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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

Unix Special Keys That Improve Productivity

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Shared the UNIX terminal shortcut keys. These special keys you can use to stop the program processing, or resume it. An example of a UNIX special key and its use. Special Keys in UNIX much useful to take action when something happens. A scenario where you made some mistake in the input command and you need to stop the further process. Then you can use the CTRL+C command. It is equal to the DELETE command. Unix Keyboard Shortcuts or Special Keys. RETURN key  The RETURN key signifies the end of a line of input. On any terminal, RETURN has a key of its own, or return may be typed by holding down the control key and typing a 'm'. CTRL-m Key Hint: Ctrl-m command is equal to RETURN key in Unix systems DELETE Key The DELETE key stops a program/command immediately, without waiting for it to finish. DELETE can be achieved equivalently with ctrl-c. Hint: Ctrl-c Command you can use to interrupt the process. CTRL-s Key Ctrl-s pauses the output and the program is suspended until you sta