📢📢📢📣📣📣
哈喽！大家好，我是【IT邦德】，江湖人称jeames007，10余年DBA及大数据工作经验
一位上进心十足的【大数据领域博主】！😜😜😜
中国DBA联盟(ACDU)成员，目前服务于工业互联网
擅长主流Oracle、MySQL、PG、高斯及Greenplum运维开发，备份恢复，安装迁移，性能优化、故障应急处理等。
✨ 如果有对【数据库】感兴趣的【小可爱】，欢迎关注【IT邦德】💞💞💞
❤️❤️❤️感谢各位大可爱小可爱！❤️❤️❤️

前言

本文详细介绍了我的旅程、从Oracle迁移到PostgreSQL遇到的挑战,我希望分享这些经验将使你的PostgreSQL之旅更加顺利.

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📣 1.Ora2Pg介绍

Ora2Pg是我的第一个盟友。
它是一个开源工具，可将Oracle数据库模式转换为PostgreSQL格式。
可以处理大量的甲骨文对象
可通过配置文件进行配置
https://ora2pg.darold.net/

特点：
支持导出数据库绝大多数对象类型，包括表、视图、序列、索引、外键、约束、函数、存储过程等。
提供PL/SQL到PL/PGSQL语法的自动转换，一定程度避免了人工修正。
可生成迁移报告，包括迁移难度评估、人天估算。
可选对导出数据进行压缩，节约磁盘开销。
配置选项丰富，可自定义迁移行为。

📣 2.ora2pg安装

✨ 2.1 安装依赖包

yum install -y gcc perl-DBD-Pg perl perl-devel perl-DBI perl-CPAN bzip2
perl-ExtUtils-eBuilder perl-ExtUtils-MakeMaker perl-Time-HiRes perl-tests perf cpan

✨ 2.2 正式安装

perl -MCPAN -e ‘install DBI’
perl -MCPAN -e ‘install DBD::Oracle’
perl -MCPAN -e ‘install DBD::Pg’

📣 3.相关配置

✨ 3.1 表结构配置

cat > /etc/ora2pg/ora2pg_table_ddl.conf <<“EOF”
ORACLE_HOME /usr/lib/oracle/21/client64
ORACLE_DSN dbi:Oracle:host=172.18.12.90;sid=oradb;port=1521
#ORACLE_DSN dbi:Oracle:host=192.168.1.29;service_name=pdb1;port=1521
#ORACLE_DSN dbi:Oracle:tns_ora19c
ORACLE_USER system
ORACLE_PWD oracle
SCHEMA STEST
EXPORT_SCHEMA 1
CREATE_SCHEMA 1
TYPE TABLE
PG_NUMERIC_TYPE 0
PG_INTEGER_TYPE 1
DEFAULT_NUMERIC float
SKIP fkeys checks
#SKIP keys pkeys ukeys indexes checks
NLS_LANG AMERICAN_AMERICA.UTF8
OUTPUT_DIR /tmp
OUTPUT ora2pg_table_ddl.sql
PG_VERSION 14
EOF

✨ 3.2 表数据的配置文件

cat > /etc/ora2pg/ora2pg_table_data.conf <<“EOF”
ORACLE_HOME /usr/lib/oracle/21/client64
ORACLE_DSN dbi:Oracle:host=172.18.12.90;sid=oradb;port=1521
#ORACLE_DSN dbi:Oracle:tns_ora19c
ORACLE_USER system
ORACLE_PWD oracle
SCHEMA STEST
TYPE COPY
PG_NUMERIC_TYPE 0
PG_INTEGER_TYPE 1
DEFAULT_NUMERIC float
SKIP fkeys checks
#SKIP fkeys pkeys ukeys indexes checks
NLS_LANG AMERICAN_AMERICA.UTF8
OUTPUT_DIR /tmp
OUTPUT ora2pg_table_data.sql
PG_DSN dbi:Pg:dbname=jemdb;host=172.18.12.50;port=5432
PG_USER postgres
PG_PWD jeames
PG_SCHEMA stest
PG_VERSION 14
EOF

📣 4.ora2pg迁移数据

✨ 4.1 迁移全部表结构

mkdir -p /ora2pg
ora2pg -c /etc/ora2pg/ora2pg_table_ddl.conf -t table -b /ora2pg

✨ 4.2 PG中创建数据

su - postgres
psql
CREATE USER STEST WITH password ‘post’ CREATEDB SUPERUSER replication createrole login;
create database jemdb;
alter database jemdb owner to STEST;
\c jemdb

– 跑脚本
\i /ora2pg/ora2pg_table_ddl.sql
jemdb=# \d

✨ 4.3 迁移数据

ora2pg -d -t copy -c /etc/ora2pg/ora2pg_table_data.conf -P 12 -L 100000 -j 12
此过程执行完成后，数据就已经插入到PG数据库中了：

📣 5.数据验证

su - postgres
psql
\c jemdb

emdb=# show search_path;
   search_path   
-----------------
 "$user", public
(1 row)

jemdb=# set search_path=stest,public;
SET
jemdb=# \dt
                List of relations
 Schema |         Name         | Type  |  Owner   
--------+----------------------+-------+----------
 stest  | addresses            | table | postgres
 stest  | card_details         | table | postgres
 stest  | customers            | table | postgres
 stest  | inventories          | table | postgres
 stest  | logon                | table | postgres
 stest  | order_items          | table | postgres
 stest  | orderentry_metadata  | table | postgres
 stest  | orders               | table | postgres
 stest  | product_descriptions | table | postgres
 stest  | product_information  | table | postgres
 stest  | warehouses           | table | postgres
(11 rows)

jemdb=# select  nspname AS schemaname,
jemdb-# relname,
jemdb-# reltuples::numeric as rowcount,
jemdb-# pg_size_pretty (
jemdb(# pg_total_relation_size ( '"' || nspname || '"."' || relname || '"' )) AS SIZE
jemdb-# from    pg_class C LEFT JOIN pg_namespace N ON ( N.oid = C.relnamespace ) 
jemdb-# where   nspname NOT IN ( 'pg_catalog', 'information_schema' ) 
jemdb-# AND relkind = 'r' 
jemdb-# ORDER by reltuples DESC 
jemdb-# LIMIT 20;
 schemaname |       relname        | rowcount |    size    
------------+----------------------+----------+------------
 stest      | inventories          |   899441 | 433 MB
 stest      | order_items          |     7341 | 1072 kB
 stest      | logon                |     2383 | 160 kB
 stest      | card_details         |     1500 | 264 kB
 stest      | addresses            |     1500 | 264 kB
 stest      | orders               |     1430 | 376 kB
 stest      | warehouses           |     1000 | 192 kB
 stest      | customers            |     1000 | 440 kB
 stest      | product_descriptions |     1000 | 288 kB
 stest      | product_information  |     1000 | 400 kB
 stest      | orderentry_metadata  |       -1 | 8192 bytes
(11 rows)

jemdb=# \l
                                  List of databases
   Name    |  Owner   | Encoding |   Collate   |    Ctype    |   Access privileges   
-----------+----------+----------+-------------+-------------+-----------------------
 jemdb     | stest    | UTF8     | en_US.UTF-8 | en_US.UTF-8 | 
 postgres  | postgres | UTF8     | en_US.UTF-8 | en_US.UTF-8 | 
 template0 | postgres | UTF8     | en_US.UTF-8 | en_US.UTF-8 | =c/postgres          +
           |          |          |             |             | postgres=CTc/postgres
 template1 | postgres | UTF8     | en_US.UTF-8 | en_US.UTF-8 | =c/postgres          +
           |          |          |             |             | postgres=CTc/postgres
(4 rows)

jemdb=# \dn
  List of schemas
  Name  |  Owner   
--------+----------
 public | postgres
 stest  | stest
(2 rows)

jemdb=# \du
                                   List of roles
 Role name |                         Attributes                         | Member of 
-----------+------------------------------------------------------------+-----------
 postgres  | Superuser, Create role, Create DB, Replication, Bypass RLS | {}
 stest     | Superuser, Create role, Create DB, Replication             | {}