babefdee1c
### What changes were proposed in this pull request? Standardize sql reference ### Why are the changes needed? To have consistent docs ### Does this PR introduce any user-facing change? Yes ### How was this patch tested? Tested using jykyll build --serve Closes #26721 from huaxingao/spark-30085. Authored-by: Huaxin Gao <huaxing@us.ibm.com> Signed-off-by: Sean Owen <sean.owen@databricks.com>
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| layout | title | displayTitle | license |
|---|---|---|---|
| global | TRUNCATE TABLE | TRUNCATE TABLE | 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 TRUNCATE TABLE statement removes all the rows from a table or partition(s). The table must not be a view
or an external/temporary table. In order to truncate multiple partitions at once, the user can specify the partitions
in partition_spec. If no partition_spec is specified it will remove all partitions in the table.
Syntax
{% highlight sql %} TRUNCATE TABLE 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.
Syntax:PARTITION ( partition_col_name = partition_col_val [ , ... ] )
Examples
{% highlight sql %}
--Create table Student with partition CREATE TABLE Student ( name String, rollno INT) PARTITIONED BY (age int);
SELECT * from Student; +-------+---------+------+--+ | name | rollno | age | +-------+---------+------+--+ | ABC | 1 | 10 | | DEF | 2 | 10 | | XYZ | 3 | 12 | +-------+---------+------+--+
-- Removes all rows from the table in the partition specified TRUNCATE TABLE Student partition(age=10);
--After truncate execution, records belonging to partition age=10 are removed SELECT * from Student; +-------+---------+------+--+ | name | rollno | age | +-------+---------+------+--+ | XYZ | 3 | 12 | +-------+---------+------+--+
-- Removes all rows from the table from all partitions TRUNCATE TABLE Student;
SELECT * from Student; +-------+---------+------+--+ | name | rollno | age | +-------+---------+------+--+ +-------+---------+------+--+ No rows selected
{% endhighlight %}