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theGroupVars : For each grouping var X, theGroupVars contains a pair of
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exprs: the 1st element of the pair is a reference to X in
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the groupby's input tuple stream, and the 2nd element is
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a var_expr representing the variable gX that the groupby
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produces for X in its output tuple stream.
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theNonGroupVars : For each non-grouping var Y, theGroupVars contains a pair of
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exprs: the 1st element of the pair is a reference to Y in
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the groupby's input tuple stream, and the 2nd element is
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a var_expr representing the variable gY that the groupby
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produces for Y in its output tuple stream. For each tuple
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T produced by the groupby, gY is the concatenation of all
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the Y values in the input tuples that were grouped into T.
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theCollations : The collations to use when comparing values for grouping.
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For each grouping var X, theGroupVars contains a pair of exprs: the 1st
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element of the pair is the expr that computes the grouping keys for X;
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the 2nd element is a var_expr representing the variable gX that the groupby
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produces for X in its output tuple stream.
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For each non-grouping var Y, theNonGroupVars contains a pair of exprs: the
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1st element of the pair is a reference to Y in the groupby's input tuple
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stream, and the 2nd element is a var_expr representing the variable gY that
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the groupby produces for Y in its output tuple stream. For each tuple T
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produced by the groupby, gY is the concatenation of all the Y values in the
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input tuples that were grouped into T.
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The collations to use when comparing values for grouping.
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413
********************************************************************************/
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class groupby_clause : public flwor_clause
added
removed
src/compiler/expression/flwor_expr.h
