versioned_docs/version-1.2/sql-manual/sql-functions/aggregate-functions/grouping.md

---
{
    "title": "GROUPING",
    "language": "en"
}
---

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## GROUPING

### Name

GROUPING

### Description

Indicates whether a specified column expression in a `GROUP BY` list is aggregated or not. `GROUPING` returns 1 for aggregated or 0 for not aggregated in the result set. `GROUPING` can be used only in the `SELECT <select> list`, `HAVING`, and `ORDER BY` clauses when `GROUP BY` is specified.

`GROUPING` is used to distinguish the null values that are returned by `ROLLUP`, `CUBE` or `GROUPING SETS` from standard null values. The `NULL` returned as the result of a `ROLLUP`, `CUBE` or `GROUPING SETS` operation is a special use of `NULL`. This acts as a column placeholder in the result set and means all.

```sql
GROUPING( <column_expression> )
```

`<column_expression>`
Is a column or an expression that contains a column in a `GROUP BY` clause.

Return Types: BIGINT

### Example

The following example groups `camp` and aggregates `occupation` amounts in the database. The `GROUPING` function is applied to the `camp` column.

```sql
CREATE TABLE `roles` (
  role_id       INT,
  occupation    VARCHAR(32),
  camp          VARCHAR(32),
  register_time DATE
)
UNIQUE KEY(role_id)
DISTRIBUTED BY HASH(role_id) BUCKETS 1
PROPERTIES (
  "replication_allocation" = "tag.location.default: 1"
);

INSERT INTO `roles` VALUES
(0, 'who am I', NULL, NULL),
(1, 'mage', 'alliance', '2018-12-03 16:11:28'),
(2, 'paladin', 'alliance', '2018-11-30 16:11:28'),
(3, 'rogue', 'horde', '2018-12-01 16:11:28'),
(4, 'priest', 'alliance', '2018-12-02 16:11:28'),
(5, 'shaman', 'horde', NULL),
(6, 'warrior', 'alliance', NULL),
(7, 'warlock', 'horde', '2018-12-04 16:11:28'),
(8, 'hunter', 'horde', NULL);

SELECT 
  camp, 
  COUNT(occupation) AS 'occ_cnt',
  GROUPING(camp)    AS 'grouping'
FROM
   `roles`
GROUP BY
  ROLLUP(camp); -- CUBE(camp) and GROUPING SETS((camp)) also can work;
```

The result set shows two null value under `camp`. The first NULL is in the summary row added by the `ROLLUP` operation. The summary row shows the occupation counts for all `camp` groups and is indicated by 1 in the Grouping column. The second NULL represents the group of null values from this column in the table.

Here is the result set.

```log
+----------+---------+----------+
| camp     | occ_cnt | grouping |
+----------+---------+----------+
| NULL     |       9 |        1 |
| NULL     |       1 |        0 |
| alliance |       4 |        0 |
| horde    |       4 |        0 |
+----------+---------+----------+
4 rows in set (0.01 sec)
```

### Keywords

GROUPING

### Best Practice

See also [GROUPING_ID](./grouping_id.md)