Apache Doris 代碼倉庫地址：apache/incubator-doris 歡迎大家關(guān)注加星

1.概述

ODBC External Table Of Doris 提供了Doris通過數(shù)據(jù)庫訪問的標(biāo)準(zhǔn)接口(ODBC)來訪問外部表，外部表省去了繁瑣的數(shù)據(jù)導(dǎo)入工作，讓Doris可以具有了訪問各式數(shù)據(jù)庫的能力，并借助Doris本身的OLAP的能力來解決外部表的數(shù)據(jù)分析問題：

1. 支持各種數(shù)據(jù)源接入Doris
2. 支持Doris與各種數(shù)據(jù)源中的表聯(lián)合查詢，進(jìn)行更加復(fù)雜的分析操作
3. 通過insert into將Doris執(zhí)行的查詢結(jié)果寫入外部的數(shù)據(jù)源

本文主要介紹Doris ODBC的安裝使用方式

這里以最常用的Mysql為例。

2.ODBC驅(qū)動(dòng)安裝

2.1 安裝Mysql ODBC驅(qū)動(dòng)

Mysql ODBC驅(qū)動(dòng)下載地址：https://dev.mysql.com/downloads/connector/odbc/

這里我們下載的是RPM安裝包：mysql-connector-odbc-8.0.11-1.el7.x86_64.rpm

然后執(zhí)行

yum localinstall -y mysql-connector-odbc-8.0.11-1.el7.x86_64.rpm

2.2 配置Mysql ODBC驅(qū)動(dòng)

編輯 /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 測(cè)試驅(qū)動(dòng)

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

一般是通過uncode 方式連接，Driver 必須是MySQL ODBC 8.0 Driver ，

其他參數(shù)按mysql server 的設(shè)置。Database 選擇已經(jīng)建立好的數(shù)據(jù)庫。

2.4 測(cè)試ODBC連接

執(zhí)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

3. 配置Doris be ODBC

Doris 使用ODBC連接mysql或者其他數(shù)據(jù)庫，只需要在BE節(jié)點(diǎn)安裝和配置ODBC即可

修改BE節(jié)點(diǎn)odbc配置信息

├── bin
│   ├── be.pid
│   ├── start_be.sh
│   └── stop_be.sh
├── conf
│   ├── be.conf
│   └── odbcinst.ini   //修改這個(gè)文件的配置信息
├── lib
│   ├── meta_tool
│   ├── palo_be
│   ├── small_file
│   ├── udf
│   └── udf-runtime

示例：

我這里只使用了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

配置完以后重啟BE即可，所有BE節(jié)點(diǎn)操作一樣

4. Doris 使用ODBC訪問外部數(shù)據(jù)源

4.1 不使用Resource方式訪問

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",  --注意這里的名稱和odbcinst.ini里的mysql[]里的名稱一致
"odbc_type" = "mysql"
);

然后在doris里執(zhí)行查詢驗(yàn)證

4.2 通過ODBC_Resource來創(chuàng)建ODBC外表 (推薦使用的方式)

首先創(chuàng)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",  --注意這里的名稱和odbcinst.ini里的mysql[]里的名稱一致
"odbc_type" = "mysql"
);

然后創(chuàng)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"
);