I have a table with 30M+ rows, and each index update is expensive. I sometimes have to update and/or add 5000+ rows in a single insert.开发者_如何学运维 Sometimes all rows are new, sometimes some are new.
I cannot use update - since I don't know which is already in the table, so I use INSERT .. ON DUPLICATE KEY UPDATE for a single column.
This sometimes take a lot of time >5 sec.
Is there a better way to do it? maybe I did not explain myself clear enough :)
Are you issuing 5000+ separate insert statements? If so, lock the table while doing the inserts; it'll go a lot faster.
I added BEGIN TRANSACTION and COMMIT to perform the insert, and it enhanced performance by x4 to x10.
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