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`函数转换为String类型,并将结果命名...
-- 创建示例表CREATETABLEsales_data(idINT,revenueDECIMAL(10,2));-- 插入示例数据INSERTINTOsales_dataVALUES(1,123.45);INSERTINTOsales_dataVALUES(2,67.89);INSERTINTOsales_dataVALUES(3,100.00);-- 执行数值转字符查询SELECTid,CAST(revenueASSTRING)ASrevenue_strFROMsales_data; 1. 2. 3. 4. 5. 6. 7...
selectt1.id, t1.id_rand, t2.namefrom(selectid ,casewhenid=nullthenconcat(‘SkewData_’,cast(rand()asstring))elseidendasid_randfromtest1wherestatis_date=‘20221130’) t1leftjointest2 t2ont1.id_rand=t2.id 针对Spark3,可以在EMR控制台Spark3服务的配置页签,修改spark.sql.adaptive.enabled和spar...
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...
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)) ...
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...
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(*))...
u"\nDataType varchar is not supported.cast(cid as varchar) 改成 cast(cid as string)Error...
.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...
- cast('12.5' as decimal) 结果是:12 精度和小数位数默认值分别是18与0。如果在decimal类型中不提供这两个值,将截断小数部分,并不会像第二个例子一样报错。 三、数学运算 round 四舍五入 floor 取左值 ceil 取右值 例子: select round(1.2356); +---+ |round(1.2356, 0)| +---+ | 1| +---+...