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This commit is contained in:
Artem Zuikov 2020-03-20 15:21:02 +03:00
parent b6d2895511
commit b0d54e474b
1 changed files with 1 additions and 1 deletions
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dbms/src/Interpreters/JoinToSubqueryTransformVisitor.cpp
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@ -655,7 +655,7 @@ void JoinToSubqueryTransformMatcher::visit(ASTPtr & ast, Data & data)
/// 1. Expand asterisks in select expression list.
/// 2. Normalize column names and find name clashes
/// 3. Rewrite multiple JOINs with subqueries:
/// SELECT ... FROM (SELECT `--join`.*, ... FROM (...) AS `--join` JOIN tableY ON ...) AS `--join` JOIN tableZ ON ...'
/// SELECT ... FROM (SELECT `--.s`.*, ... FROM (...) AS `--.s` JOIN tableY ON ...) AS `--.s` JOIN tableZ ON ...'
/// 4. Push down expressions of aliases used in ON section into expression list of first reletad subquery
void JoinToSubqueryTransformMatcher::visitV2(ASTSelectQuery & select, ASTPtr & ast, Data & data)
{