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8 Ways to Optimize AWS Glue Jobs in a Nutshell

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  Improving the performance of AWS Glue jobs involves several strategies that target different aspects of the ETL (Extract, Transform, Load) process. Here are some key practices. 1. Optimize Job Scripts Partitioning : Ensure your data is properly partitioned. Partitioning divides your data into manageable chunks, allowing parallel processing and reducing the amount of data scanned. Filtering : Apply pushdown predicates to filter data early in the ETL process, reducing the amount of data processed downstream. Compression : Use compressed file formats (e.g., Parquet, ORC) for your data sources and sinks. These formats not only reduce storage costs but also improve I/O performance. Optimize Transformations : Minimize the number of transformations and actions in your script. Combine transformations where possible and use DataFrame APIs which are optimized for performance. 2. Use Appropriate Data Formats Parquet and ORC : These columnar formats are efficient for storage and querying, signif
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How to Use List Function in Python

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Here's is an answer to calculate the length of the repeated lists. LIST is a principle data type in Python that holds a list of values. Usually strings.

List() Function the Real Usage

You can do various operations with Lists. The best examples are REPEAT, APPEND, INSERT, EXTEND, COUNT. Still more you can do.


Note: This question is from a test recently held by an HR company. HR firms usually ask to take an online test to filter the job-seekers.

You can find list length using list() and len() functions


IN THIS PAGE


1. Question
2. How to Find Length


Interview Question 

The '* 2' says times the list is repeated. In this question, they have given '2' times.


my_list = ['srini', 'seetha', 'rao']
b = len(list(list(list(list(list(my_list*2))))))
Print (b)


Select Answer

1. 5
2. 6
3. 7
4. None

Explanation:

  • In the first step, the '*' says, you repeated the List two times.
  • It confuses the test-taker since they have given multiple functions of the list().

How to get Length


You can code the way I did. So that you can get the length correctly. So, the answer to the question is '6'. The List is repeated twice. There's no effect of multiple lists on the list.


Result (Ubuntu Linux OS)


At the command level, the given question entered. After pressing enter, it showed the result as '6'. That means the list (which has initially '3' elements') doubled. So the list length is now '6'.


Result of Python List

References

  1. Here're the best examples on Python List
  2. Here's the complete list for your reference.

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