wutiangan commented on a change in pull request #3886:
URL: https://github.com/apache/incubator-doris/pull/3886#discussion_r440596171
##########
File path: fe/src/main/java/org/apache/doris/planner/DistributedPlanner.java
##########
@@ -294,6 +294,11 @@ private PlanFragment createHashJoinFragment(HashJoinNode
node, PlanFragment righ
// broadcast: send the rightChildFragment's output to each node
executing
// the leftChildFragment; the cost across all nodes is proportional to
the
// total amount of data sent
+
+ // NOTICE(cmy): for now, only MysqlScanNode and OlapScanNode has
Cardinality. And MysqlScanNode's Cardinality
+ // is always 0. Other ScanNode's cardinality is -1, so they won't be
able the calculate the cost of
Review comment:
```suggestion
// is always -1. Other ScanNode's cardinality is greater than or
equal 1, so they won't be able to calculate the cost of
```
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscr...@doris.apache.org
For additional commands, e-mail: commits-h...@doris.apache.org
