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

---
layout: global
title: ORDER BY Clause
displayTitle: ORDER BY Clause
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  this work for additional information regarding copyright ownership.
  The ASF licenses this file to You under the Apache License, Version 2.0
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---

### Description

The `ORDER BY` clause is used to return the result rows in a sorted manner
in the user specified order. Unlike the [SORT BY](sql-ref-syntax-qry-select-sortby.html)
clause, this clause guarantees a total order in the output.

### Syntax

```sql
ORDER BY { expression [ sort_direction | nulls_sort_oder ] [ , ... ] }
```

### Parameters

* **ORDER BY**

    Specifies a comma-separated list of expressions along with optional parameters `sort_direction`
    and `nulls_sort_order` which are used to sort the rows.

* **sort_direction**

    Optionally specifies whether to sort the rows in ascending or descending
    order. The valid values for the sort direction are `ASC` for ascending
    and `DESC` for descending. If sort direction is not explicitly specified, then by default
    rows are sorted ascending.

    **Syntax:** [ ASC `|` DESC ]

* **nulls_sort_order**

    Optionally specifies whether NULL values are returned before/after non-NULL values. If
    `null_sort_order` is not specified, then NULLs sort first if sort order is
    `ASC` and NULLS sort last if sort order is `DESC`.

    1. If `NULLS FIRST` is specified, then NULL values are returned first
       regardless of the sort order.
    2. If `NULLS LAST` is specified, then NULL values are returned last regardless of
       the sort order.

    **Syntax:** `[ NULLS { FIRST | LAST } ]`

### Examples

```sql
CREATE TABLE person (id INT, name STRING, age INT);
INSERT INTO person VALUES
    (100, 'John', 30),
    (200, 'Mary', NULL),
    (300, 'Mike', 80),
    (400, 'Jerry', NULL),
    (500, 'Dan',  50);

-- Sort rows by age. By default rows are sorted in ascending manner with NULL FIRST.
SELECT name, age FROM person ORDER BY age;
+-----+----+
| name| age|
+-----+----+
|Jerry|null|
| Mary|null|
| John|  30|
|  Dan|  50|
| Mike|  80|
+-----+----+

-- Sort rows in ascending manner keeping null values to be last.
SELECT name, age FROM person ORDER BY age NULLS LAST;
+-----+----+
| name| age|
+-----+----+
| John|  30|
|  Dan|  50|
| Mike|  80|
| Mary|null|
|Jerry|null|
+-----+----+

-- Sort rows by age in descending manner, which defaults to NULL LAST.
SELECT name, age FROM person ORDER BY age DESC;
+-----+----+
| name| age|
+-----+----+
| Mike|  80|
|  Dan|  50|
| John|  30|
|Jerry|null|
| Mary|null|
+-----+----+

-- Sort rows in ascending manner keeping null values to be first.
SELECT name, age FROM person ORDER BY age DESC NULLS FIRST;
+-----+----+
| name| age|
+-----+----+
|Jerry|null|
| Mary|null|
| Mike|  80|
|  Dan|  50|
| John|  30|
+-----+----+

-- Sort rows based on more than one column with each column having different
-- sort direction.
SELECT * FROM person ORDER BY name ASC, age DESC;
+---+-----+----+
| id| name| age|
+---+-----+----+
|500|  Dan|  50|
|400|Jerry|null|
|100| John|  30|
|200| Mary|null|
|300| Mike|  80|
+---+-----+----+
```

### Related Statements

* [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)
* [SORT BY Clause](sql-ref-syntax-qry-select-sortby.html)
* [CLUSTER BY Clause](sql-ref-syntax-qry-select-clusterby.html)
* [DISTRIBUTE BY Clause](sql-ref-syntax-qry-select-distribute-by.html)
* [LIMIT Clause](sql-ref-syntax-qry-select-limit.html)