| Team Fly | |
NOTE
In order to work with the code snippets and the sample schemas we discuss throughout this book, you will need to have the Oracle Database 10g software installed and the first database successfully created. The Database Configuration Assistant (dbca) is the fastest way to set up your first database. Most of the time you simply accept the defaults suggested on the dbca screens. If you have any problems with either the software installation or the dbca, please consult either a more senior colleague or surf MetaLink (http://metalink.oracle.com) to get assistance, after supplying appropriate login credentials.
These are binary files containing information about the assortment of files that come together to support the Oracle Database 10g. They contain information that describes the names, locations, and sizes of the database files. Oracle insists there is one control file, but savvy technicians have two or three and sometimes more. As the Oracle Database 10g is started, the control files are read and the files described therein are opened to support the running database.
As sessions interact with the Oracle Database 10g, the details of their activities are recorded in the online redo logs. Many think of these as the transaction logs. A transaction is a unit of work, passed to the database for processing. The following shows a few activities that can be referred to as two transactions.
-- Begin of transaction #1 create some new information update some existing information create some more new information delete some information save all the work that has been accomplished -- End of transaction #1 -- Begin transaction #2 update some information back out the update by not saving the changed data -- End transaction #2
Oracle Database 10g insists that there are at least two online redo logs to support the instance. In fact, most databases have two or more redo log groups with each group having the same number of equally sized members.
| Team Fly | |