Merge is a good technique to updating values quickly . If you want to update values in a big table from a table(with only columns meant for update) , you may write the code like below…. PS -> If you have indexes created on the columns of match , the merge update will be faster. Now the code is …. Merge /*+ PARALLEL */ into <schema>.<table> t1 using (select col1 , col2 from <schema>.<table> ) t2 on t1.<join column > = t2.<join column>
