GROUP BY clause

Use the GROUP BY clause to group data by values.

GROUP BY is an optional clause used to group rows that have the same values for all columns and expressions in the list. To output an aggregation for each group, include an aggregate or selector function in the SELECT statement. When GROUP BY appears in a query, the SELECT list can only use columns that appear in the GROUP BY list or in aggregate expressions.

• Syntax
• Examples

Syntax

SELECT
  AGGREGATE_FN(field1),
  tag1
FROM measurement
GROUP BY tag1

Examples

Group data by tag values

SELECT
  AVG(water_level) AS avg_water_level,
  location
FROM h2o_feet
GROUP BY location

Group data into 15 minute time intervals by tag

SELECT
  location,
  DATE_BIN(INTERVAL '15 minutes', time) AS time,
  COUNT(water_level) AS count
FROM h2o_feet
WHERE 
  time >= timestamp '2019-09-17T00:00:00Z'
  AND time <= timestamp '2019-09-17T01:00:00Z'
GROUP BY 1, location
ORDER BY location, 1