表达式字符串到Scala中的字符串

Question

我将整个表达式变为String (subCategory == "Serveware Sets") || (category == "Cookware & Bakeware") || (category == "Small Appliances") || (category == "Dinnerware & Serveware")

现在我想将此字符串转换为表达式，以便我可以直接比较subCategory和类别的值。 我怎么能这样做。

Answer 1

可以使用expr：

来完成

val filterExpression = """(subCategory == "Serveware Sets") || (category == "Cookware & Bakeware") || (category == "Small Appliances") || (category == "Dinnerware & Serveware")"""

import org.apache.spark.sql.functions.expr

df
 .where(expr(filterExpression))

Answer 2

您可以将||符号更改为or，以便表达式变为

(subCategory == "Serveware Sets") or (category == "Cookware & Bakeware") or (category == "Small Appliances") or (category == "Dinnerware & Serveware")

然后您应该能够在过滤中使用string表达式，或者从数据帧中选择行。