[
https://issues.apache.org/jira/browse/FLINK-5653?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15891752#comment-15891752
]
ASF GitHub Bot commented on FLINK-5653:
---------------------------------------
Github user huawei-flink commented on a diff in the pull request:
https://github.com/apache/flink/pull/3443#discussion_r103865652
--- Diff:
flink-libraries/flink-table/src/main/java/org/apache/flink/table/plan/logical/rel/util/WindowAggregateUtil.java
---
@@ -0,0 +1,103 @@
+/*
+ * 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.
+ */
+package org.apache.flink.table.plan.logical.rel.util;
+
+import java.io.Serializable;
+import java.util.List;
+
+import org.apache.calcite.rel.core.Window.Group;
+import org.apache.calcite.rel.logical.LogicalWindow;
+import org.apache.calcite.rex.RexLiteral;
+
+import com.google.common.collect.ImmutableList;
+
+public class WindowAggregateUtil implements Serializable {
+
+ private static final long serialVersionUID = -3916551736243544540L;
+
+ private LogicalWindow windowPointer = null;
+
+ public WindowAggregateUtil() {
+
+ }
+
+ public WindowAggregateUtil(LogicalWindow window) {
+ this.windowPointer = window;
+
+ }
+
+ /**
+ * A utility function that checks whether a window is partitioned or it
is a
+ * global window.
+ *
+ * @param LogicalWindow
+ * window to be checked for partitions
+ * @return true if partition keys are defined, false otherwise.
+ */
+ public boolean isStreamPartitioned(LogicalWindow window) {
+ // if it exists a group bounded by keys, the it is
+ // a partitioned window
+ for (Group group : window.groups) {
+ if (!group.keys.isEmpty()) {
+ return true;
+ }
+ }
+
+ return false;
+ }
+
+ public int[] getKeysAsArray(Group group) {
+ if (group == null) {
+ return null;
+ }
+ return group.keys.toArray();
+ }
+
+ /**
+ * This method returns the [[int]] lowerbound of a window when expressed
+ * with an integer e.g. ... ROWS BETWEEN [[value]] PRECEDING AND
CURRENT ROW
+ *
+ * @param constants
+ * the list of constant to get the offset value
+ * @return return the value of the lowerbound if available -1 otherwise
+ */
+
+ public int getLowerBoundary(ImmutableList<RexLiteral> constants) {
+ return ((Long)constants.get(0).getValue2()).intValue();
--- End diff --
Thank you very much. I was indeed puzzled by this. I will fix it according
to your suggestion. I even tried to get to the Calcite mailing list, but
nothing like this came out.
> Add processing time OVER ROWS BETWEEN x PRECEDING aggregation to SQL
> --------------------------------------------------------------------
>
> Key: FLINK-5653
> URL: https://issues.apache.org/jira/browse/FLINK-5653
> Project: Flink
> Issue Type: Sub-task
> Components: Table API & SQL
> Reporter: Fabian Hueske
> Assignee: Stefano Bortoli
>
> The goal of this issue is to add support for OVER ROWS aggregations on
> processing time streams to the SQL interface.
> Queries similar to the following should be supported:
> {code}
> SELECT
> a,
> SUM(b) OVER (PARTITION BY c ORDER BY procTime() ROWS BETWEEN 2 PRECEDING
> AND CURRENT ROW) AS sumB,
> MIN(b) OVER (PARTITION BY c ORDER BY procTime() ROWS BETWEEN 2 PRECEDING
> AND CURRENT ROW) AS minB
> FROM myStream
> {code}
> The following restrictions should initially apply:
> - All OVER clauses in the same SELECT clause must be exactly the same.
> - The PARTITION BY clause is optional (no partitioning results in single
> threaded execution).
> - The ORDER BY clause may only have procTime() as parameter. procTime() is a
> parameterless scalar function that just indicates processing time mode.
> - UNBOUNDED PRECEDING is not supported (see FLINK-5656)
> - FOLLOWING is not supported.
> The restrictions will be resolved in follow up issues. If we find that some
> of the restrictions are trivial to address, we can add the functionality in
> this issue as well.
> This issue includes:
> - Design of the DataStream operator to compute OVER ROW aggregates
> - Translation from Calcite's RelNode representation (LogicalProject with
> RexOver expression).
--
This message was sent by Atlassian JIRA
(v6.3.15#6346)
