Sams Teach Yourself SQL in 21 Days, Fourth Edition

Q&A

Q1:	If I streamline my SQL statement, how much of a gain in performance should I expect?
A1:	Performance gain depends on the size of your tables, whether columns in the table are indexed, and other relative factors. In a very large database, a complex query that runs for hours can sometimes be cut to minutes. In the case of transactional processing, streamlining a SQL statement can save important seconds for the end user.
Q2:	How do I coordinate my batch loads or updates?
A2:	Check with the database administrator and, of course, with management when scheduling a batch load or update. If you are a system engineer, you probably will not know everything that is going on within the database.
Q3:	How often should I commit my batch transactions?
A3: ...