485145326a
### What changes were proposed in this pull request?
This PR intends to fix typos in the sub-modules:
* `bin`
* `core`
* `docs`
* `external`
* `mllib`
* `repl`
* `pom.xml`
Split per srowen https://github.com/apache/spark/pull/30323#issuecomment-728981618
NOTE: The misspellings have been reported at 706a726f87 (commitcomment-44064356)
### Why are the changes needed?
Misspelled words make it harder to read / understand content.
### Does this PR introduce _any_ user-facing change?
There are various fixes to documentation, etc...
### How was this patch tested?
No testing was performed
Closes #30530 from jsoref/spelling-bin-core-docs-external-mllib-repl.
Authored-by: Josh Soref <jsoref@users.noreply.github.com>
Signed-off-by: Takeshi Yamamuro <yamamuro@apache.org>
149 lines
4.3 KiB
Markdown
149 lines
4.3 KiB
Markdown
---
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layout: global
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title: ORDER BY Clause
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displayTitle: ORDER BY Clause
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license: |
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Licensed to the Apache Software Foundation (ASF) under one or more
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contributor license agreements. See the NOTICE file distributed with
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this work for additional information regarding copyright ownership.
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The ASF licenses this file to You under the Apache License, Version 2.0
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(the "License"); you may not use this file except in compliance with
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the License. You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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---
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### Description
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The `ORDER BY` clause is used to return the result rows in a sorted manner
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in the user specified order. Unlike the [SORT BY](sql-ref-syntax-qry-select-sortby.html)
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clause, this clause guarantees a total order in the output.
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### Syntax
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```sql
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ORDER BY { expression [ sort_direction | nulls_sort_order ] [ , ... ] }
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```
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### Parameters
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* **ORDER BY**
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Specifies a comma-separated list of expressions along with optional parameters `sort_direction`
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and `nulls_sort_order` which are used to sort the rows.
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* **sort_direction**
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Optionally specifies whether to sort the rows in ascending or descending
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order. The valid values for the sort direction are `ASC` for ascending
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and `DESC` for descending. If sort direction is not explicitly specified, then by default
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rows are sorted ascending.
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**Syntax:** [ ASC `|` DESC ]
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* **nulls_sort_order**
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Optionally specifies whether NULL values are returned before/after non-NULL values. If
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`null_sort_order` is not specified, then NULLs sort first if sort order is
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`ASC` and NULLS sort last if sort order is `DESC`.
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1. If `NULLS FIRST` is specified, then NULL values are returned first
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regardless of the sort order.
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2. If `NULLS LAST` is specified, then NULL values are returned last regardless of
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the sort order.
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**Syntax:** `[ NULLS { FIRST | LAST } ]`
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### Examples
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```sql
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CREATE TABLE person (id INT, name STRING, age INT);
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INSERT INTO person VALUES
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(100, 'John', 30),
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(200, 'Mary', NULL),
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(300, 'Mike', 80),
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(400, 'Jerry', NULL),
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(500, 'Dan', 50);
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-- Sort rows by age. By default rows are sorted in ascending manner with NULL FIRST.
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SELECT name, age FROM person ORDER BY age;
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+-----+----+
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| name| age|
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+-----+----+
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|Jerry|null|
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| Mary|null|
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| John| 30|
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| Dan| 50|
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| Mike| 80|
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+-----+----+
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-- Sort rows in ascending manner keeping null values to be last.
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SELECT name, age FROM person ORDER BY age NULLS LAST;
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+-----+----+
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| name| age|
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+-----+----+
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| John| 30|
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| Dan| 50|
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| Mike| 80|
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| Mary|null|
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|Jerry|null|
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+-----+----+
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-- Sort rows by age in descending manner, which defaults to NULL LAST.
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SELECT name, age FROM person ORDER BY age DESC;
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+-----+----+
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| name| age|
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+-----+----+
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| Mike| 80|
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| Dan| 50|
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| John| 30|
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|Jerry|null|
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| Mary|null|
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+-----+----+
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-- Sort rows in ascending manner keeping null values to be first.
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SELECT name, age FROM person ORDER BY age DESC NULLS FIRST;
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+-----+----+
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| name| age|
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+-----+----+
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|Jerry|null|
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| Mary|null|
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| Mike| 80|
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| Dan| 50|
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| John| 30|
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+-----+----+
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-- Sort rows based on more than one column with each column having different
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-- sort direction.
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SELECT * FROM person ORDER BY name ASC, age DESC;
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+---+-----+----+
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| id| name| age|
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+---+-----+----+
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|500| Dan| 50|
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|400|Jerry|null|
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|100| John| 30|
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|200| Mary|null|
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|300| Mike| 80|
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+---+-----+----+
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```
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### Related Statements
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* [SELECT Main](sql-ref-syntax-qry-select.html)
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* [WHERE Clause](sql-ref-syntax-qry-select-where.html)
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* [GROUP BY Clause](sql-ref-syntax-qry-select-groupby.html)
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* [HAVING Clause](sql-ref-syntax-qry-select-having.html)
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* [SORT BY Clause](sql-ref-syntax-qry-select-sortby.html)
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* [CLUSTER BY Clause](sql-ref-syntax-qry-select-clusterby.html)
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* [DISTRIBUTE BY Clause](sql-ref-syntax-qry-select-distribute-by.html)
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* [LIMIT Clause](sql-ref-syntax-qry-select-limit.html)
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* [CASE Clause](sql-ref-syntax-qry-select-case.html)
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* [PIVOT Clause](sql-ref-syntax-qry-select-pivot.html)
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* [LATERAL VIEW Clause](sql-ref-syntax-qry-select-lateral-view.html)
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