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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.
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.
A subquery is a SELECT statement nested inside another statement such as SELECT, INSERT, UPDATE, or DELETE. Typically, you can use a subquery anywhere that you use an expression. Consider this following subquery example that uses the products table from the sample database.
You may use subqueries in place of tables in this way as well in INSERT, UPDATE, and DELETE statements. Subqueries so used can employ correlation variables, both defined within the subquery itself and those defined in query blocks containing the 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.
