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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.
10 Μαΐ 2012 · update tabl a. set (a.c1) = (select sum(c1) from ( select c1,a1,b1 from t1,t2,t3 where .. some joins)). This query need to be aliased so that I can check with the. table to be updated with the key values. update tabl a. set (a.c1) = (select sum(c1) from ( select c1,a1,b1 from t1,t2,t3 where .. some joins))qry.
Update using correlated subquery. This statement uses a correlated subquery to update a single column across multiple rows in the FLIGHTS table. It increases the duration of all BA flights by thirty minutes. The subquery returns all flights with OPERATING_CARRIER_CODE set to 'BA'. This result is used as the predicate value in the UPDATE statement.
Use the UPDATE statement to change existing values in a table or in the base table of a view or the master table of a materialized view. Prerequisites. For you to update values in a table, the table must be in your own schema or you must have the UPDATE object privilege on the table. For you to update values in the base table of a view:
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 ...
