Mailing-List: contact issues-help@flink.apache.org; run by ezmlm
Precedence: bulk
Reply-To: dev@flink.apache.org
Date: Tue, 27 Dec 2016 11:15:58 +0000 (UTC)
From: "zhangjing (JIRA)" <jira@apache.org>
To: issues@flink.apache.org
Message-ID: <JIRA.13030674.1482836755000.599346.1482837358518@Atlassian.JIRA>
In-Reply-To: <JIRA.13030674.1482836755000@Atlassian.JIRA>
References: <JIRA.13030674.1482836755000@Atlassian.JIRA> <JIRA.13030674.1482836755142@arcas>
Subject: [jira] [Updated] (FLINK-5394) the estimateRowCount method of
 DataSetCalc didn't work
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
archived-at: Tue, 27 Dec 2016 11:16:00 -0000


     [ https://issues.apache.org/jira/browse/FLINK-5394?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

zhangjing updated FLINK-5394:
-----------------------------
    Description: 
The estimateRowCount method of DataSetCalc didn't work now. 
If I run the following code,
`
Table table = tableEnv
				.fromDataSet(data, "a, b, c")
				.groupBy("a")
				.select("a, a.avg, b.sum, c.count")
				.where("a == 1");
`
the cost of every node in Optimized node tree is :
`
DataSetAggregate(groupBy=[a], select=[a, AVG(a) AS TMP_0, SUM(b) AS TMP_1, COUNT(c) AS TMP_2]): rowcount = 1000.0, cumulative cost = {3000.0 rows, 5000.0 cpu, 28000.0 io}
  DataSetCalc(select=[a, b, c], where=[=(a, 1)]): rowcount = 1000.0, cumulative cost = {2000.0 rows, 2000.0 cpu, 0.0 io}
      DataSetScan(table=[[_DataSetTable_0]]): rowcount = 1000.0, cumulative cost = {1000.0 rows, 1000.0 cpu, 0.0 io}
`
We expect the input rowcount of DataSetAggregate less than 1000, however the actual input rowcount is still 1000 because the the estimateRowCount method of DataSetCalc didn't work. 

There are two reasons caused to this:
1. Didn't provide custom metadataProvider yet. So when DataSetAggregate calls RelMetadataQuery.getRowCount(DataSetCalc) to estimate its input rowcount which would dispatch to RelMdRowCount.
2. DataSetCalc is subclass of SingleRel. So previous function call would match getRowCount(SingleRel rel, RelMetadataQuery mq) which would never use DataSetCalc.estimateRowCount.

The question would also appear to all Flink RelNodes which are subclass of SingleRel.

I plan to resolve this problem by adding a FlinkRelMdRowCount which contains specific getRowCount of Flink RelNodes.

  was:
The estimateRowCount method of DataSetCalc didn't work now. 
If I run the following code,
`
Table table = tableEnv
				.fromDataSet(data, "a, b, c")
				.groupBy("a")
				.select("a, a.avg, b.sum, c.count")
				.where("a == 1");
`
the cost of every node in Optimized node tree is :
`
DataSetAggregate(groupBy=[a], select=[a, AVG(a) AS TMP_0, SUM(b) AS TMP_1, COUNT(c) AS TMP_2]): rowcount = 1000.0, cumulative cost = {3000.0 rows, 5000.0 cpu, 28000.0 io}
  DataSetCalc(select=[a, b, c], where=[=(a, 1)]): rowcount = 1000.0, cumulative cost = {2000.0 rows, 2000.0 cpu, 0.0 io}
      DataSetScan(table=[[_DataSetTable_0]]): rowcount = 1000.0, cumulative cost = {1000.0 rows, 1000.0 cpu, 0.0 io}
`
We expect the input rowcount of DataSetAggregate less than 1000, however the actual input rowcount is still 1000 because the the estimateRowCount method of DataSetCalc didn't work. 

There are two reasons caused to this:
1. Didn't provide custom metadataProvider yet. So when DataSetAggregate calls RelMetadataQuery.getRowCount(DataSetCalc) to estimate its input rowcount which would dispatch to RelMdRowCount.
2. DataSetCalc is subclass of SingleRel. So previous function call would match getRowCount(SingleRel rel, RelMetadataQuery mq) which would never use DataSetCalc.estimateRowCount.

I plan to resolve this problem by adding a FlinkRelMdRowCount which contains specific getRowCount of Flink RelNodes.


> the estimateRowCount method of DataSetCalc didn't work
> ------------------------------------------------------
>
>                 Key: FLINK-5394
>                 URL: https://issues.apache.org/jira/browse/FLINK-5394
>             Project: Flink
>          Issue Type: Bug
>          Components: Table API & SQL
>            Reporter: zhangjing
>            Assignee: zhangjing
>
> The estimateRowCount method of DataSetCalc didn't work now. 
> If I run the following code,
> `
> Table table = tableEnv
> 				.fromDataSet(data, "a, b, c")
> 				.groupBy("a")
> 				.select("a, a.avg, b.sum, c.count")
> 				.where("a == 1");
> `
> the cost of every node in Optimized node tree is :
> `
> DataSetAggregate(groupBy=[a], select=[a, AVG(a) AS TMP_0, SUM(b) AS TMP_1, COUNT(c) AS TMP_2]): rowcount = 1000.0, cumulative cost = {3000.0 rows, 5000.0 cpu, 28000.0 io}
>   DataSetCalc(select=[a, b, c], where=[=(a, 1)]): rowcount = 1000.0, cumulative cost = {2000.0 rows, 2000.0 cpu, 0.0 io}
>       DataSetScan(table=[[_DataSetTable_0]]): rowcount = 1000.0, cumulative cost = {1000.0 rows, 1000.0 cpu, 0.0 io}
> `
> We expect the input rowcount of DataSetAggregate less than 1000, however the actual input rowcount is still 1000 because the the estimateRowCount method of DataSetCalc didn't work. 
> There are two reasons caused to this:
> 1. Didn't provide custom metadataProvider yet. So when DataSetAggregate calls RelMetadataQuery.getRowCount(DataSetCalc) to estimate its input rowcount which would dispatch to RelMdRowCount.
> 2. DataSetCalc is subclass of SingleRel. So previous function call would match getRowCount(SingleRel rel, RelMetadataQuery mq) which would never use DataSetCalc.estimateRowCount.
> The question would also appear to all Flink RelNodes which are subclass of SingleRel.
> I plan to resolve this problem by adding a FlinkRelMdRowCount which contains specific getRowCount of Flink RelNodes.


--
This message was sent by Atlassian JIRA
(v6.3.4#6332)