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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.
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 ...
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 ...
30 Μαΐ 2011 · From Oracle Database 23ai you can use direct joins in update to copy values from one table to another:
17 Απρ 2012 · If you need to use a subquery to perform the UPDATE you can do it this way: UPDATE t1 SET t1.value = t2.value FROM Table1 t1 JOIN ( SELECT id, value FROM table2 ) t2 ON t1.id = t2.id
