# Summarise by group Shape / table group by and summarise Page: ## Status Runs as a SQL step. arcform carries it as a `sql:` step today. ## The DuckDB step group and summarise It reads the `orders` table the proofs share. Create it first: ```sql CREATE TABLE orders AS SELECT * FROM (VALUES (1, 'Alice Ng', 'north', DATE '2026-01-03', 120.00, 'widget', 'a|b', '{"channel":"web","items":[1,2]}'), (2, 'alice ng', 'north', DATE '2026-01-05', 80.50, 'gadget', 'b', '{"channel":"shop","items":[3]}'), (3, 'Bob Okafor', 'south', DATE '2026-01-05', 300.00, 'widget', 'a|c', '{"channel":"web","items":[4,5,6]}'), (4, 'Carla Díaz', 'east', DATE '2026-01-09', NULL, 'gizmo', NULL, '{"channel":"web","items":[]}'), (5, 'Bob Okafor', 'south', DATE '2026-01-12', 45.25, 'gadget', 'c', '{"channel":"phone","items":[7]}'), (6, 'Dev Patel', 'west', DATE '2026-01-12', 510.00, 'widget', 'a', '{"channel":"web","items":[8,9]}'), (7, 'Carla Diaz', 'east', DATE '2026-01-20', 99.99, 'gizmo', 'b|c', '{"channel":"shop","items":[10]}'), (8, 'Dev Patel', 'west', DATE '2026-02-02', 510.00, 'widget', 'a', '{"channel":"web","items":[8,9]}'), (9, 'Eve Larsen', NULL, DATE '2026-02-03', 15.00, 'gadget', NULL, '{"channel":"web","items":[11]}'), (10, 'Alice Ng', 'north', DATE '2026-02-10', 220.00, 'gizmo', 'a|b|c', '{"channel":"phone","items":[12,13]}') ) t(order_id, customer, region, order_date, amount, product, tags, meta); ``` Then run the statement: ```sql CREATE TEMP TABLE result AS SELECT region, count(*) AS orders, sum(amount) AS total, round(avg(amount), 2) AS mean, max(order_date) AS latest FROM orders GROUP BY region ORDER BY total DESC; SELECT * FROM result; SELECT CASE WHEN ((SELECT count(*) = 5 AND sum(total) = 1900.74 AND max(total) FILTER (WHERE region = 'west') = 1020 AND max(orders) FILTER (WHERE region = 'north') = 3 FROM result)) THEN 'as expected' ELSE error('the groups do not total 1900.74 with west at 1020') END AS verdict; ``` It needs nothing installed beyond DuckDB itself. ## Variants - [Combine values into one cell per group](https://meridian.online/operations/summarise-by-group/combine-values-per-group): Join each group's values into one delimited string or one list. - [Summarise only rows that meet a condition](https://meridian.online/operations/summarise-by-group/conditional-aggregate): Compute an aggregate over just the rows of each group that satisfy a condition, alongside unfiltered aggregates in the same row. - Group rows and aggregate: Collapse the rows sharing a key into one row per key, with sums, counts, averages and other aggregates of the remaining columns. - Other summaries: Operators filed here that summarise in another way, such as run-length encoding or attaching an aggregate to every item. - [Median and percentiles per group](https://meridian.online/operations/summarise-by-group/percentiles-per-group): Compute the median, a quantile or several percentiles of each group, exactly or approximately. - Pick one value from the group: Return one value from each group: any, the first or last by an ordering, the nth or kth largest, or another column's value at the row where a key is largest or smallest. - Spread and statistical summaries: Compute standard deviation, variance, correlation, covariance, mode, weighted averages and other statistics per group. - [Summarise the whole table](https://meridian.online/operations/summarise-by-group/summarise-whole-table): Reduce the entire table to a single summary row, without grouping keys. ## What other tools call it Meridian's classification; an independent blind rating agreed on 86.2% of 312 rows (exact class, version 2). - Azure Data Factory: [`Aggregate`](https://learn.microsoft.com/en-us/azure/data-factory/data-flow-aggregate) (read 2026-09-27) - Azure Data Factory: [`Aggregate functions`](https://learn.microsoft.com/en-us/azure/data-factory/data-flow-aggregate-functions) (read 2026-09-27) - Azure Data Factory: [`Group by`](https://learn.microsoft.com/en-us/azure/data-factory/wrangling-functions) (read 2026-09-27) - Alteryx Designer: [`Calgary Cross Count`](https://help.alteryx.com/current/en/designer/tools/calgary/calgary-cross-count-tool.html) (read 2026-09-27) - Alteryx Designer: [`Count Records`](https://help.alteryx.com/current/en/designer/tools/transform/count-records-tool.html) (read 2026-09-27) - Alteryx Designer: [`Create Profile`](https://help.alteryx.com/current/en/designer/tools/behavior-analysis/create-profile-tool.html) (read 2026-09-27) - Alteryx Designer: [`Summarize`](https://help.alteryx.com/current/en/designer/tools/transform/summarize-tool.html) (read 2026-09-27) - Alteryx Designer: [`Summarize In-DB`](https://help.alteryx.com/current/en/designer/tools/in-database/summarize-in-db-tool.html) (read 2026-09-27) - Alteryx Designer: [`Weighted Average`](https://help.alteryx.com/current/en/designer/tools/transform/weighted-average-tool.html) (read 2026-09-27) - Bruin: [`Metrics`](https://getbruin.com/docs/bruin/core-concepts/semantic-layer.html) (read 2026-09-27) - Bruin: [`bruin.group_by(n)`](https://getbruin.com/docs/bruin/assets/templating/macros.html) (read 2026-09-27) - Apache DataFusion: [`AGGREGATE`](https://datafusion.apache.org/user-guide/sql/select.html) (read 2026-09-27) - Apache DataFusion: [`Aggregate (GROUP BY)`](https://datafusion.apache.org/user-guide/features.html) (read 2026-09-27) - Apache DataFusion: [`FILTER (WHERE ...)`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`GROUP BY ALL`](https://datafusion.apache.org/user-guide/sql/select.html) (read 2026-09-27) - Apache DataFusion: [`WITHIN GROUP (ORDER BY ...)`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`aggregate`](https://docs.rs/datafusion/latest/datafusion/dataframe/struct.DataFrame.html) (read 2026-09-27) - Apache DataFusion: [`any_value`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`approx_distinct`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`approx_median`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`approx_percentile_cont`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`approx_percentile_cont_with_weight`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`array_agg`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`avg`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`bit_and`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`bit_or`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`bit_xor`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`bool_and`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`bool_or`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`count`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`count`](https://docs.rs/datafusion/latest/datafusion/dataframe/struct.DataFrame.html) (read 2026-09-27) - Apache DataFusion: [`first_value`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`last_value`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`max`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`median`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`min`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`nth_value`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`percentile_cont`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`stddev`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`stddev_pop`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`string_agg`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`sum`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`var`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - Apache DataFusion: [`var_pop`](https://datafusion.apache.org/user-guide/sql/aggregate_functions.html) (read 2026-09-27) - dbt-utils: [`any_value`](https://docs.getdbt.com/reference/dbt-jinja-functions/cross-database-macros) (read 2026-09-27) - dbt-utils: [`bool_or`](https://docs.getdbt.com/reference/dbt-jinja-functions/cross-database-macros) (read 2026-09-27) - dbt-utils: [`group_by`](https://raw.githubusercontent.com/dbt-labs/dbt-utils/main/README.md) (read 2026-09-27) - dbt-utils: [`listagg`](https://docs.getdbt.com/reference/dbt-jinja-functions/cross-database-macros) (read 2026-09-27) - DuckDB: [`Aggregate Functions (family)`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`FILTER (clause)`](https://duckdb.org/docs/current/sql/query_syntax/filter) (read 2026-09-27) - DuckDB: [`GROUP BY (clause)`](https://duckdb.org/docs/current/sql/query_syntax/groupby) (read 2026-09-27) - DuckDB: [`any_value`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`approx_count_distinct`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`arbitrary`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`arg_max`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`arg_max_null`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`arg_max_nulls_last`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`arg_min`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`arg_min_null`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`arg_min_nulls_last`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`argmax`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`argmin`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`array_agg`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`avg`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`bit_and`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`bit_or`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`bit_xor`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`bitstring_agg`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`bool_and`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`bool_or`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`count`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`count_if`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`count_star`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`countif`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`favg`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`first`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`fsum`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`group_concat`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`kahan_sum`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`last`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`list`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`listagg`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`max`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`max_by`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`mean`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`min`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`min_by`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`product`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`sem`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`stddev`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`stddev_pop`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`stddev_samp`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`string_agg`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`sum`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`sum_no_overflow`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`sumkahan`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`var_pop`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`var_samp`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - DuckDB: [`variance`](https://duckdb.org/docs/current/sql/functions/aggregates) (read 2026-09-27) - Duckle: [`Approx Quantile`](https://github.com/slothflowlabs/duckle/blob/f85f8960edfb6efbf4cb89d58a7b32e16df0e867/website/docs/components.html) (read 2026-09-25) - Duckle: [`Array Aggregate`](https://github.com/slothflowlabs/duckle/blob/f85f8960edfb6efbf4cb89d58a7b32e16df0e867/website/docs/components.html) (read 2026-09-25) - Duckle: [`Collect List`](https://github.com/slothflowlabs/duckle/blob/f85f8960edfb6efbf4cb89d58a7b32e16df0e867/website/docs/components.html) (read 2026-09-25) - Duckle: [`Count Rows`](https://github.com/slothflowlabs/duckle/blob/f85f8960edfb6efbf4cb89d58a7b32e16df0e867/website/docs/components.html) (read 2026-09-25) - Duckle: [`Denormalize`](https://github.com/slothflowlabs/duckle/blob/f85f8960edfb6efbf4cb89d58a7b32e16df0e867/website/docs/components.html) (read 2026-09-25) - Duckle: [`Diff Summary`](https://github.com/slothflowlabs/duckle/blob/f85f8960edfb6efbf4cb89d58a7b32e16df0e867/frontend/src/workflow-ui/palette-data.ts) (read 2026-09-25) - Duckle: [`Group By`](https://github.com/slothflowlabs/duckle/blob/f85f8960edfb6efbf4cb89d58a7b32e16df0e867/website/docs/components.html) (read 2026-09-25) - EasyMorph: [`Aggregate`](https://help.easymorph.com/doku.php?id=transformations:aggregate) (read 2026-09-27) - EasyMorph: [`Concatenate text`](https://help.easymorph.com/doku.php?id=transformations:concatenatetext) (read 2026-09-27) - EasyMorph: [`Statistical aggregation`](https://help.easymorph.com/doku.php?id=transformations:statisticalaggregation) (read 2026-09-27) - AWS Glue: [`Aggregate`](https://docs.aws.amazon.com/glue/latest/dg/transforms-aggregate-fields.html) (read 2026-09-27) - Apache Hop: [`Group By`](https://hop.apache.org/manual/latest/pipeline/transforms/groupby.html) (read 2026-09-27) - Apache Hop: [`Memory Group By`](https://hop.apache.org/manual/latest/pipeline/transforms/memgroupby.html) (read 2026-09-27) - Ibis: [`Aggregate`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/relations.py) (read 2026-09-27) - Ibis: [`All`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Any`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`ApproxCountDistinct`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`ApproxMedian`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`ApproxMultiQuantile`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`ApproxQuantile`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Arbitrary`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`ArgMax`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`ArgMin`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`ArrayCollect`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`BitAnd`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`BitOr`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`BitXor`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Correlation`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Count`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`CountDistinct`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`CountDistinctStar`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`CountStar`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Covariance`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`First`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`GroupConcat`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Kurtosis`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Last`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Max`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Mean`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Median`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Min`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Mode`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`MultiQuantile`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Quantile`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`StandardDev`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Sum`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - Ibis: [`Variance`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/reductions.py) (read 2026-09-27) - KNIME Analytics Platform: [`DB GroupBy`](https://api.hub.knime.com/nodes/*YJIwMkiTMpJtVTUT?details=full) (read 2026-09-27) - KNIME Analytics Platform: [`GroupBy`](https://api.hub.knime.com/nodes/*5stmXk6zY_ORA4bC?details=full) (read 2026-09-27) - KNIME Analytics Platform: [`Row Aggregator`](https://api.hub.knime.com/nodes/*NtiMv8IfKOQIOILD?details=full) (read 2026-09-27) - OpenRefine: [`Join multi-valued cells…`](https://openrefine.org/docs/manual/cellediting#join-multi-valued-cells) (read 2026-09-27) - Pentaho Data Integration: [`Group By`](https://docs.pentaho.com/pdia-data-integration/9.3-data-integration/pdi-transformation-steps-reference-overview) (read 2026-09-27) - Pentaho Data Integration: [`Memory Group By`](https://docs.pentaho.com/pdia-data-integration/9.3-data-integration/pdi-transformation-steps-reference-overview) (read 2026-09-27) - Polars: [`DataFrame.count`](https://docs.pola.rs/api/python/stable/reference/dataframe/aggregation.html) (read 2026-09-27) - Polars: [`DataFrame.group_by`](https://docs.pola.rs/api/python/stable/reference/dataframe/modify_select.html) (read 2026-09-27) - Polars: [`DataFrame.max`](https://docs.pola.rs/api/python/stable/reference/dataframe/aggregation.html) (read 2026-09-27) - Polars: [`DataFrame.mean`](https://docs.pola.rs/api/python/stable/reference/dataframe/aggregation.html) (read 2026-09-27) - Polars: [`DataFrame.median`](https://docs.pola.rs/api/python/stable/reference/dataframe/aggregation.html) (read 2026-09-27) - Polars: [`DataFrame.min`](https://docs.pola.rs/api/python/stable/reference/dataframe/aggregation.html) (read 2026-09-27) - Polars: [`DataFrame.product`](https://docs.pola.rs/api/python/stable/reference/dataframe/aggregation.html) (read 2026-09-27) - Polars: [`DataFrame.quantile`](https://docs.pola.rs/api/python/stable/reference/dataframe/aggregation.html) (read 2026-09-27) - Polars: [`DataFrame.std`](https://docs.pola.rs/api/python/stable/reference/dataframe/aggregation.html) (read 2026-09-27) - Polars: [`DataFrame.sum`](https://docs.pola.rs/api/python/stable/reference/dataframe/aggregation.html) (read 2026-09-27) - Polars: [`DataFrame.var`](https://docs.pola.rs/api/python/stable/reference/dataframe/aggregation.html) (read 2026-09-27) - Polars: [`Expr aggregation expressions (group)`](https://docs.pola.rs/api/python/stable/reference/expressions/aggregation.html) (read 2026-09-27) - Polars: [`Expr computation: statistics (group)`](https://docs.pola.rs/api/python/stable/reference/expressions/computation.html) (read 2026-09-27) - Polars: [`Expr.rle`](https://docs.pola.rs/api/python/stable/reference/expressions/modify_select.html) (read 2026-09-27) - Polars: [`Expr.str: vertical concatenation (group)`](https://docs.pola.rs/api/python/stable/reference/expressions/string.html) (read 2026-09-27) - Polars: [`Functions: aggregation shortcuts (group)`](https://docs.pola.rs/api/python/stable/reference/expressions/functions.html) (read 2026-09-27) - Polars: [`GroupBy.agg`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`GroupBy.all`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`GroupBy.count`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`GroupBy.first`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`GroupBy.last`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`GroupBy.len`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`GroupBy.max`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`GroupBy.mean`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`GroupBy.median`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`GroupBy.min`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`GroupBy.n_unique`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`GroupBy.quantile`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`GroupBy.sum`](https://docs.pola.rs/api/python/stable/reference/dataframe/group_by.html) (read 2026-09-27) - Polars: [`SQL functions: Aggregate (group)`](https://docs.pola.rs/api/python/stable/reference/sql/functions/aggregate.html) (read 2026-09-27) - Polars: [`corr`](https://docs.pola.rs/api/python/stable/reference/expressions/functions.html) (read 2026-09-27) - Polars: [`cov`](https://docs.pola.rs/api/python/stable/reference/expressions/functions.html) (read 2026-09-27) - Power Query M: [`Table.AggregateTableColumn`](https://learn.microsoft.com/en-us/powerquery-m/table-functions#transformation) (read 2026-09-27) - Power Query M: [`Table.Group`](https://learn.microsoft.com/en-us/powerquery-m/table-functions#transformation) (read 2026-09-27) - RapidMiner Studio: [`Aggregate`](https://docs.rapidminer.com/latest/studio/operators/blending/table/grouping/aggregate.html) (read 2026-09-27) - RapidMiner Studio: [`Aggregate (In Database)`](https://docs.rapidminer.com/latest/studio/operators/extensions/In-Database%20Processing/indb_blending/indb_aggregate.html) (read 2026-09-27) - RapidMiner Studio: [`Aggregate Meta Data`](https://docs.rapidminer.com/latest/studio/operators/extensions/Text%20Processing/extraction/aggregate_meta_data.html) (read 2026-09-27) - RapidMiner Studio: [`Extract Aggregates`](https://docs.rapidminer.com/latest/studio/operators/modeling/time_series/feature_extraction/extract_std_descriptive_features.html) (read 2026-09-27) - RapidMiner Studio: [`Extract Mode`](https://docs.rapidminer.com/latest/studio/operators/modeling/time_series/feature_extraction/extract_mode.html) (read 2026-09-27) - SQLMesh: [`@GROUP_BY`](https://github.com/SQLMesh/sqlmesh/blob/23b237cea7218cc8f338b89c14f0957394a0003b/docs/concepts/macros/sqlmesh_macros.md) (read 2026-09-27) - Tableau Prep: [`Aggregate`](https://help.tableau.com/current/prep/en-us/prep_combine.htm) (read 2026-09-27) - Tableau Prep: [`Aggregate functions (group)`](https://help.tableau.com/current/prep/en-us/prep_function_reference.htm) (read 2026-09-27) - Talend: [`tAggregateRow`](https://help.qlik.com/talend/en-US/components/8.0/processing/processing-component) (read 2026-09-27) - Talend: [`tAggregateSortedRow`](https://help.qlik.com/talend/en-US/components/8.0/processing/processing-component) (read 2026-09-27) - Talend: [`tCombinedSQLAggregate`](https://help.qlik.com/talend/en-US/components/8.0/combinedsql/combinedsql-component) (read 2026-09-27) - Talend: [`tDenormalize`](https://help.qlik.com/talend/en-US/components/8.0/processing/processing-component) (read 2026-09-27) - Talend: [`tDenormalizeSortedRow`](https://help.qlik.com/talend/en-US/components/8.0/processing/processing-component) (read 2026-09-27) - Talend: [`tSQLTemplateAggregate`](https://help.qlik.com/talend/en-US/components/8.0/sqltemplate/sqltemplate-component) (read 2026-09-27) - Talend: [`tSurviveFields`](https://help.qlik.com/talend/en-US/components/8.0/deduplication/deduplication-component) (read 2026-09-27) - Trifacta: [`ANY Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`ANYIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`APPROXIMATEMEDIAN Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`APPROXIMATEPERCENTILE Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`APPROXIMATEQUARTILE Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`AVERAGE Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`AVERAGEIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`CORREL Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`COUNT Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`COUNTA Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`COUNTAIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`COUNTDISTINCT Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`COUNTDISTINCTIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`COUNTIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`COVAR Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`COVARSAMP Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`Group by`](https://help.alteryx.com/aac/en/trifacta-classic/reference/transformation-reference.html) (read 2026-09-27) - Trifacta: [`KTHLARGEST Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`KTHLARGESTIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`KTHLARGESTUNIQUE Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`KTHLARGESTUNIQUEIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`LIST Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`LISTIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`MAX Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`MAXIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`MEDIAN Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`MIN Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`MINIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`MODE Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`MODEIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`PERCENTILE Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`QUARTILE Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`STDEV Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`STDEVIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`STDEVSAMP Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`STDEVSAMPIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`SUM Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`SUMIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`UNIQUE Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`VAR Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`VARIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`VARSAMP Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - Trifacta: [`VARSAMPIF Function`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/aggregate-functions.html) (read 2026-09-27) - VisiData: [`addcol-aggr`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/pivot.py#L308) (read 2026-09-23) - VisiData: [`aggregate-col`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/aggregators.py#L409) (read 2026-09-23) - VisiData: [`aggregate-cols`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/aggregators.py#L411) (read 2026-09-23) - VisiData: [`flows`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/loaders/pcap.py#L409) (read 2026-09-23) - VisiData: [`freq-summary`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/freqtbl.py#L206) (read 2026-09-23) - VisiData: [`memo-aggregate`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/aggregators.py#L410) (read 2026-09-23)