ClickHouse报错-无法检测左右连接键

ClickHouse报错-无法检测左右连接键

版本: 20.4.5

1.报错的原因

创建物化视图sql如下

CREATE MATERIALIZED VIEW sc_view ( id UInt8 , name String , age UInt8, class String ) ENGINE = MergeTree()
ORDER BY
(id) POPULATE AS
SELECT
	s.id,
	s.name,
	s.age,
	c.name As class
FROM
	student 
LEFT JOIN class ON s.id = c.id
ORDER BY
	s.id ;

报错:

Cannot detect left and right JOIN keys. JOIN ON section is ambiguous

无法检测左右连接键。节上的连接是模糊的

原因:

这是目前CH的一个BUG,将sql语句改为以下的格式即可

CREATE MATERIALIZED VIEW sc_view ( id UInt8 , name String , age UInt8, class String ) ENGINE = MergeTree()
ORDER BY
(id) POPULATE AS
SELECT
	student.id,
	student.name,
	student.age,
	class.name As class
FROM
	student 
LEFT JOIN class ON student.id = class.id
ORDER BY
	student.id ;