On Thu, Sep 12, 2024 at 2:41 AM Tatsuo Ishii <is...@postgresql.org> wrote: > > It seems you allow to use IGNORE NULLS for all window functions. If > the case, you should explicitely stat that in the docs. Otherwise > users will be confused because;
The latest version restricts it to lag, lead, first_value, last_value, and nth_value. We can extend it in a subsequent patch if there's demand? > I take a look at the patch and noticed that following functions have > no comments on what they are doing and what are the arguments. Please > look into other functions in nodeWindowAgg.c and add appropriate > comments to those functions. Latest version has more comments and should be in the standard coding style. > I also notice that you have an array in memory which records non-null > row positions in a partition. The position is represented in int64, > which means 1 entry consumes 8 bytes. If my understanding is correct, > the array continues to grow up to the partition size. Also the array > is created for each window function (is it really necessary?). I worry > about this because it might consume excessive memory for big > partitions. It's an int64 because it stores the abs_pos/mark_pos which are int64. Keeping an array for each function is needed for the mark optimization to work correctly.
0003-ignore-nulls.patch
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