spark-instrumented-optimizer/docs/sql-ref-syntax-qry-select-limit.md
Takeshi Yamamuro ffec7a1964 [SQL][DOCS][MINOR] Fix typos and wrong phrases in docs
### What changes were proposed in this pull request?

This PR intends to fix typos and phrases in the `/docs` directory. To find them, I run the Intellij typo checker.

### Why are the changes needed?

For better documents.

### Does this PR introduce any user-facing change?

No.

### How was this patch tested?

N/A

Closes #27819 from maropu/TypoFix-20200306.

Authored-by: Takeshi Yamamuro <yamamuro@apache.org>
Signed-off-by: Gengliang Wang <gengliang.wang@databricks.com>
2020-03-05 16:54:59 -08:00

3 KiB

layout title displayTitle license
global LIMIT Clause LIMIT Clause Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

The LIMIT clause is used to constrain the number of rows returned by the SELECT statement. In general, this clause is used in conjunction with ORDER BY to ensure that the results are deterministic.

Syntax

{% highlight sql %} LIMIT { ALL | integer_expression } {% endhighlight %}

Parameters

ALL
If specified, the query returns all the rows. In other words, no limit is applied if this option is specified.
integer_expression
Specifies an expression that returns an integer.

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);

-- Select the first two rows. SELECT name, age FROM person ORDER BY name LIMIT 2;

+------+---+ |name |age| +------+---+ |Anil B|18 | |Jack N|16 | +------+---+

-- Specifying ALL option on LIMIT returns all the rows. SELECT name, age FROM person ORDER BY name LIMIT ALL;

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

-- A function expression as an input to limit. SELECT name, age FROM person ORDER BY name LIMIT length('SPARK')

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