PostgreSql数据库的神器 FDW

PG的FDW的介绍


本篇简单介绍下PG到Mysql,PG到Hive的“透明网关” ^_^
首先：PG的安装
安装PostgreSQL客户端。
sudo apt-get install postgresql-client
然后：安装PostgreSQL服务器。
sudo apt-get install postgresql
正常情况下，安装完成后，PostgreSQL服务器会自动在本机的5432端口开启
如果还想安装图形管理界面，可以运行下面命令
sudo apt-get install pgadmin3
下一步：创建超级权限用户
sudo -u postgres createuser --superuser syk
创建数据库test
sudo -u postgres createdb -O syk test
最后：测试连接PG
psql -U syk -d test -h 127.0.0.1 -p 5432
到此PG的安装完成。

开始配置FDW
先配置到mysql的

下载到本地解压缩
更改下文件的权限
准备安装：中间需要安装一个pg的扩展开发包dev-9.3
sudo PATH=/usr/local/pgsql/bin/:/usr/local/mysql/bin:$PATH make USE_PGXS=1 install

登录PG开始配置mysql（前提是mysql的用户及库表都已经创建完成）的fdw
CREATE extension mysql_fdw;
CREATE SERVER mysql_server FOREIGN DATA WRAPPER mysql_fdw OPTIONS (HOST '127.0.0.1', PORT '3306');
CREATE USER mapping FOR syk SERVER mysql_server OPTIONS (
username 'sky',
PASSWORD 'sky'
);
CREATE FOREIGN TABLE syk_test2 (
goods_id INT,
goods_type VARCHAR (10),
goods_id2 BIGINT
) SERVER mysql_server OPTIONS (
dbname 'syk',
table_name 'syk_test2'
);
SELECT * FROM syk_test2;
INFO:  Successfully connected to MySQL database syk at server 127.0.0.1 via TCP/IP with cipher (server version: 5.5.49-0ubuntu0.14.04.1, protocol version: 10) 
 goods_id | goods_type | goods_id2 
----------+------------+-----------
      100 | 10010      |         0
      100 | 10011      |         0
       88 | 20010      |         0
       86 | 20110      |         0
        0 | 我我我特色 |         0
        1 | 我我我曹操 |         0

下面这些内容基本是占篇幅的^_^
/*
ERROR:  first column of remote table must be unique for INSERT/UPDATE/DELETE operation #注意这里
#mysql 库上的表结构 没有唯一约束
CREATE TABLE `syk_test2` (
`goods_id` INT (11) NOT NULL DEFAULT '0',
`goods_type` VARCHAR (10) DEFAULT NULL,
`goods_id2` BIGINT (20) NOT NULL DEFAULT '0'
) ENGINE = INNODB DEFAULT CHARSET = utf8;
#添加唯一约束
mysql > ALTER TABLE syk_test2 ADD CONSTRAINT idx_goods_id UNIQUE (goods_id);
ERROR 1142 (42000): ALTER command denied to user 'sky'@'localhost' for table 'syk_test2'
当前用户还没有对这个库执行alter ddl的权限 root用户登录赋予权限
靠没权限，赋予下权限
mysql > GRANT ALTER ON syk.* TO sky@'%';
Query OK, 0 rows affected (0.00 sec)
切换回sky用户再次添加唯一约束
songyunkui@syk_ubuntu:~$ mysql -usky -p -h127.0.0.1
mysql> use syk;
Database changed
mysql > ALTER TABLE syk_test2 ADD CONSTRAINT idx_goods_id UNIQUE (goods_id);
ERROR 1062 (23000): Duplicate entry '100' for key 'idx_goods_id'
汗：测试数据有不唯一的,删除下
mysql > DELETE FROM syk_test2 WHERE goods_id = 100 AND goods_type = 10011;
Query OK, 1 row affected (0.06 sec)
再搞
mysql > ALTER TABLE syk_test2 ADD CONSTRAINT uni_goods_id UNIQUE (goods_id);
Query OK, 0 rows affected (0.44 sec)
Records: 0  Duplicates: 0  Warnings: 0
*/

最后在pg上操作Mysql的表 ^_^
test=# delete from syk_test2 where goods_id=0;
test=# 
test=# select * from syk_test2;
 goods_id | goods_type | goods_id2 
----------+------------+-----------
        1 | 我我我曹操 |         0
       86 | 20110      |         0
       88 | 20010      |         0
      100 | 10010      |         0
(4 rows)

########## FDW to HIVE

$ python setup.py sdist
$ sudo python setup.py install

DROP EXTENSION multicorn;
CREATE EXTENSION multicorn;
DROP SERVER multicorn_hive;
CREATE SERVER multicorn_hive FOREIGN DATA WRAPPER multicorn OPTIONS (
WRAPPER 'hivefdw.HiveForeignDataWrapper'
);
CREATE USER MAPPING FOR PUBLIC SERVER multicorn_hive;

DROP FOREIGN TABLE hive;
CREATE FOREIGN TABLE hive (
cat_id INT,
cat_name VARCHAR,
cat_name_en VARCHAR,
type INT,
p_id INT,
deep INT
) SERVER multicorn_hive OPTIONS (
HOST 'c3-hadoop-hive01.bj',
PORT '18XXX',
TABLE 'b2c_d.xm_config_cat'
);

\! kinit - kt h_b2c_dc_r.keytab [e-mail]  这里有一个kerberos的验证

SELECT * FROM hive;
DROP FOREIGN TABLE hive_query;

CREATE FOREIGN TABLE hive_query (cat_id INT, cat_name VARCHAR) SERVER multicorn_hive OPTIONS (
HOST 'c3-hadoop-hive01.bj',
PORT '18XXX',
QUERY 'SELECT cat_id,cat_name from b2c_d.xm_config_cat'
);