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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.
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.
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.
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.
1 Μαΐ 2012 · The ORA-01427 indicates you are returning more than one value in a subquery. Modify your query to contain a DISTINCT clause or some other mechanism to uniquely identify a row in the subquery. UPDATE table1. SET table1.fieldToChange =.
24 Μαΐ 2017 · Usually, when you need to join multiple tables in an UPDATE, MERGE is the solution.
