我有3个DataFrame:
1. Item dataframe:
+-------+---------+
|id_item|item_code|
+-------+---------+
| 991| A0049|
| 992| C1248|
| 993| C0860|
| 994| C0757|
| 995| C0682|
+-------+---------+
和
2. User dataframe:
+------+--------+
|id_usn| usn|
+------+--------+
|417567|39063291|
|417568|39063294|
|417569|39063334|
|417570|39063353|
|417571|39063376|
+------+--------+
和
3. Summary dataframe
+-------+--------------------+
|id_item| summary |
+-------+--------------------+
| 991|[[417567,0.579901...|
| 992|[[417567,0.001029...|
| 443|[[417585,0.219624...|
+-------+--------------------+
and schema of this dataFrame:
root
|-- id_item: integer (nullable = true)
|-- summary: array (nullable = true)
| |-- element: struct (containsNull = true)
| | |-- id_usn: long (nullable = true)
| | |-- rating: double (nullable = true)
现在,在StructType中 id_usn ,我希望在User DataFrame中通过 usn 在Summary DataFrame中替换 id_usn ,
我正在使用Spark!
请解决这个问题!
答案 0 :(得分:1)
希望它有所帮助。
from pyspark.sql import functions as F
sdf1 = summarydf.select('id_item','summary',F.explode('summary').alias('col_summary')).select('*',F.col('col_summary').id_usn.alias('id_usn'),F.col('col_summary').rating.alias('rating')).drop('col_summary')
df = sdf1.join(itemdf,'id_item').join(userdf,'id_usn').select('item_code',F.struct('usn','rating').alias('tmpcol')).groupby('item_code').agg(F.collect_list('tmpcol').alias('summary'))
+---------+--------------------+
|item_code| summary|
+---------+--------------------+
| C1248|[[39063291,0.0010...|
| A0049|[[39063291,0.5799...|
+---------+--------------------+