はSQL
文の中UDF
としてlambda
機能を採用し、検索を実行するために、放送変数の使用を示す、pySpark
で最小限の再現性の例です。
# Create dummy data and register as table
df = sc.parallelize([
(1,"a"),
(2,"b"),
(3,"c")]).toDF(["num","let"])
df.registerTempTable('table')
# Create broadcast variable from local dictionary
myDict = {1: "y", 2: "x", 3: "z"}
broadcastVar = sc.broadcast(myDict)
# Alternatively, if your dict is a key-value rdd,
# you can do sc.broadcast(rddDict.collectAsMap())
# Create lookup function and apply it
sqlContext.registerFunction("lookup", lambda x: broadcastVar.value.get(x))
sqlContext.sql('select num, let, lookup(num) as test from table').show()
+---+---+----+
|num|let|test|
+---+---+----+
| 1| a| y|
| 2| b| x|
| 3| c| z|
+---+---+----+