removal_method

[jinghehehe]

What changes were proposed in this pull request?

add 1 aggregation method in window function: Removable Cumulative Aggregation.

Why are the changes needed?

when compute frame's aggregation value in window function, if interval is iteration interval, window function only use naive aggregation, we add removable cumulative aggregation for supporting iteration interval. However, the segment_tree method has limited application scenarios and restrictions. Therefore, we delete segment_tree method now.

Will break the compatibility? How if so?

No

Does this PR introduce any user-facing change?

No

How was this patch tested?

add test file: test/mysql_test/test_suite/window_function/t/removal.test add result file:test/mysql_test/test_suite/window_function/r/mysql/removal.result

Checklist

• [x] I've run the tests to see all new and existing tests pass.
• [x] If this Pull Request resolves an issue, I linked to the issue in the text above.
• [x] I've informed the technical writer about the documentation change if necessary.