March 2021
Intermediate to advanced
265 pages
6h 50m
Chinese
Content preview from Presto实战
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76
｜
第
6
章
•
适用于使用
Hadoop
分布式文件系统（
HDFS
）和类似对象存储系统查询系统的
Hive
连
接器，参见
6.4
节。
•
与非关系数据源的众多连接器，参见
6.5
节。
•
用于
TPC
基准数据的
tpch
和
tpcds
连接器，参见
6.3
节。
•
用于
Java
管理扩展的连接器（即
JMX
）
，参见
6.6
节。
在本章中，你将了解到更多关于
Presto
项目自带的这些连接器的信息
。目前，
Presto
中已
经有二十多个连接器，而且
Presto
团队和用户社区还在创造更多的连接器
。商业的、专有
的连接器也可用于进一步扩展
Presto
的能力边界和性能
。最后，如果你有一个自定义的数
据源，或者一个没有连接器的数据源，你可以通过实现必要的
SPI
调用来实现你自己的连
接器，然后将它放到
Presto
中的插件目录里中即可。
catalog
和连
接器使用的一个重要方面是，所有这些可同时用于
Presto
中的
SQL
语句和查
询。这意味着你可以创建跨数据源的查询。例如，你可以将来自关系数据库的数据与存储
在对象存储后台的文件中的数据结合起来。这些联邦查询将在
7.6
节中详细讨论。
6.1
配置
如
2.3
节所述，你想访问数据源时需要创建一个
catalog
文件来配置
catalog
。在编写查询
时，文件的名称决定了
catalog
的名称。
必填属性
connector.name
表示
catalog
中使用的是哪个连接器。同一个连接器可以在不同
的
catalog
中多次使用
。例如，使用相同技术（如
PostgreSQL
）访问包含不同数据库的不
同
RDBMS
服务器实例
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.