Scala UDF 函数对数组列进行操作并返回自定义值
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【中文标题】Scala UDF 函数对数组列进行操作并返回自定义值【英文标题】：Scala UDF function to operate on Array Column and return custom value 【发布时间】：2020-06-27 18:17:32 【问题描述】：我有 2 个这样的数据集
val jsonStr ="""
"TransactionId": 1,
"TransactionName": "Name",
"Order": 12,
"ReplaceStrings": [
"UNDEFINED","INVALID"
],
"Country" : "China"
"""
val configurations = spark.read.json(Seq(jsonStr).toDS)
这有我所有的配置和过滤器
My Data
val data = Seq((1,"Mindy","Devaney","mdevaney0@cnbc.com","Female","United States","UTF-8"),(2,"Charmain","Clear","candriolli1@miitbeian.gov.cn","Female","**China**","UTF-8"),(3,"Dilan","**UNDEFINED**","dphilipeaux2@jalbum.net","Male","**China**","Windows-1252")).toDF("id","Fname","LName","mailid","Gender","Country","Codepage" )
现在，我的要求是加入具有过滤器的配置数据，并使用上述数据检索相应的结果，因为过滤器应用于中国，所有具有 UNDEFINED 作为值的 LName 都将替换为空字符串。
我尝试放置一些 UDF 将其定义为函数，但坚持如何发送 json 值，它是一个包装数组或尝试使用 Seq 数据类型
如果有人看过类似的案例或想法，请与我分享。
【问题讨论】：
【参考方案1】：检查下面的代码。
scala> data.show(false)
+---+--------+-------------+----------------------------+------+-------------+------------+
|id |Fname |LName |mailid |Gender|Country |Codepage |
+---+--------+-------------+----------------------------+------+-------------+------------+
|1 |Mindy |Devaney |mdevaney0@cnbc.com |Female|United States|UTF-8 |
|2 |Charmain|Clear |candriolli1@miitbeian.gov.cn|Female|**China** |UTF-8 |
|3 |Dilan |**UNDEFINED**|dphilipeaux2@jalbum.net |Male |**China** |Windows-1252|
+---+--------+-------------+----------------------------+------+-------------+------------+
scala> configurations.show(false)
+-------+-----+--------------------+-------------+---------------+
|Country|Order|ReplaceStrings |TransactionId|TransactionName|
+-------+-----+--------------------+-------------+---------------+
|China |12 |[UNDEFINED, INVALID]|1 |Name |
+-------+-----+--------------------+-------------+---------------+
scala> val check = udf((lname:String,replaceStrings:Seq[String]) => if(replaceStrings.map(d => s"**$d**").contains(lname)) "" else lname )
scala> data.join(configurations,data("Country").contains(configurations("Country")),"inner").withColumn("LName",check($"LName",$"ReplaceStrings")).drop(configurations("Country")).show(false)
+---+--------+-----+----------------------------+------+---------+------------+-----+--------------------+-------------+---------------+
|id |Fname |LName|mailid |Gender|Country |Codepage |Order|ReplaceStrings |TransactionId|TransactionName|
+---+--------+-----+----------------------------+------+---------+------------+-----+--------------------+-------------+---------------+
|2 |Charmain|Clear|candriolli1@miitbeian.gov.cn|Female|**China**|UTF-8 |12 |[UNDEFINED, INVALID]|1 |Name |
|3 |Dilan | |dphilipeaux2@jalbum.net |Male |**China**|Windows-1252|12 |[UNDEFINED, INVALID]|1 |Name |
+---+--------+-----+----------------------------+------+---------+------------+-----+--------------------+-------------+---------------+
【讨论】：
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