SQL Learning 💻

When assigning unique identifiers to rows based on a specified order, three key functions come into play: ROW_NUMBER, RANK, and DENSE_RANK. Consider the following table: | Name | Score | |-------- |-------| | Alice | 90 | | Bob | 90 | | Carol | 85 | | David | 78 | ROW_NUMBER: The simplest of the three, ROW_NUMBER assigns a unique number to each row based on the specified order. Each row receives a distinct identifier, incrementing by one. Example:

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RANK: Assigns unique numbers, and in the case of ties, rows get the same rank, and the next rank is skipped.

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DENSE_RANK: Assigns ranks to rows with tied values, without skipping the next rank

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These functions help in organizing and analyzing data by providing distinct identifiers or ranks based on specified criteria. The example table illustrates how ROW_NUMBER, RANK, and DENSE_RANK operate in assigning order to rows with varying scores. (Note: This is 1/3 of the total number of articles; others are coming soon.)