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This article is about how merge rewrites update. The editor thinks it is very practical, so share it with you as a reference and follow the editor to have a look.

1.OLD:

It is required to synchronize the data_object_id in HH2 to HH.

UPDATE HH A SET DATA_OBJECT_ID = (SELECT DATA_OBJECT_ID FROM HH2 B WHERE A.object_id = B.object_id) WHERE EXISTS (SELECT 1 FROM HH2 B WHERE A.object_id = B.object_id)

two。 Direction of optimization:

Use merge rewriting to reduce the number of visits to HH2

MERGE INTO HH A USING HH2 B ON (A.object_id = B.object_id) WHEN MATCHEDTHEN UPDATE SET DATA_OBJECT_ID = b. Data object object ID; thank you for reading! This is the end of the article on "how to rewrite merge update". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, you can share it for more people to see!

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