更新时间:2023-11-13 22:49:58
您可以通过使用 from_json
函数将您的 json 字符串转换为实际的 json 而受益.为此,您必须定义一个与您的 json 字符串匹配的 schema
.最后使用 explode
函数将 struct 数组 分隔到不同的行,就像使用 eval
一样.
You can benefit by using from_json
function to convert your json string to actual json. For that you will have to define a schema
matching to your json string. And finally use explode
function to separate the struct array to different rows as you did with eval
.
如果你有一个数据
x = "[{u'date': u'2015-02-08', u'by': u'abc@gg.com', u'value': u'NA'}, {u'date': u'2016-02-08', u'by': u'dfg@yaa.com', u'value': u'applicable'}, {u'date': u'2017-02-08', u'by': u'wrwe@hot.com', u'value': u'ufc'}]"
然后创建dataframe
df = sqlContext.createDataFrame([(x,),], ["x"])
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
|x |
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
|[{u'date': u'2015-02-08', u'by': u'abc@gg.com', u'value': u'NA'}, {u'date': u'2016-02-08', u'by': u'dfg@yaa.com', u'value': u'applicable'}, {u'date': u'2017-02-08', u'by': u'wrwe@hot.com', u'value': u'ufc'}]|
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
root
|-- x: string (nullable = true)
使用 jsons
正如我所解释的,你需要一个 schema
、regexp_replace
函数、from_json
函数和 explode
函数作为
As I had explained, you would need a schema
, regexp_replace
function, from_json
function and explode
function as
from pyspark.sql import types as T
schema = T.ArrayType(T.StructType([T.StructField('date', T.StringType()), T.StructField('by', T.StringType()), T.StructField('value', T.StringType())]))
from pyspark.sql import functions as F
df = df.withColumn("x", F.explode(F.from_json(F.regexp_replace(df['x'], "(u')", "'"), schema=schema)))
应该给你
+-----------------------------------+
|x |
+-----------------------------------+
|[2015-02-08,abc@gg.com,NA] |
|[2016-02-08,dfg@yaa.com,applicable]|
|[2017-02-08,wrwe@hot.com,ufc] |
+-----------------------------------+
root
|-- x: struct (nullable = true)
| |-- date: string (nullable = true)
| |-- by: string (nullable = true)
| |-- value: string (nullable = true)
如果您需要问题中提到的 json 字符串,那么您可以使用 to_json
函数作为
If you require the json strings as mentioned in the question then you can use to_json
function as
df = df.withColumn("x", F.to_json(df['x']))
这会给你
+-------------------------------------------------------------+
|x |
+-------------------------------------------------------------+
|{"date":"2015-02-08","by":"abc@gg.com","value":"NA"} |
|{"date":"2016-02-08","by":"dfg@yaa.com","value":"applicable"}|
|{"date":"2017-02-08","by":"wrwe@hot.com","value":"ufc"} |
+-------------------------------------------------------------+
仅使用字符串
如果您不想经历 json 的所有复杂性,那么您可以简单地使用字符串.为此,您需要 嵌套 regex_replace
、split
和 explode
函数作为
If you don't want to go through all the complexities of jsons then you can simply work with strings. For that you would need nested regex_replace
, split
and explode
functions as
from pyspark.sql import functions as F
df = df.withColumn("x", F.explode(F.split(F.regexp_replace(F.regexp_replace(F.regexp_replace(df['x'], "(u')", "'"), "[\\[\\]\s]", ""), "},\\{", "};&;{"), ";&;")))
应该给你
+-------------------------------------------------------------+
|x |
+-------------------------------------------------------------+
|{'date':'2015-02-08','by':'abc@gg.com','value':'NA'} |
|{'date':'2016-02-08','by':'dfg@yaa.com','value':'applicable'}|
|{'date':'2017-02-08','by':'wrwe@hot.com','value':'ufc'} |
+-------------------------------------------------------------+