scala 用于 DataFrame 的 Spark 隐式 $
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Spark Implicit $ for DataFrame
提问by Ben Nelson
Where in the sqlContext.implicits._does it define the $"string" to represent a dataframe call to the parent dataframe's column? Specifically I was confused on seeing something like the following:
它在哪里sqlContext.implicits._定义了 $"string" 来表示对父数据框列的数据框调用？具体来说，我对看到以下内容感到困惑：
import sqlContext.implicits._
df.where($"type".isin("type1","type2") and $"status".isin("completed","inprogress"))
回答by user2844511
If you see the following link
如果您看到以下链接
class SQLContext.implicits$.StringToColumn
Converts $"col name" into an Column.
类 SQLContext.implicits$.StringToColumn
将 $"col name" 转换为 Column。
