docs-v2/content/shared/influxdb3-query-guides/sql/basic-query.md

The InfluxDB SQL implementation is powered by the Apache Arrow DataFusion query engine which provides an SQL syntax similar to other relational query languages.

A basic SQL query that queries data from {{< product-name >}} most commonly includes the following clauses:

{{< req type="key" >}}

• {{< req "*">}} SELECT: Specify fields, tags, and calculations to output from a table or use the wildcard alias (*) to select all fields and tags from a table.
• {{< req "*">}} FROM: Specify the table to query data from.
• WHERE: Only return rows that meets the specified conditions--for example, the time is within a time range, a tag has a specific value, or a field value is above or below a specified threshold.

{{% influxdb/custom-timestamps %}}

SELECT
  temp,
  hum,
  room
FROM home
WHERE
  time >= '2022-01-01T08:00:00Z'
  AND time <= '2022-01-01T20:00:00Z'

{{% /influxdb/custom-timestamps %}}

Result set

If at least one row satisfies the query, {{% product-name %}} returns row data in the query result set. An SQL query result set includes columns listed in the query's SELECT statement.

Basic query examples

• Query data within time boundaries
• Query data without time boundaries
• Query specific fields and tags
• Query fields based on tag values
• Query points based on field values
• Alias queried fields and tags

[!Note]

Sample data

The following examples use the Home sensor sample data. To run the example queries and return results, write the sample data to your {{% product-name %}} database before running the example queries.

Query data within time boundaries

• Use the SELECT clause to specify what tags and fields to return. To return all tags and fields, use the wildcard alias (*).
• Specify the table to query in the FROM clause.
• Specify time boundaries in the WHERE clause. Include time-based predicates that compare the value of the time column to a timestamp. Use the AND logical operator to chain multiple predicates together.

{{% influxdb/custom-timestamps %}}

SELECT *
FROM home
WHERE
  time >= '2022-01-01T08:00:00Z'
  AND time <= '2022-01-01T12:00:00Z'

{{% /influxdb/custom-timestamps %}}

Query time boundaries can be relative or absolute.

{{< expand-wrapper >}} {{% expand "Query with relative time boundaries" %}}

To query data from relative time boundaries, compare the value of the time column to a timestamp calculated by subtracting an interval from a timestamp. Use now() to return the timestamp for the current time (UTC).

Query all data from the last month

SELECT * FROM home WHERE time >= now() - INTERVAL '1 month'

Query one day of data data from a week ago

SELECT *
FROM home
WHERE
  time >= now() - INTERVAL '7 days'
  AND time <= now() - INTERVAL '6 days'

{{% /expand %}}

{{% expand "Query with absolute time boundaries" %}}

To query data from absolute time boundaries, compare the value of the time column to a timestamp literal. Use the AND logical operator to chain together multiple predicates and define both start and stop boundaries for the query.

{{% influxdb/custom-timestamps %}}

SELECT
  *
FROM
  home
WHERE
  time >= '2022-01-01T08:00:00Z'
  AND time <= '2022-01-01T20:00:00Z'

{{% /influxdb/custom-timestamps %}}

{{% /expand %}}

{{% expand "Query data using a time zone offset" %}}

To query data using a time zone offset, use the AT TIME ZONE operator to apply a time zone offset to timestamps in the WHERE clause.

[!Note] Timestamp types in InfluxDB always represent a UTC time. AT TIME ZONE returns a UTC timestamp adjusted for the offset of the specified time zone. Timestamps in the time column are not updated. If you need to display the timestamps in your current timezone, this should be handled client-side.

{{% influxdb/custom-timestamps %}}

SELECT
  *
FROM
  home
WHERE
  time >= '2022-01-01 00:00:00'::TIMESTAMP AT TIME ZONE 'America/Los_Angeles'
  AND time <= '2022-01-01 12:00:00'::TIMESTAMP AT TIME ZONE 'America/Los_Angeles'

{{% /influxdb/custom-timestamps %}} {{% /expand %}} {{< /expand-wrapper >}}

Query data without time boundaries

To query data without time boundaries, do not include any time-based predicates in your WHERE clause.

[!Warning] Querying data without time bounds can return an unexpected amount of data. The query may take a long time to complete and results may be truncated.

SELECT * FROM home

Query specific fields and tags

To query specific fields, include them in the SELECT clause. If querying multiple fields or tags, comma-delimit each. If a field or tag key includes special characters or spaces or is case-sensitive, wrap the key in double-quotes.

SELECT time, room, temp, hum FROM home

Query fields based on tag values

• Include the fields you want to query and the tags you want to base conditions on in the SELECT clause.
• Include predicates in the WHERE clause that compare the tag identifier to a string literal. Use logical operators to chain multiple predicates together and apply multiple conditions.

SELECT * FROM home WHERE room = 'Kitchen'

Query points based on field values

• In the SELECT clause, include fields you want to query.
• In the WHERE clause, include predicates that compare the field identifier to a value or expression. Use logical operators (AND, OR) to chain multiple predicates together and apply multiple conditions.

SELECT co, time FROM home WHERE co >= 10 OR co <= -10

Alias queried fields and tags

To alias or rename fields and tags that you query, pass a string literal after the field or tag identifier in the SELECT clause. You can use the AS clause to define the alias, but it isn't necessary. The following queries are functionally the same:

SELECT temp 'temperature', hum 'humidity' FROM home

SELECT temp AS 'temperature', hum AS 'humidity' FROM home