---
layout: global
title: UNCACHE TABLE
displayTitle: UNCACHE TABLE
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**This page is under construction**

---
layout: global
title: UNCACHE TABLE
displayTitle: UNCACHE TABLE
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
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---

### Description
`UNCACHE TABLE` removes the entries and associated data from the in-memory and/or on-disk cache for a given table. The
underlying entries should already have been brought to cache by previous `CACHE TABLE` operation. `UNCACHE TABLE` on a non-existent table throws Exception if `IF EXISTS` is not specified.
### Syntax
{% highlight sql %}
UNCACHE TABLE [ IF EXISTS ] table_name
{% endhighlight %}
### Parameters
<dl>
 <dt><code><em>table_name</em></code></dt>
 <dd>The name of the table to be uncached.</dd>
</dl>
### Examples
{% highlight sql %}
UNCACHE TABLE t1;
{% endhighlight %}
### Related Statements
 * [CACHE TABLE](sql-ref-syntax-aux-cache-cache-table.html)
 * [CLEAR CACHE](sql-ref-syntax-aux-cache-clear-cache.html)

Document UNCACHE TABLE statement in SQL Reference
[SPARK-28830][DOC][SQL] Document UNCACHE TABLE statement in SQL Reference

### What changes were proposed in this pull request?
Document UNCACHE TABLE statement in SQL Reference
### Why are the changes needed?
To complete SQL Reference

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

After change:

![image](https://user-images.githubusercontent.com/13592258/64299133-e04a7f00-cf2c-11e9-8f39-9b288e46c995.png)

### How was this patch tested?
Tested using jykyll build --serve

Closes #25540 from huaxingao/spark-28830.

Lead-authored-by: Huaxin Gao <b1011540267ee7fe5a02243ad09c007ca1860809@us.ibm.com>
Co-authored-by: Xiao Li <905db6c57c9ba2de5402239d136139da9b5d0058@gmail.com>
Signed-off-by: Xiao Li <905db6c57c9ba2de5402239d136139da9b5d0058@gmail.com>
