DataFrame 列名称与 .(dot) 冲突 [英] DataFrame columns names conflict with .(dot)

问题描述

我有一个 DataFrame df 有这个架构:

I have a DataFrame df which has this schema:

root
 |-- person.name: string (nullable = true)
 |-- person: struct (nullable = true)
 |    |-- age: long (nullable = true)
 |    |-- name: string (nullable = true)

当我执行 df.select("person.name") 时，我显然从 person 获取子字段 name.如何选择 person.name 列?

When I do df.select("person.name") I obviously fetch the sub-field name from person. How could I select the column person.name?

推荐答案

对于包含 .(dot) 的列名，您可以使用 ` 字符将列名

For the column name that contains .(dot) you can use the ` character to enclose the column name

df.select("`person.name`") 

这将选择外部字符串 person.name: string (nullable = true)

还有df.select("person.name")

这会得到人名，即结构体

This gets the person name which is struct

 |-- person: struct (nullable = true)
 |    |-- age: long (nullable = true)

如果你有一个列名，你可以在列名前面加上`字符

"`" + columnName + "`"

我希望这有帮助！

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