Deleting Partitions by Specifying Filter Criteria (Only OBS Tables Supported)

Function

This statement is used to delete one or more partitions based on specified conditions.

Precautions

Syntax

1
2
3
ALTER TABLE [db_name.]table_name
  DROP [IF EXISTS]
  PARTITIONS partition_filtercondition;

Keyword

Parameters

Table 1 Parameter description

Parameter

Description

db_name

Database name that contains letters, digits, and underscores (_). It cannot contain only digits or start with an underscore (_).

table_name

Table name of a database that contains letters, digits, and underscores (_). It cannot contain only digits or start with an underscore (_). The matching rule is ^(?!_)(?![0-9]+$)[A-Za-z0-9_$]*$. If special characters are required, use single quotation marks ('') to enclose them.

This statement is used for OBS table operations.

partition_filtercondition

Condition used to search partitions to be deleted. The format is as follows:

  • Partition column name Operator Value to compare

    Example: start_date < '201911'

  • <partition_filtercondition1> AND|OR <partition_filtercondition2>

    Example: start_date < '201911' OR start_date >= '202006'

  • (<partition_filtercondition1>) [,partitions (<partition_filtercondition2>), ...]

    Example: (start_date <> '202007'), partitions(start_date < '201912')

Example

You can run the following statements to delete partitions of the student table using different conditions:

1
2
3
4
5
6
7
8
alter table student drop partitions(start_date < '201911');
alter table student drop partitions(start_date >= '202007');
alter table student drop partitions(start_date BETWEEN '202001' AND '202007');
alter table student drop partitions(start_date < '201912' OR start_date >= '202006');
alter table student drop partitions(start_date > '201912' AND start_date <= '202004');
alter table student drop partitions(start_date != '202007');
alter table student drop partitions(start_date <> '202007');
alter table student drop partitions(start_date <> '202007'), partitions(start_date < '201912');
Parent topic: Syntax for Partitioning a Table