179289f0bf
### 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>
3.2 KiB
3.2 KiB
| layout | title | displayTitle | license |
|---|---|---|---|
| global | CREATE TABLE LIKE | CREATE TABLE LIKE | 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 CREATE TABLE statement defines a new table using the definition/metadata of an existing table or view.
Syntax
{% highlight sql %} CREATE TABLE [IF NOT EXISTS] table_identifier LIKE source_table_identifier USING data_source [ ROW FORMAT row_format ] [ STORED AS file_format ] [ TBLPROPERTIES ( key1=val1, key2=val2, ... ) ] [ LOCATION path ] {% endhighlight %}
Parameters
table_identifier-
Specifies a table name, which may be optionally qualified with a database name.
Syntax: [ TBLPROPERTIES ( key1=val1, key2=val2, ... ) ][ database_name. ] table_name
USING data_source- Data Source is the input format used to create the table. Data source can be CSV, TXT, ORC, JDBC, PARQUET, etc.
ROW FORMAT- SERDE is used to specify a custom SerDe or the DELIMITED clause in order to use the native SerDe.
STORED AS- File format for table storage, could be TEXTFILE, ORC, PARQUET,etc.
TBLPROPERTIES- Table properties that have to be set are specified, such as `created.by.user`, `owner`, etc.
LOCATION- Path to the directory where table data is stored,Path to the directory where table data is stored, which could be a path on distributed storage like HDFS, etc. Location to create an external table.
Examples
{% highlight sql %} -- Create table using an existing table CREATE TABLE Student_Dupli like Student;
-- Create table like using a data source CREATE TABLE Student_Dupli like Student USING CSV;
-- Table is created as external table at the location specified CREATE TABLE Student_Dupli like Student location '/root1/home';
-- Create table like using a rowformat CREATE TABLE Student_Dupli like Student ROW FORMAT DELIMITED FIELDS TERMINATED BY ',' STORED AS TEXTFILE TBLPROPERTIES ('owner'='xxxx'); {% endhighlight %}