What are some ways to improve MySQL performance on queries against large tables that include the HAVING BY clause. It's my understanding that anything in there doesn't benefit from table indexes.
Dani 4,084
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Jump to PostI'm not very familiar with HAVING but my understanding is that it is used to filter results after a GROUP operation so I can't imagine that indexes would improve performance other than on the original SELECT. Using WHERE would return rows based on one or more criteria, and would benefit …
Jump to PostPerhaps a smarter someone on this forum can help you look at the execution plan of your query and suggest some improvements.
Jump to PostI have a friend who spent the better part of a career doing SQL. I wrote up your question and sent it off to him. Just for sh!ts and giggles, he decided to feed it to ChatGPT first. He said that what he got back was what he would have …
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Reverend Jim 4,780
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Dani 4,084
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pritaeas 2,194
¯\_(ツ)_/¯ Moderator Featured Poster
Reverend Jim 4,780
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Dani
commented:
Keep It Clear: Do not post spun or AI-generated content -8
Dani 4,084
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Reverend Jim 4,780
Hi, I'm Jim, one of DaniWeb's moderators. Moderator Featured Poster
Reverend Jim 4,780
Hi, I'm Jim, one of DaniWeb's moderators. Moderator Featured Poster
Reverend Jim 4,780
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Dani
commented:
It did depend on GROUP. I spent hours and hours rewriting the query to be able to remove it. +34
Dani 4,084
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Dani 4,084
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Reverend Jim 4,780
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Dani 4,084
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Reverend Jim
commented:
Now you are just splitting hairs -3
AndreRet
commented:
Hence the quote and not posted as an answer... +0
Dani 4,084
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Reverend Jim
commented:
Works for me :-) +0
AndreRet 526
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Reverend Jim
commented:
Sorry to see you go. +15
Dani 4,084
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Reverend Jim 4,780
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Biiim 182
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Dani
commented:
Thank you for bringing this topic back on track! +34
Dani 4,084
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Reverend Jim 4,780
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Dani 4,084
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Dani 4,084
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Reverend Jim 4,780
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Dani 4,084
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Dani 4,084
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Reverend Jim 4,780
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Biiim 182
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