Problem description & analysis

Below is part of the CSV file books.csv:

"book_id","books_count","authors","original_publication_year","title","work_text_reviews_count","ratings_1","ratings_2","ratings_3","ratings_4","ratings_5","ratings_count","work_ratings_count","average_rating"

1,321,"author1",2013,"title1",81786,171184,194374,347116,148563,179728,1040965,1095481,2.82

2,399,"author2",2018,"title2",90118,184637,195711,325457,120472,153599,979876,988025,2.84

3,269,"author3",2007,"title3",81776,155035,145240,308206,142679,168599,919759,977895,2.85

4,229,"author4",2016,"title4",116917,184987,159633,389774,119616,142820,996830,1038375,2.76

5,356,"author5",2001,"title5",117952,167016,102358,345956,148374,131290,894994,924198,2.88

...

Tasks:

1. List titles of all books whose ratings_5 values are greater than 150000.

2. List titles of all books whose reviews count are at least 100000 and whose 3-star rating occupies at least 40%.

Below are the desired results:

Task 1:

title1

title2

title3

title7

title8

…

Task 2:

title28

title33

title34

title39

title41

…

Solution

Write the following script p1.dfx in esProc:

	A
1	=file("books.csv").import@qct()
2	=A1.select(ratings_5>150000).(title)
3	=A1.select(reviews>100000 &&     ratings_3/ratings_count>0.4).(title)

Explanation:

A1  Import the CSV file, during which the first row is read as column headers.

A2  Find titles of all books that get more than 150000 5-star ratings.

A3  Find titles of all books whose reviews count are at least 100000 and whose 3-star rating occupies at least 40%.

Find how to integrate the script code into a Java program in How to Call an SPL Script in Java.

Q & A Collection

https://stackoverflow.com/questions/61187096/simplest-way-to-read-csv-file-of-10000-lines-in-java-and-list-items-based-on-cer