@@ -8894,7 +8894,7 @@ <h5>Grouping and Aggregation</h5>
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Replace V with Sample(V)
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End
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For each aggregate R(args ; scalarvals) now in X
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- # note scalarvals may be omitted, then it's equivalent to the empty function
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+ # note: scalarvals may be omitted; if so, it's equivalent to the empty function
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A<span><sub>i</sub></span> := Aggregation(args, R, scalarvals, Grp)
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Replace R(...) with agg<span><sub>i</sub></span> in Q
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i := i + 1
@@ -9554,13 +9554,13 @@ <h4>Aggregate Algebra</h4>
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<div id="defn_algAggregation">
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<b>Definition: Aggregation</b>
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</div>
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- <p>Let <i>exprlist</i> be a list of expressions or *, <i>func</i> a set function,
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- <i>scalarvals</i> a partial function (possibly with an empty domain) passed from the aggregate
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- in the query, and let { key<sub>1</sub>→Ψ<sub>1</sub>, ...,
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- key<sub>m</sub>→Ψ<sub>m</sub> } be a partial function from keys to
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+ <p>Let <i>exprlist</i> be a list of expressions or `*`; <i>func</i>, a set function;
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+ <i>scalarvals</i>, a partial function (possibly with an empty domain) passed from the aggregate
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+ in the query; and { key<sub>1</sub>→Ψ<sub>1</sub>, ...,
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+ key<sub>m</sub>→Ψ<sub>m</sub> }, a partial function from keys to
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solution sequences as produced by the grouping step.</p>
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- <p>Aggregation applies the set function func to the given set and produces a
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- single value for each key and group of solutions for that key.</p>
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+ <p>Aggregation applies the set function ` func` to the given set and produces a
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+ single value for each key and a group of solutions for that key.</p>
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<p>Aggregation(exprlist, func, scalarvals, { key<sub>1</sub>→Ψ<sub>1</sub>, ...,
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key<sub>m</sub>→Ψ<sub>m</sub> } )<br>
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= { (key, F(Ψ)) | key → Ψ in { key<sub>1</sub>→Ψ<sub>1</sub>, ...,
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