软件开发培训视频_郑州小程序开发报价_百度手机seo软件_百度关键词挖掘工具

一、查询所有数学课程成绩大于语文课程成绩的学生学号

数据

1,yuwen,43
1,shuxue,55
2,yuwen,77
2,shuxue,88
3,yuwen,98
3,shuxue,65
3,yingyu,88

基本步骤：

• 进行行转列
• 比较语文与数学的成绩

SQL代码： 

with t1 as(SELECT id,sum(if(name = 'yuwen',score,0)) chinese,sum(if(name = 'shuxue',score,0)) math,sum(if(name = 'yingyu',score,0)) english FROM zuoye1 group by id)select id from t1 where math>chinese

 sparkSQL代码

import os
import refrom pyspark.sql import SparkSession"""
------------------------------------------Description : TODO：SourceFile : _04-zuoye1Author  : zxxDate  : 2024/11/4
-------------------------------------------
"""
# 查询所有数学课程成绩大于语文课程成绩的学生学号
if __name__ == '__main__':os.environ['JAVA_HOME'] = 'D:/bigdata/03-java/java-8/jdk'# 配置Hadoop的路径，就是前面解压的那个路径os.environ['HADOOP_HOME'] = 'D:/bigdata/04-Hadoop/hadoop/hadoop-3.3.1/hadoop-3.3.1'# 配置base环境Python解析器的路径os.environ['PYSPARK_PYTHON'] = 'D:/bigdata/22-spark/Miniconda3/python.exe'  # 配置base环境Python解析器的路径os.environ['PYSPARK_DRIVER_PYTHON'] = 'D:/bigdata/22-spark/Miniconda3/python.exe'spark = SparkSession.builder.master("local[2]").appName("第一题").config("spark.sql.shuffle.partitions", 2).getOrCreate()df = (spark.sparkContext.textFile("../../datas/zuoye2/zuoye1.txt").map(lambda line: (re.split(",",line)[0],re.split(",",line)[1],re.split(",",line)[2])).toDF(["id","name","score"]))df.createOrReplaceTempView("zuoye1")spark.sql("""with t1 as(SELECT id,sum(if(name = 'yuwen',score,0)) chinese,sum(if(name = 'shuxue',score,0)) math,sum(if(name = 'yingyu',score,0)) english FROM zuoye1 group by id)select id from t1 where math>english""").show()# 关闭spark.stop()

运行结果：

二、查询每种爱好中年龄最大的人，如果有相同的年龄，并列显示。

数据

id;name;age;favor
1;huangbo;33;a,b,c,d,e
2;xuzheng;44;b,c
3;wangbaoqiang;33;c,d,e
4;fanbingbing;32;a,b,d

基本步骤： 

• 把favor列用炸裂函数explode炸开
• 用排名函数进行排序，根据题意相同年龄要并列显示，故选用rank()
• 用where筛选出排名第一的人

SQL代码： 

with t1 as(select name,age,aihao from zuoye2 lateral view explode(split(favor,',')) t1 as aihao),t2 as(select aihao,name,rank() over(partition by aihao order by age) r1 from t1)select * from t2 where r1 = 1 order by aihao

sparkSQL代码：

import os
import refrom pyspark.sql import SparkSession"""
------------------------------------------Description : TODO：SourceFile : _04-zuoye1Author  : zxxDate  : 2024/11/4
-------------------------------------------
"""
# 查询每种爱好中年龄最大的人，如果有相同的年龄，并列显示。
if __name__ == '__main__':os.environ['JAVA_HOME'] = 'D:/bigdata/03-java/java-8/jdk'# 配置Hadoop的路径，就是前面解压的那个路径os.environ['HADOOP_HOME'] = 'D:/bigdata/04-Hadoop/hadoop/hadoop-3.3.1/hadoop-3.3.1'# 配置base环境Python解析器的路径os.environ['PYSPARK_PYTHON'] = 'D:/bigdata/22-spark/Miniconda3/python.exe'  # 配置base环境Python解析器的路径os.environ['PYSPARK_DRIVER_PYTHON'] = 'D:/bigdata/22-spark/Miniconda3/python.exe'spark = SparkSession.builder.master("local[2]").appName("第一次构建SparkSession").config("spark.sql.shuffle.partitions", 2).getOrCreate()df = (spark.sparkContext.textFile("../../datas/zuoye2/zuoye2.txt").filter(lambda x:re.split(";",x)[0] !="id").map(lambda line: (re.split(";",line)[0],re.split(";",line)[1],re.split(";",line)[2],re.split(";",line)[3])).toDF(["id","name","age","favor"]))df.createOrReplaceTempView("zuoye2")spark.sql("""with t1 as(select name,age,aihao from zuoye2 lateral view explode(split(favor,',')) t1 as aihao),t2 as(select aihao,name,rank() over(partition by aihao order by age) r1 from t1)select * from t2 where r1 = 1 order by aihao""").show()# 关闭spark.stop()

运行结果：