[英]PySpark - rename key names in JSON stored as string column in CSV file
我想更新存儲為字符串列的 json 中的鍵名,並將其另存為字符串類型列。 我正在從我的 csv 中讀取這些列並將其存儲為 csv。
這就是我的輸入 csv 的樣子。
candidate_email,transactions
cust2@email.com,"[{'transaction_id':'12', 'transaction_amount':'$23.43'},{'transaction_id':'15', 'transaction_amount':'$723.41'}]"
cust1@email.com,"[{'transaction_id':'10', 'transaction_amount':'$55.99'},{'transaction_id':'11', 'transaction_amount':'$20.46'},{'transaction_id':'13', 'transaction_amount':'$5.89'},{'transaction_id':'14', 'transaction_amount':'$35.61'}]"
我想更換transaction_id
與鍵id
和transaction_amount
與amount
在我的JSON和救回來為csv。
input_df = spark.read.csv('transactions/*.csv', header='true', inferSchema = True)
input_df.printSchema()
# root
# |-- candidate_email: string (nullable = true)
# |-- transactions: string (nullable = true)
input_df.show(10, False)
# +-----------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
# |candidate_email|transactions |
# +-----------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
# |cust2@email.com |[{'transaction_id':'12', 'transaction_amount':'$23.43'},{'transaction_id':'15', 'transaction_amount':'$723.41'}] |
# |cust1@email.com |[{'transaction_id':'10', 'transaction_amount':'$55.99'},{'transaction_id':'11', 'transaction_amount':'$20.46'},{'transaction_id':'13', 'transaction_amount':'$5.89'},{'transaction_id':'14', 'transaction_amount':'$35.61'}]|
# +-----------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
如何更換我的鑰匙以獲得以下輸出?
output_df.show(10,False)
# +---------------+----------------------------------------------------------------------------------------------------------------------------+
# |candidate_email|transactions |
# +---------------+----------------------------------------------------------------------------------------------------------------------------+
# |cust1@email.com|[{'id':'10', 'amount':'$55.99'},{'id':'11', 'amount':'$20.46'},{'id':'13', 'amount':'$5.89'},{'id':'14', 'amount':'$35.61'}]|
# |cust2@email.com|[{'id':'12', 'amount':'$23.43'},{'id':'15', 'amount':'$723.41'}] |
# +---------------+----------------------------------------------------------------------------------------------------------------------------+
注意:兩列都是字符串類型的列。
output_df.printSchema()
# root
# |-- candidate_email: string (nullable = true)
# |-- transactions: string (nullable = true)
使用from_json
將交易列作為array(struct...)
讀取,然后轉換為所需的字段名稱。
explode + to_json + groupBy + collect_list
以獲得所需的 json。 Example:
df.show()
#+---------------+----------------------------------------------------------------------------------------------------------------+
#|candidate_email|transactions |
#+---------------+----------------------------------------------------------------------------------------------------------------+
#|cust2@email.com|[{'transaction_id':'12', 'transaction_amount':'$23.43'},{'transaction_id':'15', 'transaction_amount':'$723.41'}]|
#+---------------+----------------------------------------------------------------------------------------------------------------+
st=ArrayType(StructType([StructField("transaction_id", StringType()),StructField("transaction_amount", StringType())]))
df.withColumn("jsn",from_json(col("transactions"),st).cast("array<struct<id:string,amount:string>>")).\
selectExpr("*","explode(jsn)").\
select("*","col.*").\
drop(*drop_cols).\
selectExpr("candidate_email","to_json(struct(id,amount)) as trans").\
groupBy("candidate_email").\
agg(collect_list("trans").alias("transactions")).\
show(10,False)
#+---------------+---------------------------------------------------------------+
#|candidate_email|transactions |
#+---------------+---------------------------------------------------------------+
#|cust2@email.com|[{"id":"12","amount":"$23.43"}, {"id":"15","amount":"$723.41"}]|
#+---------------+---------------------------------------------------------------+
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.