Merge pull request #43141 from kitaisreal/analyzer-join-with-constants-improvements

Analyzer improve JOIN with constants

src/Planner/PlannerJoinTree.cpp

@@ -227,7 +227,11 @@ QueryPlan buildQueryPlanForJoinNode(QueryTreeNodePtr join_tree_node,
     JoinClausesAndActions join_clauses_and_actions;
     JoinKind join_kind = join_node.getKind();
 
-    auto join_constant = tryExtractConstantFromJoinNode(join_tree_node);
+    std::optional<bool> join_constant;
+
+    if (join_node.getStrictness() == JoinStrictness::All)
+        join_constant = tryExtractConstantFromJoinNode(join_tree_node);
+
     if (join_constant)
     {
         /** If there is JOIN with always true constant, we transform it to cross.

src/Planner/PlannerJoins.cpp

@@ -20,6 +20,7 @@
 #include <Functions/FunctionsConversion.h>
 #include <Functions/CastOverloadResolver.h>
 
+#include <Analyzer/FunctionNode.h>
 #include <Analyzer/TableNode.h>
 #include <Analyzer/TableFunctionNode.h>
 #include <Analyzer/JoinNode.h>
@@ -76,6 +77,23 @@ void JoinClause::dump(WriteBuffer & buffer) const
 
     if (!right_filter_condition_nodes.empty())
         buffer << " right_condition_nodes: " + dump_dag_nodes(right_filter_condition_nodes);
+
+    if (!asof_conditions.empty())
+    {
+        buffer << " asof_conditions: ";
+        size_t asof_conditions_size = asof_conditions.size();
+
+        for (size_t i = 0; i < asof_conditions_size; ++i)
+        {
+            const auto & asof_condition = asof_conditions[i];
+
+            buffer << "key_index: " << asof_condition.key_index;
+            buffer << "inequality: " << toString(asof_condition.asof_inequality);
+
+            if (i + 1 != asof_conditions_size)
+                buffer << ',';
+        }
+    }
 }
 
 String JoinClause::dump() const
@@ -249,9 +267,7 @@ void buildJoinClause(ActionsDAGPtr join_expression_dag,
         join_node);
 
     if (!expression_side_optional)
-        throw Exception(ErrorCodes::INVALID_JOIN_ON_EXPRESSION,
-                "JOIN {} with constants is not supported",
-                join_node.formatASTForErrorMessage());
+        expression_side_optional = JoinTableSide::Right;
 
     auto expression_side = *expression_side_optional;
     join_clause.addCondition(expression_side, join_expressions_actions_node);
@@ -277,6 +293,22 @@ JoinClausesAndActions buildJoinClausesAndActions(const ColumnsWithTypeAndName &
     for (const auto & node : join_expression_actions_nodes)
         join_expression_dag_input_nodes.insert(&node);
 
+    auto * function_node = join_node.getJoinExpression()->as<FunctionNode>();
+    if (!function_node)
+        throw Exception(ErrorCodes::INVALID_JOIN_ON_EXPRESSION,
+            "JOIN {} join expression expected function",
+            join_node.formatASTForErrorMessage());
+
+    /** It is possible to have constant value in JOIN ON section, that we need to ignore during DAG construction.
+      * If we do not ignore it, this function will be replaced by underlying constant.
+      * For example ASOF JOIN does not support JOIN with constants, and we should process it like ordinary JOIN.
+      *
+      * Example: SELECT * FROM (SELECT 1 AS id, 1 AS value) AS t1 ASOF LEFT JOIN (SELECT 1 AS id, 1 AS value) AS t2
+      * ON (t1.id = t2.id) AND 1 != 1 AND (t1.value >= t1.value);
+      */
+    auto constant_value = function_node->getConstantValueOrNull();
+    function_node->performConstantFolding({});
+
     PlannerActionsVisitor join_expression_visitor(planner_context);
     auto join_expression_dag_node_raw_pointers = join_expression_visitor.visit(join_expression_actions, join_node.getJoinExpression());
     if (join_expression_dag_node_raw_pointers.size() != 1)
@@ -284,6 +316,8 @@ JoinClausesAndActions buildJoinClausesAndActions(const ColumnsWithTypeAndName &
             "JOIN {} ON clause contains multiple expressions",
             join_node.formatASTForErrorMessage());
 
+    function_node->performConstantFolding(std::move(constant_value));
+
     const auto * join_expressions_actions_root_node = join_expression_dag_node_raw_pointers[0];
     if (!join_expressions_actions_root_node->function)
         throw Exception(ErrorCodes::INVALID_JOIN_ON_EXPRESSION,

tests/queries/0_stateless/02479_analyzer_join_with_constants.reference

@@ -0,0 +1,15 @@
+1	1
+--
+--
+--
+1	2
+--
+1	1	1	1
+--
+1	1	0	0
+--
+0
+0
+0
+0
+0

tests/queries/0_stateless/02479_analyzer_join_with_constants.sql

@@ -0,0 +1,27 @@
+SET allow_experimental_analyzer = 1;
+
+SELECT * FROM (SELECT 1 AS id) AS t1 INNER JOIN (SELECT 1 AS id) AS t2 ON t1.id = t2.id AND 1;
+
+SELECT '--';
+
+SELECT * FROM (SELECT 1 AS id) AS t1 INNER JOIN (SELECT 2 AS id) AS t2 ON t1.id = t2.id AND 1;
+
+SELECT '--';
+
+SELECT * FROM (SELECT 1 AS id) AS t1 INNER JOIN (SELECT 1 AS id) AS t2 ON t1.id = t2.id AND 0;
+
+SELECT '--';
+
+SELECT * FROM (SELECT 1 AS id) AS t1 INNER JOIN (SELECT 2 AS id) AS t2 ON t1.id = t2.id OR 1;
+
+SELECT '--';
+
+SELECT * FROM (SELECT 1 AS id, 1 AS value) AS t1 ASOF LEFT JOIN (SELECT 1 AS id, 1 AS value) AS t2 ON (t1.id = t2.id) AND 1 == 1 AND (t1.value >= t2.value);
+
+SELECT '--';
+
+SELECT * FROM (SELECT 1 AS id, 1 AS value) AS t1 ASOF LEFT JOIN (SELECT 1 AS id, 1 AS value) AS t2 ON (t1.id = t2.id) AND 1 != 1 AND (t1.value >= t2.value);
+
+SELECT '--';
+
+SELECT b.dt FROM (SELECT NULL > NULL AS pk, 1 AS dt FROM numbers(5)) AS a ASOF LEFT JOIN (SELECT NULL AS pk, 1 AS dt) AS b ON (a.pk = b.pk) AND 1 != 1 AND (a.dt >= b.dt);