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Igor Nikonov 2024-12-10 19:35:48 +00:00
parent 2c4a0dd4c1
commit 457bb20d28
1 changed files with 10 additions and 7 deletions
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17
src/Planner/PlannerJoinTree.cpp
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@ -2014,20 +2014,23 @@ JoinTreeQueryPlan buildJoinTreeQueryPlan(const QueryTreeNodePtr & query_node,
if (joins_count > 1 && is_full_join) if (joins_count > 1 && is_full_join)
planner_context->getMutableQueryContext()->setSetting("enable_parallel_replicas", Field{0}); planner_context->getMutableQueryContext()->setSetting("enable_parallel_replicas", Field{0});
/** If left most table expression query plan is planned to stage that is not equal to fetch columns, // in case of n-way JOINs the table expression stack contains several join nodes
* then left most table expression is responsible for providing valid JOIN TREE part of final query plan. // so, we need to find right parent node for a table expression to pass into buildQueryPlanForTableExpression()
*
* Examples: Distributed, LiveView, Merge storages.
*/
// find parent node in the table expressions stack
QueryTreeNodePtr parent_join_tree = join_tree_node; QueryTreeNodePtr parent_join_tree = join_tree_node;
for (const auto & node : table_expressions_stack) for (const auto & node : table_expressions_stack)
{
if (node->getNodeType() == QueryTreeNodeType::JOIN || node->getNodeType() == QueryTreeNodeType::ARRAY_JOIN) if (node->getNodeType() == QueryTreeNodeType::JOIN || node->getNodeType() == QueryTreeNodeType::ARRAY_JOIN)
{ {
parent_join_tree = node; parent_join_tree = node;
break; break;
} }
}
/** If left most table expression query plan is planned to stage that is not equal to fetch columns,
* then left most table expression is responsible for providing valid JOIN TREE part of final query plan.
*
* Examples: Distributed, LiveView, Merge storages.
*/
auto left_table_expression = table_expressions_stack.front(); auto left_table_expression = table_expressions_stack.front();
auto left_table_expression_query_plan = buildQueryPlanForTableExpression( auto left_table_expression_query_plan = buildQueryPlanForTableExpression(
left_table_expression, left_table_expression,
@ -2102,7 +2105,7 @@ JoinTreeQueryPlan buildJoinTreeQueryPlan(const QueryTreeNodePtr & query_node,
continue; continue;
} }
// find parent node // find parent join node
parent_join_tree.reset(); parent_join_tree.reset();
for (size_t j = i + 1; j < table_expressions_stack.size(); ++j) for (size_t j = i + 1; j < table_expressions_stack.size(); ++j)
{ {