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SQL Query: 3 Methods for Calculating Cumulative SUM

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SQL provides various constructs for calculating cumulative sums, offering flexibility and efficiency in data analysis. In this article, we explore three distinct SQL queries that facilitate the computation of cumulative sums. Each query leverages different SQL constructs to achieve the desired outcome, catering to diverse analytical needs and preferences. Using Window Functions (e.g., PostgreSQL, SQL Server, Oracle) SELECT id, value, SUM(value) OVER (ORDER BY id) AS cumulative_sum  FROM your_table; This query uses the SUM() window function with the OVER clause to calculate the cumulative sum of the value column ordered by the id column. Using Subqueries (e.g., MySQL, SQLite): SELECT t1.id, t1.value, SUM(t2.value) AS cumulative_sum FROM your_table t1 JOIN your_table t2 ON t1.id >= t2.id GROUP BY t1.id, t1.value ORDER BY t1.id; This query uses a self-join to calculate the cumulative sum. It joins the table with itself, matching rows where the id in the first table is greater than or

Daily use AWS File Commands

The AWS Command Line Interface (CLI) is a unified tool to manage your AWS services. With just one tool to download and configure, you can control multiple AWS services from the command line and automate them through scripts.

The AWS CLI introduces a new set of simple file commands for efficient file transfers to and from Amazon S3.
Daily use AWS file commands
Daily use AWS file commands

$ aws ec2 describe-instances


$ aws ec2 start-instances --instance-ids i-1348636c


$ aws sns publish --topic-arn arn:aws:sns:us-east-1:546419318123:OperationsError --message "Script Failure"


$ aws sqs receive-message --queue-url https://queue.amazonaws.com/546419318123/Test


$ aws help

$ aws autoscaling help

$ aws autoscaling create-auto-scaling-group help

$ aws s3 ls s3://mybucket

        LastWriteTime            Length Name

        ------------             ------ ----

                                            PRE myfolder/

2013-09-03 10:00:00           1234 myfile.txt



Sync command:
$ aws s3 sync myfolder s3://mybucket/myfolder --exclude *.tmp
upload: myfolder/newfile.txt to s3://mybucket/myfolder/newfile.txt


Read more here.

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