2026-03-12 20:23:15

tpt/demos/exchange_partition.sql

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+-- Copyright 2018 Tanel Poder. All rights reserved. More info at http://tanelpoder.com
+-- Licensed under the Apache License, Version 2.0. See LICENSE.txt for terms & conditions.
+
+--drop table mytab;
+--drop table tmp;
+
+-- this is our "source table"
+create table mytab as select * from all_objects;
+create index i on mytab(owner);
+
+-- this is where we copy only needed rows:
+create table tmp 
+partition by range (owner) (
+  partition p1 values less than (maxvalue)
+)
+as
+select * from mytab 
+where owner != 'SYS'
+/
+
+-- in order to do partition exchange, the physical structure of source table and target need to be the same (including indexes):
+create index i_tmp on tmp(owner) local;
+
+-- get rid of old rows
+truncate table mytab;
+
+-- exchange the tmp.p1 partition segment with mytab's segment
+alter table tmp exchange partition p1 with table mytab including indexes;
+
+-- you may need to run this to validate any constraints if they're in novalidate status
+alter table mytab constraint <constraint_name> enable validate;