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36 lines
1.1 KiB
C++
36 lines
1.1 KiB
C++
#pragma once
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#include <Parsers/IAST.h>
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#include <Interpreters/InDepthNodeVisitor.h>
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namespace DB
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{
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///
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/// Remove outer braces in ORDER BY
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/// For example, rewrite (1) to (2)
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/// (1) ... ORDER BY (a, b)
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/// │ ExpressionList (children 1) │
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/// │ OrderByElement (children 1) │
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/// │ Function tuple (children 1) │
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/// │ ExpressionList (children 2) │
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/// │ Identifier CounterID │
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/// │ Identifier EventDate │
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/// (2) ... ORDER BY a,b
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/// │ ExpressionList (children 2) │
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/// │ OrderByElement (children 1) │
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/// │ Identifier CounterID │
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/// │ OrderByElement (children 1) │
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/// │ Identifier EventDate │
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///
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class RewriteOrderBy
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{
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public:
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struct Data {};
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static void visit(ASTPtr & ast, Data &);
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static bool needChildVisit(const ASTPtr &, const ASTPtr &) { return true; }
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};
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using RewriteOrderByVisitor = InDepthNodeVisitor<RewriteOrderBy, true>;
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}
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