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If you want to update specific rows (ie where the IDs match) you probably want to do a coordinated subquery. However, since you are using Oracle, it might be easier to create a materialized view for your query table and let Oracle's transaction mechanism handle the details.
6 Δεκ 2017 · Learn about several methods to update data using subqueries in UPDATE statements to make them more effective and easier to maintain in Oracle SQL.
Subquery Method. The first option is to do an update of the DEST_TAB table using a subquery to pull the correct data from the SOURCE_TAB table. Notice the EXISTS predicate to exclude rows from the DEST_TAB table with no matching row in the SOURCE_TAB table.
24 Μαΐ 2017 · Usually, when you need to join multiple tables in an UPDATE, MERGE is the solution. merge into address a1 using ( select p.address_fk, ta2.tempaddress1 from premise p join account ac on (ac.id = p.account_fk) join tempaddresstable ta2 on (ac.ext_ref = ta2.tempextref) ) ta1 on (a1.id = ta1.address_fk) when matched then update set a1.address1 ...
This tutorial shows you how to use the Oracle subquery to construct more readable queries without using complex joins or unions.
table | view | materialized_view | subquery. Specify the name of the table, view, materialized view, or the columns returned by a subquery to be updated. Issuing an UPDATE statement against a table fires any UPDATE triggers associated with the table. If you specify view, then the database updates the base table of the view.
3 Μαΐ 2016 · Please pay attention on ( subquery ) part of the above syntax. The subquery is a feature that allows to perform an update of joins. In the most simplest form it can be: UPDATE ( subquery-with-a-join ) SET cola=colb Before update a join, you must know restrictions listed here: https://docs.oracle.com/cd/B28359_01/server.111/b28286/statements ...
