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>
3.8 KiB
| layout | title | displayTitle | license |
|---|---|---|---|
| global | SHOW PARTITIONS | SHOW PARTITIONS | 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 SHOW PARTITIONS statement is used to list partitions of a table. An optional
partition spec may be specified to return the partitions matching the supplied
partition spec.
Syntax
{% highlight sql %} SHOW PARTITIONS table_identifier [ partition_spec ] {% endhighlight %}
Parameters
table_identifier-
Specifies a table name, which may be optionally qualified with a database name.
Syntax:[ database_name. ] table_name
partition_spec-
An optional parameter that specifies a comma separated list of key and value pairs
for partitions. When specified, the partitions that match the partition spec are returned.
Syntax:PARTITION ( partition_col_name [ = partition_col_val ] [ , ... ] )
Examples
{% highlight sql %} -- create a partitioned table and insert a few rows. USE salesdb; CREATE TABLE customer(id INT, name STRING) PARTITIONED BY (state STRING, city STRING); INSERT INTO customer PARTITION (state = 'CA', city = 'Fremont') VALUES (100, 'John'); INSERT INTO customer PARTITION (state = 'CA', city = 'San Jose') VALUES (200, 'Marry'); INSERT INTO customer PARTITION (state = 'AZ', city = 'Peoria') VALUES (300, 'Daniel');
-- Lists all partitions for table customer
SHOW PARTITIONS customer;
+----------------------+
| partition|
+----------------------+
| state=AZ/city=Peoria|
| state=CA/city=Fremont|
|state=CA/city=San Jose|
+----------------------+
-- Lists all partitions for the qualified table customer
SHOW PARTITIONS salesdb.customer;
+----------------------+
| partition|
+----------------------+
| state=AZ/city=Peoria|
| state=CA/city=Fremont|
|state=CA/city=San Jose|
+----------------------+
-- Specify a full partition spec to list specific partition SHOW PARTITIONS customer PARTITION (state = 'CA', city = 'Fremont'); +---------------------+ | partition| +---------------------+ |state=CA/city=Fremont| +---------------------+
-- Specify a partial partition spec to list the specific partitions SHOW PARTITIONS customer PARTITION (state = 'CA'); +----------------------+ | partition| +----------------------+ | state=CA/city=Fremont| |state=CA/city=San Jose| +----------------------+
-- Specify a partial spec to list specific partition SHOW PARTITIONS customer PARTITION (city = 'San Jose'); +----------------------+ | partition| +----------------------+ |state=CA/city=San Jose| +----------------------+ {% endhighlight %}