The WHERE clause
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: 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'`
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
Select data with specific field key-values
SELECT * FROM "h2o_feet" WHERE "water_level" > 9
Output:
Name: h2o_feet
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.
Select data with a specific string field key-value
SELECT * FROM "h2o_feet" WHERE "level description" = 'below 3 feet'
Output:
Name: h2o_feet
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.
Select data with a specific field key-value and perform basic arithmetic
SELECT * FROM "h2o_feet" WHERE "water_level" + 2 > 11.9
Output:
Name: h2o_feet
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.
Select data with a specific tag key-value
SELECT "water_level" FROM "h2o_feet" WHERE "location" = 'santa_monica'
Output:
Name: h2o_feet
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.
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:
Name: h2o_feet
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.
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:
Name: h2o_feet
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:
Name: h2o_feet
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 |