July 2023
Intermediate to advanced
278 pages
5h 40m
Chinese
Content preview from Trino 权威指南：原书第2版
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134
|
第
8
章
除了
Trino
运行时、集群以及工作节点等信息外，
Trino
连接器还能够暴露其连接的数据
源中的系统数据。例如，可以在
datalake
catalog
中配置使用
Hive
连接器，它可以自
动将
Hive
的系统表暴露出来：
SHOW TABLES FROM datalake.system;
结果中包含了诸如已用分区等方面的信息。
8.3 catalog
如第
6
章所述，
Trino catalog
表示在
catalog
属性文件中使用连接器配置的数据源。
catalog
包含一个或多个
schema
，而
schema
提供了表的集合。
例如，你可以配置一个
PostgreSQL catalog
来访问
PostgreSQL
上的关系型数据库；也
可以配置一个
JMX catalog
，通过
JMX
连接器对
JMX
信息进行访问；还可以通过使用
Iceberg
连接器连接到使用
Iceberg
表格式的对象存储数据源的
catalog
，或配置
Pinot
连
接器来访问实时分布式
OLAP
数据存储。当在
Trino
中运行一条
SQL
语句时，你是在一
个或多个
catalog
上运行它。
多个
catalog
可以使用同一个连接器。例如，你可以创建两个独立的
catalog
来暴露两个
运行在同一服务器上的
PostgreSQL
数据库。
在
Trino
中，完全限定表总是从
catalog
开始，然后到
schema
和表名。比如，完全限
定表
deltalake.test_data.test
指的是
deltalake
catalog
中
test_data
schema
下的
test
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
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.