1.Use Views to Insulate Programs from Change
This lie has been told for almost as long as DB2 has been around. I first wrote about this way back in 1991 for Database Programming & Design. Check that article out here if you don't understand why this is a bad idea, in general.
2.Locking Problems Indicate a Database Problem
Locking problems are generally caused by bad program design. You should write code to reduce the duration of locks and to COMMIT regularly... and then locking won't be a problem, for the most part.
3.Primary Key is Usually a Good Choice for Clustering
Actually, the foreign key is likely to be a better choice. When you join PK-->FK there will be one PK to multiple FK. Wouldn't it be best if the FKs were clustered on the same page (or pages)?
4.Just Using the Defaults Should Work Out Well
Don't rely on defaults. Many of them are outdated or wrong... and even if they aren't it will be better if you review and investigate all options before explicitly specifying the parameter value you want.
5.Programmers Don’t Need to Know How to Tune SQL
Programming performance-oriented SQL into your programs from the beginning would go a long way toward improving performance overall... and reducing the length of the application development lifecycle.
Programming performance-oriented SQL into your programs from the beginning would go a long way toward improving performance overall... and reducing the length of the application development lifecycle.
7.Using NULLs Can Save Space
8.RUNSTATS Aren’t That Important
If you don't work with up-to-date RUNSTATS then you are hobbling the DB2 Optimizer and almost assuredly getting sub-optimal access paths for your DB2 SQL.
9.DB2 is a Hog
If you don't use it properly, every piece of software can become a resource hog. If you acquire the knowledge on how to work properly with DB2 then it will hum along like a well-oiled machine!
10.It Depends!
This is the answer that can be used for every DB2 question. But if that answer is not followed up with what "it" depends upon, then it is a useless answer... and whoever gave you that answer is probably just trying to get rid of you instead of helping you with your problems.
This is the answer that can be used for every DB2 question. But if that answer is not followed up with what "it" depends upon, then it is a useless answer... and whoever gave you that answer is probably just trying to get rid of you instead of helping you with your problems.
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