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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 · Using a subquery in an UPDATE statement can be a good way to improve the maintainability of your queries. It can also reduce the number of steps required to update your data by compressing two or more queries into a single query.
30 Ιουλ 2020 · Since subqueries are used most often in SELECT statements, we will review an example of a simple subquery in a SELECT statement. We can define a subquery as a query within another query.
Introduction to the Oracle subquery. 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.
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. Sample Data. First, let’s set up some sample tables: -- Create and populate the departments table. CREATE TABLE departments (
5 Δεκ 2014 · 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. Below I get multiple values that come back from the select statement but I think my syntax is incorrect below.
