spark-instrumented-optimizer/docs/sql-ref-syntax-qry-select-distribute-by.md

---
layout: global
title: DISTRIBUTE BY Clause
displayTitle: DISTRIBUTE BY Clause
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  this work for additional information regarding copyright ownership.
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---
The <code>DISTRIBUTE BY</code> clause is used to repartition the data based
on the input expressions. Unlike the [CLUSTER BY](sql-ref-syntax-qry-select-clusterby.html)
clause, this does not sort the data within each partition.

### Syntax
{% highlight sql %}
DISTRIBUTE BY { expression [ , ... ] }
{% endhighlight %}

### Parameters
<dl>
  <dt><code><em>expression</em></code></dt>
  <dd>
    Specifies combination of one or more values, operators and SQL functions that results in a value.
  </dd>
</dl>

### Examples
{% highlight sql %}
CREATE TABLE person (name STRING, age INT);
INSERT INTO person VALUES
    ('Zen Hui', 25),
    ('Anil B', 18),
    ('Shone S', 16),
    ('Mike A', 25),
    ('John A', 18),
    ('Jack N', 16);

-- Reduce the number of shuffle partitions to 2 to illustrate the behavior of `DISTRIBUTE BY`.
-- It's easier to see the clustering and sorting behavior with less number of partitions.
SET spark.sql.shuffle.partitions = 2;

-- Select the rows with no ordering. Please note that without any sort directive, the result
-- of the query is not deterministic. It's included here to just contrast it with the
-- behavior of `DISTRIBUTE BY`. The query below produces rows where age columns are not
-- clustered together.
SELECT age, name FROM person;

  +---+-------+
  |age|name   |
  +---+-------+
  |16 |Shone S|
  |25 |Zen Hui|
  |16 |Jack N |
  |25 |Mike A |
  |18 |John A |
  |18 |Anil B |
  +---+-------+

-- Produces rows clustered by age. Persons with same age are clustered together.
-- Unlike `CLUSTER BY` clause, the rows are not sorted within a partition.
SELECT age, name FROM person DISTRIBUTE BY age;

  +---+-------+
  |age|name   |
  +---+-------+
  |25 |Zen Hui|
  |25 |Mike A |
  |18 |John A |
  |18 |Anil B |
  |16 |Shone S|
  |16 |Jack N |
  +---+-------+
{% endhighlight %}

### Related Clauses
- [SELECT Main](sql-ref-syntax-qry-select.html)
- [WHERE Clause](sql-ref-syntax-qry-select-where.html)
- [GROUP BY Clause](sql-ref-syntax-qry-select-groupby.html)
- [HAVING Clause](sql-ref-syntax-qry-select-having.html)
- [ORDER BY Clause](sql-ref-syntax-qry-select-orderby.html)
- [SORT BY Clause](sql-ref-syntax-qry-select-sortby.html)
- [CLUSTER BY Clause](sql-ref-syntax-qry-select-clusterby.html)
- [LIMIT Clause](sql-ref-syntax-qry-select-limit.html)