Hi, I'm joining 2 tables (each with over 400000 records). The join is made on 4 columns. Its returning rows more than what am expecting. Each record is present atleast twice even though there is no difference btw two rows... When I saw the execution plan, its showing parallelism (gather streams). What does this mean? It takes more than 3 minutes to execute a select statement. Am involved in doing data imports. I'm actually trying to update one table with the values from other table (which has imported data). The update seems to be running forever. Anyway to reduce it? Thanks.