Performance issue. The issue was due to joins across remote sites where oracle optimizer might Wrongly choose the driving site. This can be resolved by using driving site hint. It is always good to do all manipulations in one site and fetch the final Results to the target site. QUERY EXCEUTED IN DATA BASE 2 Select t1.column1, t2.column2, t2.column3 From table1 t1, xxsc.table2@db1todb2 t2 Where t1.column1 = t2.column1 Query which was taking around 47 msecs for execution. QUERY EXCEUTED IN DATA BASE 2 Select /*+driving_site(t2)*/ t1.column1, t2.column2, t2.column3 From table1 t1, xxsc.table2@db1todb2 t2 Where t1.column1 = t2.column1 Query which was taking around 15 msecs for execution.
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