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====================================
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Query execution
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====================================
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Usually, in a database,
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how queries are executed is usually considered an implementation detail
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hidden behind an abstraction layer, which normal users need not care about.
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As everyone knows, however, this abstraction layer is leaky,
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since bad query execution plans invariably occur and hurt performance,
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and developers routinely "go under" the abstraction layer to solve such problems.
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Therefore, in Cozo we take the pragmatic approach and make certain guarantees
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about query execution, which we will explain in the following.
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It is essential to at least have a rough idea of these guarantees to write
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efficient queries and to debug performance.
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--------------------------------------
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Stratification
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--------------------------------------
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--------------------------------------
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Semi-naïve evaluation
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--------------------------------------
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--------------------------------------
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Magic set rewrites
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--------------------------------------
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---------------------------------------
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Relations as indices
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Ordering of atoms
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Early stopping
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---------------------------------------
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