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Sometimes when adding rows to your database need update-if-exists, insert-if-not-exists logic. Aka an upsert.
You could write this as separate update and insert statements. But there is an easier way:
Merge!
Watch this video for an overview of how merge works.
Further reading:
Merge documentation: docs.oracle.co...
Delete rows not in the source using merge: technology.ami...
Take the course: devgym.oracle....
Need help with SQL? Ask us over on AskTOM: asktom.oracle.com
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Daily SQL Twitter tips: / sqldaily
All Things SQL blog: blogs.oracle.c...
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The Magic of SQL with Chris Saxon
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