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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.
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.
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.
4 Αυγ 2024 · Ever found yourself needing to update a bunch of rows in your database, but the condition for the update depends on data from another table? That’s where UPDATE with a subquery comes in handy. Let’s break it down.
18 Νοε 2021 · SQL subqueries are basic tools if you want to communicate effectively with relational databases. In this article, I provide five subquery examples demonstrating how to use scalar, multirow, and correlated subqueries in the WHERE, FROM/JOIN, and SELECT clauses. A subquery, or nested query, is a query placed within another SQL query.
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.
5 Δεκ 2014 · using update query with subquery in Oracle sql - Database Administrators Stack Exchange. Ask Question. Asked 9 years, 10 months ago. Modified 8 years, 2 months ago. Viewed 1k times. 0. I have an update query where I am trying to update a field but for more than one record, I am trying a join but it doesn't work.
