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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.
4 Αυγ 2023 · Direct join syntax is unsupported in Oracle Database; use a correlated subquery to fetch the values instead. For example: update nashvillehousing a set propertyaddress = ( select nvl2(a.propertyaddress, b.propertyaddress,b.propertyaddress) from nashvillehousing b where a.parcelid = b.parcelid and a.uniqueid_ != b.uniqueid_ ) where a ...
27 Δεκ 2023 · Before diving into complex examples, let's understand the basic syntax of an update with a join operation in Oracle: sql UPDATE table1 SET table1.target_column = (SELECT table2.source_column FROM table2 WHERE table1.join_column = table2.join_column) WHERE EXISTS (SELECT 1 FROM table2 WHERE table1.join_column = table2.join_column); In the abov...
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 ...
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.
