[TOC] # 您需要知道的 - ORACLE 19c 版本中 ADG 备库 DML 重定向功能，一个很 Interesting 的新特性 - Data Guard 环境是基于CDB模式，主库 CDB1（PDB1），备库 CDB1（PDB1） - 实验是在备库的 PDB1 数据库中进行的 DML 重定向 - 重定向功能不支持 SYS 用户 - 如有必要，您可参考 [G007-ORACLE-INS-DG-01](http://blog.itpub.net/69986162/viewspace-2731012/) 一文构建本实验环境 # 1 备库DML重定向流程  - 1 备库执行 DML 语句 - 2 语句被重定向到主库 - 3 主库应用 DML 语句 - 4 数据更改流传备库执行 - 5 数据展示给客户端 # 2 主库查询条目数 ```sql SQL> alter session set container=pdb1; Session altered. SQL> create user askscuti identified by askscuti; User created. SQL> grant dba to askscuti; Grant succeeded. SQL> conn askscuti/askscuti@pdb1; Connected. SQL> create table askscuti as select object_id from dba_objects; Table created. SQL> select count(1) from askscuti; COUNT(1) ---------- 72374 ``` # 3 备库查询条目数 ```sql SQL> alter pluggable database pdb1 open; Pluggable database altered. SQL> show pdbs CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 PDB1 READ ONLY NO SQL> conn askscuti/askscuti@pdb1; Connected. SQL> select count(1) from askscuti; COUNT(1) ---------- 72374 ``` # 4 主库插入数据 ```sql SQL> insert into askscuti values(72375); 1 row created. SQL> commit; Commit complete. SQL> select count(1) from askscuti; COUNT(1) ---------- 72375 ``` # 5 备库插入数据 ```sql SQL> select count(1) from askscuti; COUNT(1) ---------- 72375 SQL> insert into askscuti values(72376); insert into askscuti values(72376) * ERROR at line 1: ORA-16000: database or pluggable database open for read-only access # 备库开启当前会话重定向功能 SQL> alter session enable adg_redirect_dml; Session altered. SQL> insert into askscuti values(72376); 1 row created. SQL> commit; Commit complete. SQL> select count(1) from askscuti; COUNT(1) ---------- 72376 ``` # 6 主库再次查询条目数 ```sql SQL> select count(1) from askscuti; COUNT(1) ---------- 72376 ``` [End]