在Spark SQL中,可以使用cast函数来实现Long类型到String类型的转换。cast函数用于强制类型转换,可以将Long类型的数据转换为String类型。下面是一个示例代码: ```sql SELECT cast(12345 AS STRING) AS converted_string 1. 2. 上面的代码中,我们将Long类型的数据`12345`通过`cast`
day(current_date) as day, hour(current_timestamp) as hour, minute(current_timestamp) as minute, second(current_timestamp) as second; select year(current_date) as year, ( case length(cast( month(current_date) as string) ) when 1 then concat( '0' , cast( month(current_date) as stri...
select t1.id, t1.id_rand, t2.name from ( select id , case when id = null then concat(‘SkewData_’, cast(rand() as string)) else id end as id_rand from test1 where statis_date =‘20221130’) t1 left join test2 t2 on t1.id_rand = t2.id 针对Spark3,可以在EMR控制台Spark3服...
将age列修改为String类型,将 isGraduated列修改为布尔类型,将jobStartDate修改为日期类型。 import org.apache.spark.sql.functions._ val df2 = df.withColumn("age",col("age").cast(StringType)) .withColumn("isGraduated",col("isGraduated").cast(BooleanType)) .withColumn("jobStartDate",col("jobStart...
我有一个配置单元查询,它使用一个表中声明为string的值和另一个表中声明为bigint的值连接两个表。字符串和bigint中的实际数据是相同的。此查询在配置单元中运行良好 SELECT TABLE1.* FROM TABLE1 LEFT OUTER JOIN TABLE2 ON TABLE1.<STRING COLUMN> = cast(TABLE2.<BIGINT COLUMN> as string) 但是当我...
通过调用withColumn方法,我们在原有DataFrame上创建了一个新的列value_as_decimal,并使用cast将value列转换为Decimal类型。这里的DecimalType(10, 2)表示我们希望小数的总长度为10位,其中小数点后2位。 步骤5:显示转换后的结果 最后,展示转换后的数据结果,以确认转换是否成功。
df.selectExpr("CAST(key AS STRING)", "CAST(value AS STRING)") 使用Spark作为Producer发送Kafka数据: 代码语言:txt AI代码解释 # Write key-value data from a DataFrame to a Kafka topic specified in an option query = df \ .selectExpr("CAST(userId AS STRING) AS key", "to_json(struct(*))...
.select($"value".cast("string")) .as[String] .writeStream .outputMode("complete") .format("console") 3、Process Time vs Event Time Process Time:流处理引擎接收到数据的时间 Event Time:时间真正发生的时间 Spark Streaming Spark Streaming中由于其微批的概念,会将一段时间内接收的数据放入一个批内...
selectExpr("CAST(value AS STRING)") \ .select(from_json(col("value"), schema).alias("data")) \ .select("data.*") return transformed_df def initiate_streaming_to_bucket(df, path, checkpoint_location): """ Start streaming the transformed data to the specified S3 bucket in parquet ...
u"\nDataType varchar is not supported.cast(cid as varchar) 改成 cast(cid as string)Error...