spark-instrumented-optimizer/docs/sql-ref-syntax-qry-select-file.md
Takeshi Yamamuro c2bea045e3 [SPARK-33264][SQL][DOCS] Add a dedicated page for SQL-on-file in SQL documents
### What changes were proposed in this pull request?

This PR intends to add a dedicated page for SQL-on-file in SQL documents.
This comes from the comment: https://github.com/apache/spark/pull/30095/files#r508965149

### Why are the changes needed?

For better documentations.

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

<img width="544" alt="Screen Shot 2020-10-28 at 9 56 59" src="https://user-images.githubusercontent.com/692303/97378051-c1fbcb80-1904-11eb-86c0-a88c5269d41c.png">

### How was this patch tested?

N/A

Closes #30165 from maropu/DocForFile.

Authored-by: Takeshi Yamamuro <yamamuro@apache.org>
Signed-off-by: Takeshi Yamamuro <yamamuro@apache.org>
2020-10-28 11:21:35 +09:00

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---
layout: global
title: File
displayTitle: File
license: |
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
You can query a file with a specified format directly with SQL.
### Syntax
```sql
file_format.`file_path`
```
### Parameters
* **file_format**
Specifies a file format for a given file path, could be TEXTFILE, ORC, PARQUET, etc.
* **file_path**
Specifies a file path with a given format.
### Examples
```sql
-- PARQUET file
SELECT * FROM parquet.`examples/src/main/resources/users.parquet`;
+------+--------------+----------------+
| name|favorite_color|favorite_numbers|
+------+--------------+----------------+
|Alyssa| null| [3, 9, 15, 20]|
| Ben| red| []|
+------+--------------+----------------+
-- ORC file
SELECT * FROM orc.`examples/src/main/resources/users.orc`;
+------+--------------+----------------+
| name|favorite_color|favorite_numbers|
+------+--------------+----------------+
|Alyssa| null| [3, 9, 15, 20]|
| Ben| red| []|
+------+--------------+----------------+
-- JSON file
SELECT * FROM json.`examples/src/main/resources/people.json`;
+----+-------+
| age| name|
+----+-------+
|null|Michael|
| 30| Andy|
| 19| Justin|
+----+-------+
```
### Related Statements
* [SELECT](sql-ref-syntax-qry-select.html)