*** 27,32 **** --- 27,34 ---- Perform ranking queries - Show the relative rank of an individual's salary within their department. + *: Both the "Top-N" and ranking queries could perhaps be implemented by simply having a result row number be returned (after sorting). The row number can then be used to calculate positional-based info. It would be similar to Oracle's "rownum" pseudo-column, but without the limits of Oracle's take. + Analytic functions, are designed to address these issues. They add extensions to the SQL language that not only make these operations easier to code; they make them faster than could *************** *** 39,45 **** but looks can be deceiving. It starts with: ! FUNCTION_NAME(<argument>,<argument>,) OVER (<Partition-Clause> <Order-by-Clause> <Windowing Clause>) --- 41,47 ---- but looks can be deceiving. It starts with: ! FUNCTION_NAME(<argument>,<argument>,?) OVER (<Partition-Clause> <Order-by-Clause> <Windowing Clause>)
Small. Fast. Reliable.
Choose any three.
Choose any three.
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