Bug #99244 | bad performance in hash join because join with no join condition between tables | ||
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Submitted: | 14 Apr 2020 3:22 | Modified: | 21 Apr 2020 16:24 |
Reporter: | chunyang xu | Email Updates: | |
Status: | Verified | Impact on me: | |
Category: | MySQL Server: Optimizer | Severity: | S1 (Critical) |
Version: | 8.0.19 | OS: | Any |
Assigned to: | CPU Architecture: | Any | |
Tags: | bad performance, Cartesian Product temp result., hash join |
If the data you need to attach is more than 50MB, you should create a compressed archive of the data, split it to 50MB chunks, and upload each of them as a separate attachment.
To split a large file:
- On *nix platforms use the split command e.g.
split -b 50MB <my_large_archive> <my_split_archive_prefix>
- On windows use WinZip or a similar utility to split the large file
[21 Apr 2020 16:46]
Shane Bester
[21 Apr 2020 17:23]
Shane Bester
what the "perf" looks like for the explain analyze and select queries
Attachment: perf_profile_8.0.19.txt (text/plain), 18.31 KiB.