a75dc80a76
### What changes were proposed in this pull request? Remove the unneeded embedded inline HTML markup by using the basic markdown syntax. Please see #28414 ### Why are the changes needed? Make the doc cleaner and easily editable by MD editors. ### Does this PR introduce _any_ user-facing change? No ### How was this patch tested? Manually build and check Closes #28451 from huaxingao/html_cleanup. Authored-by: Huaxin Gao <huaxing@us.ibm.com> Signed-off-by: Sean Owen <srowen@gmail.com>
89 lines
2.5 KiB
Markdown
89 lines
2.5 KiB
Markdown
---
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layout: global
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title: TRUNCATE TABLE
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displayTitle: TRUNCATE TABLE
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license: |
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Licensed to the Apache Software Foundation (ASF) under one or more
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contributor license agreements. See the NOTICE file distributed with
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this work for additional information regarding copyright ownership.
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The ASF licenses this file to You under the Apache License, Version 2.0
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(the "License"); you may not use this file except in compliance with
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the License. You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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---
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### Description
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The `TRUNCATE TABLE` statement removes all the rows from a table or partition(s). The table must not be a view
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or an external/temporary table. In order to truncate multiple partitions at once, the user can specify the partitions
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in `partition_spec`. If no `partition_spec` is specified it will remove all partitions in the table.
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### Syntax
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```sql
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TRUNCATE TABLE table_identifier [ partition_spec ]
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```
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### Parameters
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* **table_identifier**
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Specifies a table name, which may be optionally qualified with a database name.
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**Syntax:** `[ database_name. ] table_name`
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* **partition_spec**
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An optional parameter that specifies a comma separated list of key and value pairs
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for partitions.
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**Syntax:** `PARTITION ( partition_col_name = partition_col_val [ , ... ] )`
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### Examples
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```sql
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-- Create table Student with partition
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CREATE TABLE Student (name STRING, rollno INT) PARTITIONED BY (age INT);
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SELECT * FROM Student;
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+----+------+---+
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|name|rollno|age|
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+----+------+---+
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| ABC| 1| 10|
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| DEF| 2| 10|
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| XYZ| 3| 12|
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+----+------+---+
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-- Removes all rows from the table in the partition specified
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TRUNCATE TABLE Student partition(age=10);
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-- After truncate execution, records belonging to partition age=10 are removed
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SELECT * FROM Student;
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+----+------+---+
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|name|rollno|age|
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+----+------+---+
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| XYZ| 3| 12|
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+----+------+---+
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-- Removes all rows from the table from all partitions
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TRUNCATE TABLE Student;
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SELECT * FROM Student;
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+----+------+---+
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|name|rollno|age|
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+----+------+---+
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+----+------+---+
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```
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### Related Statements
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* [DROP TABLE](sql-ref-syntax-ddl-drop-table.html)
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* [ALTER TABLE](sql-ref-syntax-ddl-alter-table.html)
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