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Updated implementation

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This commit is contained in:
Maksim Kita 2024-03-12 15:02:02 +03:00
parent 742a2f1043
commit 77a7d0027a
1 changed files with 17 additions and 8 deletions
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25
src/Processors/QueryPlan/Optimizations/filterPushDown.cpp
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@ -241,6 +241,8 @@ static size_t tryPushDownOverJoinStep(QueryPlan::Node * parent_node, QueryPlan::
* 2. TODO: Support building equivalent sets for JOINs with more than 1 clause.
* 3. TODO: For LEFT/RIGHT join support optimization, we can assume that RIGHT/LEFT columns used in filter will be default/NULL constants and
* check if filter will always be false, in those scenario we can transform LEFT/RIGHT JOIN into INNER JOIN and push conditions to both tables.
* 4. TODO: It is possible to pull up filter conditions from LEFT/RIGHT stream and push conditions that use only columns from equivalent sets
* to RIGHT/LEFT stream.
*/
const auto & left_stream_input_header = child->getInputStreams().front().header;
@ -311,20 +313,27 @@ static size_t tryPushDownOverJoinStep(QueryPlan::Node * parent_node, QueryPlan::
for (const auto & name : input_columns_names)
{
/// Skip columns that does not have equivalent column in other stream
if (!filter_push_down_all_input_columns_available && !equivalent_columns_for_filter.contains(name))
continue;
auto input_name = name;
/// Skip key if it is renamed.
/// I don't know if it is possible. Just in case.
if (!input_header.has(name) || !join_header.has(name))
/// Skip columns that does not have equivalent column in other stream
if (!filter_push_down_all_input_columns_available)
{
auto it = equivalent_columns_for_filter.find(name);
if (it == equivalent_columns_for_filter.end())
continue;
if (!join_header.has(input_name))
input_name = it->second.name;
}
if (!join_header.has(input_name))
continue;
/// Skip if type is changed. Push down expression expect equal types.
if (!input_header.getByName(name).type->equals(*join_header.getByName(name).type))
if (!input_header.getByName(input_name).type->equals(*join_header.getByName(input_name).type))
continue;
available_input_columns_for_filter.push_back(name);
available_input_columns_for_filter.push_back(input_name);
}
if (available_input_columns_for_filter.empty())