Many times I am asked how to tailor the initialization parameters for a specific process or user. Essentially the easiest way to set custom initialization parameters for a particular session is to use the ALTER SESSION SET command in a logon trigger keyed to a specific schema or schemas. For example, say we had an application where we wanted to set ...

In old version of Oracle database, it is easy to control the join path by reordering the tables in table list after the FROM clause, but it is getting difficult to control the join path in today’s cost based SQL optimizer, I am going to introduce method that is applicable in most databases such as Oracle, Sybase, DB2 and SQL Server in the following:

To control a join path, we cannot tell the database SQL optimizer which path is the best one to select. Instead, we add something to the syntax of the SQL statement that causes an increase to the cost of the current join path selected by database SQL optimizer. Let’s take a look at the following example of two table join scenarios.

Last month I wrote about “Why Reverse Engineering is Always Worthwhile.” So the logical next issue to examine is forward engineering – its different approaches and its many comparative benefits. The best way to do this is via an analogical example

Oracle’s Oracle10g requires more memory than was ever required before. If you utilize any of the new features such as automatic storage management (ASM) and automatic shared memory management (ASMM) then you really need to pay attention to what memory is doing in 10g.

When an exception is raised, one of the most important pieces of information a programmer would love to get hold of is the line of code that caused the exception to be raised.  Before Oracle 10g came long, the only way to get this information was to allow the exception to go unhandled and then view the error stack. The following chain of program calls shows you what I mean.