Help Center/ GaussDB/ M-Compatibility Developer Guide(Centralized)/ SQL Reference/ SQL Syntax/ SQL Statements/ P/ PURGE
Updated on 2025-10-23 GMT+08:00
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PURGE

Description

The PURGE statement can be used to:

  • Clear tables or indexes from the recycle bin and release all space related to the objects.
  • Clear the recycle bin.

Precautions

  • The PURGE operation supports tables (PURGE TABLE), indexes (PURGE INDEX), and recycle bins (PURGE RECYCLEBIN).

  • The permission requirements for performing the PURGE operation are as follows:

    • PURGE TABLE: The user must be the owner of the table and must have the USAGE permission on the schema to which the table belongs. When the separation of duties is disabled, the system administrator has this permission by default.
    • PURGE INDEX: The user must be the owner of the index and must have the USAGE permission for the schema to which the index belongs. When the separation of duties is disabled, the system administrator has this permission by default.
    • PURGE RECYCLEBIN: Common users can clear only the objects owned by themselves in the recycle bin. Additionally, the user must have the USAGE permission of the schema to which the objects belong. When the separation of duties is disabled, the system administrator has this permission by default.

Prerequisites

  • The enable_recyclebin parameter has been enabled to enable the recycle bin. Contact an administrator. for details about how to use the parameter.
  • The recyclebin_retention_time parameter has been set for specifying the retention period of objects in the recycle bin. The objects will be automatically deleted after the retention period expires. Contact an administrator. for details about how to use the parameter.

Syntax

PURGE { TABLE [schema_name.]table_name          
        | INDEX index_name     
        | RECYCLEBIN 
      };

Parameters

  • schema_name

    Specifies a schema name.

  • TABLE [ schema_name. ] table_name

    Clears a specified table in the recycle bin. The table can be schema-qualified.

  • INDEX index_name

    Clears a specified index in the recycle bin.

  • RECYCLEBIN

    Clears the objects in the recycle bin.

Examples

-- Create a schema.
m_db=# CREATE SCHEMA tpcds;

-- Create the tpcds.reason_t1 table.
m_db=# CREATE TABLE tpcds.reason_t1
 (
  r_reason_sk    integer,
  r_reason_id    character(16),
  r_reason_desc  character(100)
  ) ;
-- Create the tpcds.reason_t2 table.
m_db=# CREATE TABLE tpcds.reason_t2
 (
  r_reason_sk    integer,
  r_reason_id    character(16),
  r_reason_desc  character(100)
  ) ;
-- Create an index on the tpcds.reason_t1 table.
m_db=# CREATE INDEX index_t1 on tpcds.reason_t1(r_reason_id); 
m_db=# CREATE INDEX index_t2 on tpcds.reason_t2(r_reason_id);
m_db=# DROP TABLE tpcds.reason_t1;
m_db=# DROP TABLE tpcds.reason_t2;

-- Check the recycle bin.
m_db=# SELECT rcyname,rcyoriginname,rcytablespace FROM pg_catalog.gs_recyclebin;
           rcyname            | rcyoriginname | rcytablespace 
------------------------------+---------------+---------------
 BIN$41512338419D$87EAEB8==$0 | reason_t1     |             0
 BIN$4151233841A3$87EBBE0==$0 | index_t1      |             0
 BIN$4151233841A0$87EC6A0==$0 | reason_t2     |             0
 BIN$4151233841A4$87ED0F0==$0 | index_t2      |             0
(4 rows)

-- Purge the table.
m_db=# PURGE TABLE tpcds.reason_t2;
m_db=# SELECT rcyname,rcyoriginname,rcytablespace FROM pg_catalog.gs_recyclebin;

-- Purge the index.
m_db=# PURGE INDEX tpcds.index_t1;
m_db=# SELECT rcyname,rcyoriginname,rcytablespace FROM pg_catalog.gs_recyclebin;
           rcyname            | rcyoriginname | rcytablespace 
------------------------------+---------------+---------------
 BIN$41512338419D$87EAEB8==$0 | reason_t1     |             0
 BIN$4151233841A3$87EBBE0==$0 | index_t1      |             0
(2 rows)

-- Purge all objects
m_db=# PURGE recyclebin;
m_db=# SELECT rcyname,rcyoriginname,rcytablespace FROM pg_catalog.gs_recyclebin;
 rcyname | rcyoriginname | rcytablespace 
---------+---------------+---------------
(0 rows)

-- Delete the schema.
 m_db=# DROP SCHEMA tpcds;
Parent topic: P