Existential Quantification in XQuery

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Existential Quantification in XQuery

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Last edited Jul 29, 2017

Created on Jul 29, 2017

Two XQuery expressions demonstrate existential and universal quantification over a list of author names. The first uses `every ... satisfies` to test whether all names lack a period, while the second uses `some ... satisfies` to check if at least one contains a period. Both queries evaluate against four string literals, showing how XQuery’s quantified expressions return boolean results. The embedded visual likely contrasts the two outcomes with a simple layout, though no charting library appears in the code snippets.

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