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https://issues.apache.org/jira/browse/CALCITE-6763?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17910798#comment-17910798
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Julian Hyde commented on CALCITE-6763:
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{quote}The initial size of the PriorityQueue is difficult to estimate and is 
currently set to 1, causing frequent resizing of the PriorityQueue.{quote}

I don't think that's true. 1 is the maximum size of the queue. Elements are not 
the best are immediately discarded. Your algorithm has the same time and memory 
complexity as the current algorithm.

> Optimize logic to select the tiles with the fewest rows 
> --------------------------------------------------------
>
>                 Key: CALCITE-6763
>                 URL: https://issues.apache.org/jira/browse/CALCITE-6763
>             Project: Calcite
>          Issue Type: Improvement
>          Components: core
>            Reporter: xiaochen.zhou
>            Priority: Minor
>              Labels: pull-request-available
>
> Our current logic using a PriorityQueue to select the tile with the fewest 
> rows when multiple tiles are available. However, there are several potential 
> issues:
> 1. The PriorityQueue stores all satisfiable tiles. When the number of tiles 
> is large, maintaining the heap structure during element insertion has a time 
> complexity of O(log n), which also increases memory usage.
> 2. The initial size of the PriorityQueue is difficult to estimate and is 
> currently set to 1, causing frequent resizing of the PriorityQueue.
> We can optimize the code by keeping only a single bestCandidate tile to 
> improve performance.



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