Merge pull request #22763 from CurtizJ/fix-having-push-down

Fix pushdown of having

src/Interpreters/ActionsDAG.cpp

@@ -1349,7 +1349,7 @@ ColumnsWithTypeAndName prepareFunctionArguments(const ActionsDAG::NodeRawConstPt
 /// Create actions which calculate conjunction of selected nodes.
 /// Assume conjunction nodes are predicates (and may be used as arguments of function AND).
 ///
-/// Result actions add single column with conjunction result (it is always last in index).
+/// Result actions add single column with conjunction result (it is always first in index).
 /// No other columns are added or removed.
 ActionsDAGPtr ActionsDAG::cloneActionsForConjunction(NodeRawConstPtrs conjunction, const ColumnsWithTypeAndName & all_inputs)
 {
@@ -1414,6 +1414,20 @@ ActionsDAGPtr ActionsDAG::cloneActionsForConjunction(NodeRawConstPtrs conjunctio
         }
     }
 
+    const Node * result_predicate = nodes_mapping[*conjunction.begin()];
+
+    if (conjunction.size() > 1)
+    {
+        NodeRawConstPtrs args;
+        args.reserve(conjunction.size());
+        for (const auto * predicate : conjunction)
+            args.emplace_back(nodes_mapping[predicate]);
+
+        result_predicate = &actions->addFunction(func_builder_and, std::move(args), {});
+    }
+
+    actions->index.push_back(result_predicate);
+
     for (const auto & col : all_inputs)
     {
         const Node * input;
@@ -1430,19 +1444,6 @@ ActionsDAGPtr ActionsDAG::cloneActionsForConjunction(NodeRawConstPtrs conjunctio
         actions->index.push_back(input);
     }
 
-    const Node * result_predicate = nodes_mapping[*conjunction.begin()];
-
-    if (conjunction.size() > 1)
-    {
-        NodeRawConstPtrs args;
-        args.reserve(conjunction.size());
-        for (const auto * predicate : conjunction)
-            args.emplace_back(nodes_mapping[predicate]);
-
-        result_predicate = &actions->addFunction(func_builder_and, std::move(args), {});
-    }
-
-    actions->index.push_back(result_predicate);
     return actions;
 }
 
@@ -1458,6 +1459,11 @@ ActionsDAGPtr ActionsDAG::cloneActionsForFilterPushDown(
                             "Index for ActionsDAG does not contain filter column name {}. DAG:\n{}",
                             filter_name, dumpDAG());
 
+    /// If condition is constant let's do nothing.
+    /// It means there is nothing to push down or optimization was already applied.
+    if (predicate->type == ActionType::COLUMN)
+        return nullptr;
+
     std::unordered_set<const Node *> allowed_nodes;
 
     /// Get input nodes from available_inputs names.
@@ -1507,7 +1513,19 @@ ActionsDAGPtr ActionsDAG::cloneActionsForFilterPushDown(
             node.result_name = std::move(predicate->result_name);
             node.result_type = std::move(predicate->result_type);
             node.column = node.result_type->createColumnConst(0, 1);
-            *predicate = std::move(node);
+
+            if (predicate->type != ActionType::INPUT)
+                *predicate = std::move(node);
+            else
+            {
+                /// Special case. We cannot replace input to constant inplace.
+                /// Because we cannot affect inputs list for actions.
+                /// So we just add a new constant and update index.
+                const auto * new_predicate = &addNode(node);
+                for (auto & index_node : index)
+                    if (index_node == predicate)
+                        index_node = new_predicate;
+            }
         }
 
         removeUnusedActions(false);

src/Interpreters/ActionsDAG.h

@@ -220,7 +220,7 @@ public:
     /// Create actions which may calculate part of filter using only available_inputs.
     /// If nothing may be calculated, returns nullptr.
     /// Otherwise, return actions which inputs are from available_inputs.
-    /// Returned actions add single column which may be used for filter.
+    /// Returned actions add single column which may be used for filter. Added column will be the first one.
     /// Also, replace some nodes of current inputs to constant 1 in case they are filtered.
     ///
     /// @param all_inputs should contain inputs from previous step, which will be used for result actions.
@@ -231,9 +231,9 @@ public:
     /// Pushed condition: z > 0
     /// GROUP BY step will transform columns `x, y, z` -> `sum(x), y, z`
     /// If we just add filter step with actions `z -> z > 0` before GROUP BY,
-    /// columns will be transformed like `x, y, z` -> `z, z > 0, x, y` -(remove filter)-> `z, x, y`.
+    /// columns will be transformed like `x, y, z` -> `z > 0, z, x, y` -(remove filter)-> `z, x, y`.
     /// To avoid it, add inputs from `all_inputs` list,
-    /// so actions `x, y, z -> x, y, z, z > 0` -(remove filter)-> `x, y, z` will not change columns order.
+    /// so actions `x, y, z -> z > 0, x, y, z` -(remove filter)-> `x, y, z` will not change columns order.
     ActionsDAGPtr cloneActionsForFilterPushDown(
         const std::string & filter_name,
         bool can_remove_filter,

src/Processors/QueryPlan/Optimizations/filterPushDown.cpp

@@ -73,8 +73,8 @@ static size_t tryAddNewFilterStep(
     child_node->children.emplace_back(&node);
     /// Expression/Filter -> Aggregating -> Filter -> Something
 
-    /// New filter column is added to the end.
+    /// New filter column is the first one.
-    auto split_filter_column_name = (*split_filter->getIndex().rbegin())->result_name;
+    auto split_filter_column_name = (*split_filter->getIndex().begin())->result_name;
     node.step = std::make_unique<FilterStep>(
             node.children.at(0)->step->getOutputStream(),
             std::move(split_filter), std::move(split_filter_column_name), true);

tests/queries/0_stateless/01798_having_push_down.reference

@@ -0,0 +1,2 @@
+1	1	2
+1	\N

tests/queries/0_stateless/01798_having_push_down.sql

@@ -0,0 +1,17 @@
+DROP TABLE IF EXISTS t_having;
+
+CREATE TABLE t_having (c0 Int32, c1 UInt64) ENGINE = Memory;
+
+INSERT INTO t_having SELECT number, number FROM numbers(1000);
+
+SELECT sum(c0 = 0), min(c0 + 1), sum(c0 + 2) FROM t_having
+GROUP BY c0 HAVING c0 = 0
+SETTINGS enable_optimize_predicate_expression=0;
+
+SELECT c0 + -1, sum(intDivOrZero(intDivOrZero(NULL, NULL), '2'), intDivOrZero(10000000000., intDivOrZero(intDivOrZero(intDivOrZero(NULL, NULL), 10), NULL))) FROM t_having GROUP BY c0 = 2, c0 = 10, intDivOrZero(intDivOrZero(intDivOrZero(NULL, NULL), NULL), NULL), c0 HAVING c0 = 2 SETTINGS enable_optimize_predicate_expression = 0;
+
+SELECT sum(c0 + 257) FROM t_having GROUP BY c0 = -9223372036854775808, NULL, -2147483649, c0 HAVING c0 = -9223372036854775808 SETTINGS enable_optimize_predicate_expression = 0;
+
+SELECT c0 + -2, c0 + -9223372036854775807, c0 = NULL FROM t_having GROUP BY c0 = 0.9998999834060669, 1023, c0 HAVING c0 = 0.9998999834060669 SETTINGS enable_optimize_predicate_expression = 0;
+
+DROP TABLE t_having;