https://realtimesupernal628.weebly.com/windows-default-key-generation-algorithm-calg-md5.html. Description: When INSERT. ON DUPLICATE KEY statements on InnoDB tables increment the auto-increment counter when a unique key value is matched and the. Replication: When events generated by one MySQL server instance were written to the binary log of another instance, the second server implicitly assumed that the first server supported the same number of binary log event types as itself. Where this was not the case, the event header was handled incorrectly. Page generated in 0.023 sec. https://realtimesupernal628.weebly.com/key-generation-algorithms-in-cryptography.html. Using MySQL 8.0.18-commercial Content reproduced on this site is the property of the respective copyright holders. It is not reviewed in advance by Oracle and does not necessarily represent the opinion of Oracle or any other party. Nov 22, 2013 It means that all code after ON DUPLICATE KEY UPDATE won't be executed. For instance in our example when we don't have such values in database, after this query we will have row with articleid = 12 and viewscount = 1 (not 2). https://realtimesupernal628.weebly.com/generate-a-new-public-key-based-on-rsa.html. Batch insert with ON DUPLICATE KEY. There is also option to make batch insert to database using ON DUPLICATE KEY UPDATE.
Posted by: David Jones
Date: March 31, 2009 02:43PM
I have a table containing two columns: id, tag 'id' is not unique .. a value can be repeated, each with a different 'tag'. 'tag' is not unique, in the same way. However, I never want have a duplicate entry for a given id,tag pair. I want to insert a new id1,tag1 pair, but only if it is not a duplicate. Should the following work? INSERT table SET id=id1, tag=tag1 ON DUPLICATE KEY UPDATE id=id I could say 'id' is the PRIMARY key (but it isn't unique), and I could make an INDEX on 'tag', .. but I don't know how to say that each 'id,tag' pair is unique .. so MySQL could recognize when there is a DUPLICATE. As a separate question, .. I can't figure out how to say 'ON DUPLICATE <DO NOTHING>', so that is why I put 'id=id'. I could first do a SELECT to see if the id1,tag1 pair is present in the table, and when it is not, I could do the INSERT, .. but this won't work when the MySQL database is at the back end of an active web site, with multiple interleaved queries happening all the time. Other updates could sneak in between my separate SELECT / INSERT queries. Any comments or suggestions appreciated, David Jones
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