What are window function in sql ? SQL joins? CTE in sql?

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Accepted Answer

Window functions are used to perform calculations across a set of rows in a table.

Window functions operate on a subset of rows called a window or frame.
They can be used to calculate running totals, rankings, and moving averages.
Examples of window functions include ROW_NUMBER, RANK, and LAG.
SQL joins are used to combine rows from two or more tables based on a related column between them.
Common types of joins include INNER JOIN, LEFT JOIN, and RIGHT JOIN.
CTE (Common Table Expression) is a temporary named result set that can be referenced within a SELECT, INSERT, UPDATE, or DELETE statement.
CTEs are useful for breaking down complex queries into smaller, more manageable parts.
They can improve query readability and performance.
Example of CTE: WITH cte AS (SELECT * FROM table) SELECT * FROM cte

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