IGNITE-27976 Support OVER clause with unbounded frame

docs/_data/toc.yaml

@@ -238,6 +238,8 @@
       url: sql-reference/operational-commands
     - title: Aggregate functions
       url: sql-reference/aggregate-functions
+    - title: Window Functions
+      url: sql-reference/window-functions
     - title: Numeric Functions
       url: sql-reference/numeric-functions
     - title: String Functions

docs/_docs/sql-reference/window-functions.adoc

@@ -0,0 +1,27 @@
+// Licensed to the Apache Software Foundation (ASF) under one or more
+// contributor license agreements.  See the NOTICE file distributed with
+// this work for additional information regarding copyright ownership.
+// The ASF licenses this file to You under the Apache License, Version 2.0
+// (the "License"); you may not use this file except in compliance with
+// the License.  You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+= Window Functions
+
+Ignite supports aggregate functions in the window form only for the following syntax:
+
+[source,sql]
+----
+fun() OVER ([PARTITION BY <field> | <exp>])
+----
+
+The following constructs are not supported for window aggregates and will throw an exception:
+
+- `ORDER BY` inside the `OVER(...)` clause;
+- explicit window frame bounds (`ROWS`, `RANGE`, `BETWEEN ... AND ...`).

modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/prepare/PlannerHelper.java

@@ -117,6 +117,8 @@ public static IgniteRel optimize(SqlNode sqlNode, IgnitePlanner planner, IgniteL
             // Transformation chain
             rel = planner.transform(PlannerPhase.HEP_DECORRELATE, rel.getTraitSet(), rel);
 
+            rel = planner.transform(PlannerPhase.HEP_REWRITE_WINDOWS, rel.getTraitSet(), rel);
+
             // RelOptUtil#propagateRelHints(RelNode, equiv) may skip hints because current RelNode has no hints.
             // Or if hints reside in a child nodes which are not inputs of the current node. Like LogicalFlter#condition.
             // Such hints may appear or be required below in the tree, after rules applying.

modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/prepare/PlannerPhase.java

@@ -72,6 +72,7 @@
 import org.apache.ignite.internal.processors.query.calcite.rule.ValuesConverterRule;
 import org.apache.ignite.internal.processors.query.calcite.rule.logical.ExposeIndexRule;
 import org.apache.ignite.internal.processors.query.calcite.rule.logical.FilterScanMergeRule;
+import org.apache.ignite.internal.processors.query.calcite.rule.logical.IgniteLogicalWindowRewriteRule;
 import org.apache.ignite.internal.processors.query.calcite.rule.logical.IgniteMultiJoinOptimizeRule;
 import org.apache.ignite.internal.processors.query.calcite.rule.logical.LogicalOrToUnionRule;
 import org.apache.ignite.internal.processors.query.calcite.rule.logical.ProjectScanMergeRule;
@@ -102,6 +103,23 @@ public enum PlannerPhase {
         }
     },
 
+    /** */
+    HEP_REWRITE_WINDOWS("Heuristic phase to rewrite window functions") {
+        /** {@inheritDoc} */
+        @Override public RuleSet getRules(PlanningContext ctx) {
+            return ctx.rules(RuleSets.ofList(
+                    CoreRules.PROJECT_TO_LOGICAL_PROJECT_AND_WINDOW,
+                    IgniteLogicalWindowRewriteRule.INSTANCE
+                )
+            );
+        }
+
+        /** {@inheritDoc} */
+        @Override public Program getProgram(PlanningContext ctx) {
+            return hep(getRules(ctx));
+        }
+    },
+
     /** */
     HEP_FILTER_PUSH_DOWN("Heuristic phase to push down filters") {
         /** {@inheritDoc} */