spark-instrumented-optimizer/docs/sql-data-sources-text.md
itholic 7c32415669 [SPARK-35523] Fix the default value in Data Source Options page
### What changes were proposed in this pull request?

This PR proposes fix the default value in Data Source Option page based on the Scala documentation.

### Why are the changes needed?

Some of the existing default value in Data Source Option page follow the Python documentation, which has `None` as the default value for all options.

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

Yes, the default value in the Data Source Option page is fixed (from `None` to proper default value)

- Before
<img width="361" alt="Screen Shot 2021-06-02 at 6 31 12 PM" src="https://user-images.githubusercontent.com/44108233/120456594-b8719f00-c3d0-11eb-9778-071ab2ba9f45.png">

- After
<img width="562" alt="Screen Shot 2021-06-02 at 6 32 47 PM" src="https://user-images.githubusercontent.com/44108233/120456844-f1117880-c3d0-11eb-9c7c-9dcd66776444.png">

### How was this patch tested?

Manually built the docs and checked one by one.

Closes #32745 from itholic/SPARK-35523.

Lead-authored-by: itholic <haejoon.lee@databricks.com>
Co-authored-by: Haejoon Lee <44108233+itholic@users.noreply.github.com>
Signed-off-by: Hyukjin Kwon <gurwls223@apache.org>
2021-06-04 14:08:13 +09:00

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Markdown

---
layout: global
title: Text Files
displayTitle: Text Files
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.
---
Spark SQL provides `spark.read().text("file_name")` to read a file or directory of text files into a Spark DataFrame, and `dataframe.write().text("path")` to write to a text file. When reading a text file, each line becomes each row that has string "value" column by default. The line separator can be changed as shown in the example below. The `option()` function can be used to customize the behavior of reading or writing, such as controlling behavior of the line separator, compression, and so on.
<div class="codetabs">
<div data-lang="scala" markdown="1">
{% include_example text_dataset scala/org/apache/spark/examples/sql/SQLDataSourceExample.scala %}
</div>
<div data-lang="java" markdown="1">
{% include_example text_dataset java/org/apache/spark/examples/sql/JavaSQLDataSourceExample.java %}
</div>
<div data-lang="python" markdown="1">
{% include_example text_dataset python/sql/datasource.py %}
</div>
</div>
## Data Source Option
Data source options of text can be set via:
* the `.option`/`.options` methods of
* `DataFrameReader`
* `DataFrameWriter`
* `DataStreamReader`
* `DataStreamWriter`
* `OPTIONS` clause at [CREATE TABLE USING DATA_SOURCE](sql-ref-syntax-ddl-create-table-datasource.html)
<table class="table">
<tr><th><b>Property Name</b></th><th><b>Default</b></th><th><b>Meaning</b></th><th><b>Scope</b></th></tr>
<tr>
<td><code>wholetext</code></td>
<td><code>false</code></td>
<td>If true, read each file from input path(s) as a single row.</td>
<td>read</td>
</tr>
<tr>
<td><code>lineSep</code></td>
<td><code>\r</code>, <code>\r\n</code>, <code>\n</code> (for reading), <code>\n</code> (for writing)</td>
<td>Defines the line separator that should be used for reading or writing.</td>
<td>read/write</td>
</tr>
<tr>
<td><code>compression</code></td>
<td>(none)</td>
<td>Compression codec to use when saving to file. This can be one of the known case-insensitive shorten names (none, bzip2, gzip, lz4, snappy and deflate).</td>
<td>write</td>
</tr>
</table>
Other generic options can be found in <a href="https://spark.apache.org/docs/latest/sql-data-sources-generic-options.html"> Generic File Source Options</a>.