level description" = at or greater than 9 feet
ERR: 400 Bad Request: failed to parse query: found than, expected ; at line 1, char 86

SELECT "level description" FROM "h2o_feet" WHERE "level description" = "at or greater than 9 feet"
No results

SELECT "level description" FROM "h2o_feet" WHERE "level description" = 'at or greater than 9 feet'

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

time level_description
2019-08-25T04:00:00Z at or greater than 9 feet
2019-08-25T04:06:00Z at or greater than 9 feet
019-08-25T04:12:00Z at or greater than 9 feet
2019-08-25T04:18:00Z at or greater than 9 feet
2019-08-25T04:24:00Z at or greater than 9 feet