1.概述
ODBC External Table Of Doris 提供了Doris通过数据库访问的标准接口(ODBC)来访问外部表，外部表省去了繁琐的数据导入工作，让Doris可以具有了访问各式数据库的能力，并借助Doris本身的OLAP的能力来解决外部表的数据分析问题：
支持各种数据源接入Doris
支持Doris与各种数据源中的表联合查询，进行更加复杂的分析操作
通过insert into将Doris执行的查询结果写入外部的数据源
本文主要介绍Doris ODBC的安装使用方式
这里以最常用的Mysql为例。
2.ODBC驱动安装
2.1 安装Mysql ODBC驱动
Mysql ODBC驱动下载地址：https://dev.mysql.com/downloads/connector/odbc/
这里我们下载的是RPM安装包：mysql-connector-odbc-8.0.11-1.el7.x86_64.rpm
然后执行
yum localinstall -y mysql-connector-odbc-8.0.11-1.el7.x86_64.rpm
2.2 配置Mysql ODBC驱动
编辑 /etc/odbcinst.ini
[MySQL]
Description=ODBC for MySQL
Driver=/usr/lib/libmyodbc5.so
Setup=/usr/lib/libodbcmyS.so
Driver64=/usr/lib64/libmyodbc5.so
Setup64=/usr/lib64/libodbcmyS.so
FileUsage=1
[MySQL ODBC 8.0 Unicode Driver]
Driver=/usr/lib64/libmyodbc8w.so
UsageCount=1
[MySQL ODBC 8.0 ANSI Driver]
Driver=/usr/lib64/libmyodbc8a.so
UsageCount=1
2.3 测试驱动
配置 /etc/odbc.ini
[mysql]
Description = Data source MySQL
Driver = MySQL ODBC 8.0 Driver
Server = 192.168.1.120
Host = 192.168.1.120
Database = dbname
Port = 3306
User = root
Password = 123456
一般是通过uncode 方式连接，Driver 必须是MySQL ODBC 8.0 Driver ，
其他参数按mysql server 的设置。Database 选择已经建立好的数据库。
2.4 测试ODBC连接
执行:
$ isql mysql
+---------------------------------------+
| Connected! |
| |
| sql-statement |
| help [tablename] |
| quit |
| |
+---------------------------------------+
SQL> select * from test limit 2;
+---------------------------------------------------+-----------+
| name | age |
+---------------------------------------------------+-----------+
| zhangfeng | 20 |
| zhang | 22 |
+---------------------------------------------------+-----------+
SQLRowCount returns 2
2 rows fetched
一切正常
- 配置Doris be ODBC
Doris 使用ODBC连接mysql或者其他数据库，只需要在BE节点安装和配置ODBC即可
修改BE节点odbc配置信息
├── bin
│ ├── be.pid
│ ├── start_be.sh
│ └── stop_be.sh
├── conf
│ ├── be.conf
│ └── odbcinst.ini //修改这个文件的配置信息
├── lib
│ ├── meta_tool
│ ├── palo_be
│ ├── small_file
│ ├── udf
│ └── udf-runtime
示例：
我这里只使用了Mysql
# Driver from the postgresql-odbc package
# Setup from the unixODBC package
[PostgreSQL]
Description = ODBC for PostgreSQL
Driver = /usr/lib/psqlodbc.so
Setup = /usr/lib/libodbcpsqlS.so
FileUsage = 1
# Driver from the mysql-connector-odbc package
# Setup from the unixODBC package
#[MySQL ODBC 8.0 Unicode Driver]
#Description = ODBC for MySQL
#Driver = /usr/lib64/libmyodbc8w.so
#FileUsage = 1
[MySQL Driver]
Description = ODBC for MySQL
Driver = /usr/lib/libmyodbc8a.so
FileUsage = 1
# Driver from the oracle-connector-odbc package
# Setup from the unixODBC package
[Oracle 19 ODBC driver]
Description=Oracle ODBC driver for Oracle 19
Driver=/usr/lib/libsqora.so.19.1
配置完以后重启BE即可，所有BE节点操作一样
- Doris 使用ODBC访问外部数据源
4.1 不使用Resource方式访问
CREATE EXTERNAL TABLE `test_mysql` (
`k1` decimal(9, 3) NOT NULL COMMENT "",
`k2` char(10) NOT NULL COMMENT "",
`k3` datetime NOT NULL COMMENT "",
`k5` varchar(20) NOT NULL COMMENT "",
`k6` double NOT NULL COMMENT ""
) ENGINE=ODBC
COMMENT "ODBC"
PROPERTIES (
"host" = "192.168.0.1",
"port" = "3306",
"user" = "root",
"password" = "123456",
"database" = "test",
"table" = "test",
"driver" = "MySQL Driver", --注意这里的名称和odbcinst.ini里的mysql[]里的名称一致
"odbc_type" = "mysql"
);
然后在doris里执行查询验证
4.2 通过ODBC_Resource来创建ODBC外表 (推荐使用的方式)
首先创建Resource
CREATE EXTERNAL RESOURCE `mysql_odbc`
PROPERTIES (
"type" = "odbc_catalog",
"host" = "192.168.0.1",
"port" = "3306",
"user" = "root",
"password" = "123456",
"driver" = "MySQL Driver", --注意这里的名称和odbcinst.ini里的mysql[]里的名称一致
"odbc_type" = "mysql"
);
然后创建 ODBC 外表
CREATE EXTERNAL TABLE `test_mysql` (
`k1` decimal(9, 3) NOT NULL COMMENT "",
`k2` char(10) NOT NULL COMMENT "",
`k3` datetime NOT NULL COMMENT "",
`k5` varchar(20) NOT NULL COMMENT "",
`k6` double NOT NULL COMMENT ""
) ENGINE=ODBC
COMMENT "ODBC"
PROPERTIES (
"odbc_catalog_resource" = "mysql_odbc",
"database" = "test",
"table" = "baseall"
);
