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spark-instrumented-optimizer/docs/sql-ref-syntax-dml-insert-overwrite-directory-hive.md
Takeshi Yamamuro 179289f0bf [SPARK-31383][SQL][DOC] Clean up the SQL documents in docs/sql-ref* 
### What changes were proposed in this pull request?

This PR intends to clean up the SQL documents in `doc/sql-ref*`.
Main changes are as follows;

 - Fixes wrong syntaxes and capitalize sub-titles
 - Adds some DDL queries in `Examples` so that users can run examples there
 - Makes query output in `Examples` follows the `Dataset.showString` (right-aligned) format
 - Adds/Removes spaces, Indents, or blank lines to follow the format below;

```
---
license...
---

### Description

Writes what's the syntax is.

### Syntax

{% highlight sql %}
SELECT...
    WHERE... // 4 indents after the second line
    ...
{% endhighlight %}

### Parameters

<dl>

  <dt><code><em>Param Name</em></code></dt>
  <dd>
    Param Description
  </dd>
  ...
</dl>

### Examples

{% highlight sql %}
-- It is better that users are able to execute example queries here.
-- So, we prepare test data in the first section if possible.
CREATE TABLE t (key STRING, value DOUBLE);
INSERT INTO t VALUES
    ('a', 1.0), ('a', 2.0), ('b', 3.0), ('c', 4.0);

-- query output has 2 indents and it follows the `Dataset.showString`
-- format (right-aligned).
SELECT * FROM t;
  +---+-----+
  |key|value|
  +---+-----+
  |  a|  1.0|
  |  a|  2.0|
  |  b|  3.0|
  |  c|  4.0|
  +---+-----+

-- Query statements after the second line have 4 indents.
SELECT key, SUM(value)
    FROM t
    GROUP BY key;
  +---+----------+
  |key|sum(value)|
  +---+----------+
  |  c|       4.0|
  |  b|       3.0|
  |  a|       3.0|
  +---+----------+
...
{% endhighlight %}

### Related Statements

 * [XXX](xxx.html)
 * ...
```

### Why are the changes needed?

The most changes of this PR are pretty minor, but I think the consistent formats/rules to write documents are important for long-term maintenance in our community

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

Yes.

### How was this patch tested?

Manually checked.

Closes #28151 from maropu/MakeRightAligned.

Authored-by: Takeshi Yamamuro <yamamuro@apache.org>
Signed-off-by: Sean Owen <srowen@gmail.com>
2020-04-12 23:40:36 -05:00

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layout title displayTitle license
global INSERT OVERWRITE DIRECTORY with Hive format INSERT OVERWRITE DIRECTORY with Hive format 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.

Description

The INSERT OVERWRITE DIRECTORY with Hive format overwrites the existing data in the directory with the new values using Hive SerDe. Hive support must be enabled to use this command. The inserted rows can be specified by value expressions or result from a query.

Syntax

{% highlight sql %} INSERT OVERWRITE [ LOCAL ] DIRECTORY directory_path [ ROW FORMAT row_format ] [ STORED AS file_format ] { { VALUES ( { value | NULL } [ , ... ] ) [ , ( ... ) ] } | query } {% endhighlight %}

Parameters

directory_path
Specifies the destination directory. The LOCAL keyword is used to specify that the directory is on the local file system.
row_format
Specifies the row format for this insert. Valid options are SERDE clause and DELIMITED clause. SERDE clause can be used to specify a custom SerDe for this insert. Alternatively, DELIMITED clause can be used to specify the native SerDe and state the delimiter, escape character, null character, and so on.
file_format
Specifies the file format for this insert. Valid options are TEXTFILE, SEQUENCEFILE, RCFILE, ORC, PARQUET, and AVRO. You can also specify your own input and output format using INPUTFORMAT and OUTPUTFORMAT. ROW FORMAT SERDE can only be used with TEXTFILE, SEQUENCEFILE, or RCFILE, while ROW FORMAT DELIMITED can only be used with TEXTFILE.
VALUES ( { value | NULL } [ , ... ] ) [ , ( ... ) ]
Specifies the values to be inserted. Either an explicitly specified value or a NULL can be inserted. A comma must be used to separate each value in the clause. More than one set of values can be specified to insert multiple rows.
query
A query that produces the rows to be inserted. It can be in one of following formats:
  • a SELECT statement
  • a TABLE statement
  • a FROM statement

Examples

{% highlight sql %} INSERT OVERWRITE LOCAL DIRECTORY '/tmp/destination' STORED AS orc SELECT * FROM test_table;

INSERT OVERWRITE LOCAL DIRECTORY '/tmp/destination' ROW FORMAT DELIMITED FIELDS TERMINATED BY ',' SELECT * FROM test_table; {% endhighlight %}

Related Statements